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ODEON Room Acoustics Program

1. 2 38 Copenhagen Central Station Array par is available in the Auditorium and Combined editions of ODEON This example demonstrates the newly installed PA system which utilizes 20 beam steered line arrays Several measured parameters are available including STI 2 39 3 Modelling Rooms Creating new room models is probably the most time consuming task in room acoustical modelling However good modelling practice will greatly reduce the time used for modelling and re modelling rooms In order to study a room in ODEON a file containing the description of the room s geometry will have to be created All subsequent derivative files and result files are created and managed by ODEON The file containing the room model must be written as an ASCII text file having the file extension Par the old ODEON Sur file format is also allowed though not described in this manual You can choose to create the geometry file either by typing the model data directly into a text file in the supplied text editor opeoneEdit using the format described in Appendix E using Google SketchUp the ODEON Extrusion Modeler described in section 3 2 or a third party CAD program e g IntelliCAD Autodesk Revit AutoCAD 3DStudioMax MicroStation OF Rhino which is capable of creating 3D surface models and exporting these as dxf files as described in section 3 3 Finally you may combine the different modelling methods import a CAD model from a CAD pro
2. NumbOffSet 2000 MReset restoring default origo CoordSys X Y Z restoring default coordinate system More model data HHH Hl Using the 3DOpenGL display for model verification This display is very useful for detecting holes in the geometries Especially if stepping outside the model Arrow back shortcut and rotating the model using the ctri arrow shortcut See the corresponding 3D0penGL dropdown menu for more shortcuts When materials have not been assigned to all surfaces in the room surfaces will appear in random colours making holes easier to spot If materials have been assigned the colours will by default reflect the acoustic properties of the surfaces however it is possible to turn on the random colouring at will using the r shortcut If the model contains layers it is also possible to show the layer colours using the ctri L shortcut Do note That 3D0penGL may occasionally fail to display complicated surfaces including numerous holes correctly typically surfaces created by CAD software using solid modelling techniques and subtractions although the surfaces are perfectly legal with respect to ODEON In these rare cases you may assure yourself that the model is in fact correct by putting point sources at various test positions and conduct tests using the 3D Investigate Rays and 3D Billiard utilities a 3DGeometry debugger Overlapping and warped surfaces should be avoided in the room model specified in the geometry fil
3. sesesssssserensnrrrnrnrerrrrrenne 1 14 1 3 How to upgrade or update your current license sssssesensrrnrererenrrrnrnrsnrnrrrnrnnne 1 15 Remote License Update or Upgrade is divided into four stepS s sssssssrerensrrrrererenrns 1 15 2 SHO Me OUNCE TOUT S aq xeae uae ene sae eagaaxeme mnateae eau A aoe say A A E senaraak 2 17 2 1 Short guided tour Combined and Auditorium editions ccc cc ccecceeeee eee e eee eens 2 18 Summary of the calculation Methods cccceeeeeee eee eeesseeeeenennnnnneeeeeeeeseeeeagneannannees 2 26 2 2 Short guided tour Industrial CGIUION ciscacesavciavesniaakvesssaevesaracevaneracsvesernsexeanvast 2 30 2 3 Short guided tour Basics edition cc cccccceeeeeeeteeeeeenennneneeeeeeeeneeeeeeguennaannees 2 34 2 4 Pre calculated ROOMS Round RODINS ccc cccccccccceeee eee e eee eee e eens eeeeeeeeeeeeeeeeennees 2 37 3 Modeling ROO aarne a E E E EE saa aauyaquranuiese eaareeyyaneraas anes 3 40 3 1 Guidelines on room modelling sssssssssssssnssssnsnsnnssronesrnnsunnnesnnnrsnsnsnnsnrenenrnne 3 40 Default coordinate system sssssssssrsrrsrrnrsrrnnrrrnnrnrrrenrrrrnnrrrnnrnrnnrnrsnenrrnrnrrrrnnrreno 3 40 Recommended size of a SULFACE cccccccccccccccccceeceeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeees 3 40 cUe SUI CSS aa A aoptarteamnenen Soptatsearnctota pase teane pon Swonceebsee canara eawganburasbe 3 41 What to modal sciccastaniacseaaedagsiasssevadvateset
4. w te i __ Figure 11 5 Same as fig 11 4 but with a time delay 0 2 ms per unit At the 2 kHz band and higher frequencies i e above the upper limiting frequency 1720 Hz in this example a rather strong side lobe of radiation is seen at various directions slightly 11 109 upwards This is the effect of the units being more than one wavelength apart from each other If the phase is shifted by one period another angle of radiation is found Geometrically the angles that correspond to periods phase shift can be calculated from pix arag MAIL where f is the frequency and 1 2 etc The theoretical angles of radiation corresponding to this example are shown as a function of the frequency in Table 11 2 below The direction of the main lobe relative to the horizontal direction is 10 for At 0 1 ms and 19 At 0 2 ms The results for 1 explain the upward side lobes seen at 2 and 4 kHz in fig 11 4 and 11 5 Table 11 2 Calculated angles of radiation from the example array with d 0 20 m Positive angles are downwards and negative angles are upwards Calculated for two different values of the delay per unit At 19 19 19 19 19 19 19 Delay for transducers in an array should not be confused with delays assigned to the overall delay assigned to a point source or array source in order to benefit from the HAAS effect although the devices used in order to obtain the delays may be identical e Del
5. Examples A few examples on extrusion models are installed with ODEON the examples are located in the ODEON rooms oes Directory The best way to learn about benefits as well as limitations of the extrusion modeler may be to load the examples investigate the surfaces e g scrolling the point and surface tables and to load the models into ODEON in order to investigate the models when they become extruded Special extrusions There are a few extrusion surfaces which are treated differently by the extrusion modeler 1 A surface with an extrusion height of zero will produce one and only one horizontal surface no matter if a bottom or top surface is selected 2 An extrusion surface which only contains two points will only produce one vertical surface neither bottom or top surface is produced only a single extruded surface if the extrusion height of this surface is zero then no surface is produced an exception to the exception 3 50 3 3 Importing DXF and 3DS files If using models from AutocaD it may be an advantage to use the 3ds file format for export from AutocAD and Import into ODEON rather than the dxf format This procedure will ensure that all relevant data from the CAD drawing are exported in a way which can be used directly by ODEON For AutoCAD versions older than 2007 exporting in the 3ds format can be done using the 3DSOUT command For AutoCAD 2007 and later versions this 3DS Utility is available at
6. The levels presented in auralisation samples created by ODEON are influenced by e The HRTF s e Level in input signal file e g the RMS value or Lega e Calculated Sound Pressure Level which is based on geometry sources receiver positions materials etc Overall recording level iN the Auralisation setup Rcd Lev iN the Auralisation display of the JobList if off line convolution is used Mixer levels mix Lev in the JobList if off line convolution is used Gain iN the Streaming convolution dialog if the real time convolution option is used Output gain of the soundcard the volume setting Sensitivity of the headphones Coupling between headphone and the subjects ear Maximised play back levels for maximum dynamic range If you are only interested in the best sound quality in your auralisation files you may focus on getting an Output Level out Lev in the auralisation display within the Job list below but as close to O dB as possible in the convolve BRIR and Signal file table and in the mix convolved wave results into one wave fle table in order to obtain the highest dynamic range If using the streaming convolution Option available from the main display in the Joblist ODEON will maximize the auralisation output level 5 68 if changing input signal or BRIR from within this display you may press the Maximize Gain button to maximize the gain for the new setup Relative play back levels In some cases you ll be interested in obt
7. metes RAR l 10 00 Odeon 1985 2009 Licensed to Odeon A S metes Rahe l 10 00 Odeon 1985 2009 Licensed to Odeon A S 10 00 metres front Figur E5 The Quadropol sample viewed in the Near filed balloon tab tn the Array source editor To the left at 63 Hz to the right at 4 kHz Testing if XML files can be imported correctly into ODEON The demo version of ODEON or a full version of ODEON Auditorium or Combined can be used for this purpose If you are reading this you have probably already installed it if this is not the case you may download the demo version from www Odeon dk To model and view the array in ODEON you only need to use a very limited number of features there is no need knowing all features in the ODEON software In a full version you may import your array into any room In the demo version you should open the ArraySpeakerTestRoom Par room located in the AppendixD folder e g C ODEON11Combined Rooms AppendixD ArraySpeakerTestRoom Par The ArraySpeakerTestRoom par room is a large box measuring 100x100x20 metres by default all surfaces have been assigned 100 absorbing material as its not intended for room acoustics predictions To load this room use the FileJOpen Room Menu entry Once loaded open the Source receiver list Shortcut Shift ctri S In the Source receiver list define an array shortcut a In the Array source editor import a XML array file Shortcut ctri o That s it Hopefully the a
8. ODEON ROOM ACOUSTICS SOFTWARE Version 12 User manual Basics Industrial Auditorium and Combined Editions Odeon Room Acoustics SOFTWARE Auditorium Acoustics Sound reinforcement Noise Control Front Figure Front picture from room model of theatre Acoustic consultant COWI A S 1 1 ODEON Room Acoustics Software Version 12 2 Edition Basics Industrial Auditorium and Combined Editions by Claus Lynge Christensen amp Georgios Koutsouris Odeon A S Scion DTU Diplomvej building 381 DK 2800 Kgs Lyngby Denmark www odeon dk 2013 1 2 1 3 Introduction This manual is intended to serve as an introduction on modelling room geometries in ODEON software on the facilities for measurement and simulations and the applied calculation principles behind It will not cover in depth all facilities included in the ODEON software explanations of displays calculation parameters results etc are available as context sensitive help from within the ODEON applications shortcut Fi It is recommended to use the online help to learn about the specific features available from the different displays the interpretation of results calculation parameters etc The contents of this manual are as follows Chapter 1 covers installation of the program changes from previous versions etc Chapter 2 is a short guided tour introducing the ODEON program and its facilities including specification of calculation parameters definitio
9. sssssssrssrsrrnrrrenrsrrnn 9 100 10 Directivity patterns for point SOUrCeS sssssssssrsnrsrrnrsnrnnsnrerrnrrnrnrsrrnnrrrnnenenns 10 101 10 1 GeNErie POINT SOUCO S pererin E E EE E E EEEO 10 101 102 Naural PONE SOU COS cornine Er E E Ea E EA A 10 101 10 3 Common loudspeaker format CF1 and CF2 file S ccccccceseeeeeeeeeeeeeeeeeeeeeees 10 102 10 4 Creating new directivity patterns in the ODEON S08 forMat s sssssserersrsrrens 10 102 11 EIN arn ay SOUNCC Siacarncarmeuruounanvanterobtandeneteatonouvaed teen vaaieceuread maurnoe E E E 11 107 eE Se IG VS CIES aapraceasxctse scsssamcten E E E A iene 11 107 11 2 Playing with delay wasawiuactanowsresoanenccaees sunntineeeneaessusaossananeacerasees earauanesananaee 11 109 Pies Payna wW EVO aa a E A E EE E EA AAA 11 110 11 4 Combining delay and level adjustments sosnssssnnnssrnnsnrnnrnrerenrrrrnrsrrnrsrrnn 11 111 11 5 USING the equalizer sssssssssssssssnssssnsssnnssssnssnsnennsnennessensssnnesnsnrsnsnennenenne 11 111 11 6 Bringing the array into the room sssssssssssssssnssssnsssnnsssnnsssnnssnsnssnsnesnssenne 11 111 12 Measurement SY Stens AA knertasete tad 12 113 12 1 Introduction Method cissiciccscsccccctisvecassivceasssieccesstnntisnsanedesnseesteinedensaaaeenses 12 113 12 2 Measurements and Processing sssssssssssssnssnsnssnsssnnessnnessnnesnenesnsnennenenne 12 114 Measure Impulse ReSponSe sssssssssssenssnsnesnsnrsnsnrnnsnrenenrnneunnnesn
10. 2 13 000 ElevSurf2 I 1 22 2 7 TB walls HHH Defining a number of surfaces using the CountSurf statement The CountSurf is mostly here for backwards compatibility In most cases it will be easier to use the Surf statement along with a for end loop A Counter surface is divided on two lines and must follow the syntax CountSurf lt First Surface Number gt lt NumberOfSurfaces gt lt Optional name gt lt ListOfPointNumbers gt lt FirstSurfaceNumber gt A unique number from 1 to 2 147 483647 for identification of the surface Using the same number but with negative sign defines the surface and its counterpart mirrored in the XZ plane Y O A CountSurf will take up several surfaces numbers which must all be unique lt NumberOfSurfaces gt The number of surfaces to be created by the CountSurf call lt Optional name gt Optional user defined name for easy identification of the surface e g Beam lt ListOfPointNumbers gt Each surface may be bounded by between 3 and 50 corners which all lie in a plane Corner numbers refer to the corners which must have been defined e g using the Pt or CountPt statement before using the surface statement The order of listing must be as obtained by travelling around the surface s edge in either direction The list of corners must be on the same line A room may contain up to 10000 surfaces Example CountSurf 1000 5 Beam in ceiling 1000 1100 1200 1300 will produce five su
11. E Global Estimate This method estimates the global reverberation times T T3 using the method proposed by Schroder Schroeder 1970 as well as mean free path and generates estimates of decay curves Particles are sent out in random directions from the source see section 6 7 and reflected using the Vector based scattering method see section 0 ODEON records the loss of energy in each particle as a function of time occurring because of absorption at room Surfaces and in the air Summing over many particles a global energy decay function for the room is obtained The decay curve is corrected for energy which is lost due to the truncation of the decay curve This is analogous to an ordinary decay curve except there is no specific receiver The summation process may be carried on for as many rays as desired Evaluating results When the decay curve seems smooth derive the results It is often the case that To values are longer than To values If T3 7 values are shorter than To it is likely that the number of rays used were too small in that case press the Recalculate button If the reverberation times are _ the Impulse response length defined at the Room Setup page is too short to derive the reverberation parameter 6 3 Calculation of Response from Sources to Receivers This section describes the methods used to predict the response from a source to a receiver This is the process used to in order to predict Single Point M
12. E Measured JV ceeeeeees Estimated end of response 0 0 1 0 2 0 3 0 4 0 5 0 6 0 7 0 8 0 9 1 1 1 1 2 1 3 time seconds Odeon 1985 2011 Licensed to Odeon A S Fig 12 7 An example of impulse response where the magnetic feedback from the recording system is very dominant The feedback produces a sharp pulse before the actual start time of the impulse response This pulse is wrongly detected as the start time of the impulse response and the estimated end is wrongly placed before the actual direct sound 12 123 C Odeon12Combined Measurements IR_Basement_Long wav Raw decay curve broad band M E Measured jv Noise floor Onset time Truncation time SPL dB 0 0 1 0 2 0 3 0 4 0 5 0 6 0 7 0 8 0 9 1 T i 1 2 1 3 Odeon 1985 2011 Licensed to Odeon A S HINe Seconds Fig 12 8 Same impulse response as in Fig 12 7 Now the Noise floor window length is set to 60ms With this adjustment the estimated end of the response is placed correctly and a truncation time is derived However the onset time is still misplaced due to the magnetic feedback C Odeon12Combined Measurements IR_Basement_Long_Cropped wav Raw decay curve broad band fv E Measured Noise floor Onset time Truncation time a rei ee ceca ecrereceerreerrrr ierecereerRrRerecereeceets Peres COREE E CEC CE CEE LEEPER TESCO EEE CLEC CCC CECE N CEST ETE OCLC CDSE EEE ECR Peace CecRErerrerr ee torneo on eee ere eee ee peer e
13. From within the Materials list run the Quick Estimate to get an idea of the reverberation time Note the longest reverberation time This calculation is very useful while assigning materials for evaluating different materials and their impact on the reverberation time Before leaving the Quick Estimate YOU may want to try this out by choosing different materials It is possible to select among the defined sources However the source position will only have minimal effect on the global estimated reverberation time unless strong coupling effects are present in the room Et Room setup calculation parameters At this point you should have an idea of the order of size of the reverberation time To continue the series of calculations you should enter the Room setup and specify the impulse response length The Impulse response length Should cover at least 2 3 of the decay curve in this case 2000 ms Should be sufficient To learn more about the other parameters available from this page use the Fi shortcut calculating point responses At this point we are ready to calculate point responses One type of point response calculation is available in the Basics edition e Multi Point Offering room acoustical parameters for all the receivers defined in the Receiver List at the Source Receiver List Setup a Multi point response and run it e Activate source 1 in job one source 2 in job two source 3 in job three and all three sources in job four e T
14. Hints The order in which the coordinate manipulations are carried out is important usually but not necessarily always the MScale commands should come first then the MRotate commands and finally the MTranslate commands If you are not familiar with coordinate manipulations it may be a good exercise to try different manipulations on the sample geometry above and load the geometry into ODEON upon each change Using layers in ODEON The Layer statement allows dividing geometry into separate parts which can be displayed separately and in its own layer colour in the 3pDview 3DOpenGL and Materials list This makes it easier to model and investigate selected groups of surfaces When importing geometry from a dxf file e g from AutoCAD where layers are an integrated part the layers included in that file will be preserved in the imported version of the room If layers have been used in geometry the layer can be activated or deactivated in the 3pview 3DOpenGL and Materials list The layers menu is activated from these windows using the Ctri L shortcut Vocabulary what s a layer Layers are commonly used in CAD modelling programs such as autocad in order to make complicated geometries manageable Layers in CAD programs and some drawing and picture editing programs can be compared to overhead sheets without any thickness You define a number of layers with different names and possibly different line colour thickness etc and
15. Rindel J H amp Christensen C L 2008 Modelling Airborne Sound Transmission between Coupled Rooms Proceedings of BNAM 2008 17 19 August Reykjavik Iceland Rindel J H Nielsen G B amp Christensen C L 2009 Diffraction around corners and over wide barriers in room acoustic simulations Proceedings of the 16th International Congress of Sound and Vibration 5 9 July Krakow Poland 12 129 Rindel J H Nielsen G B amp Christensen C L 2009 Multi source auralisation of soundscapes in large buildings Proceedings of Euronoise 2009 26 28 October Edinburgh Scotland Schroeder M R 1970 Digital Simulation of Sound Transmission in Reverberant Spaces J Acoust Soc Am 47 424 431 Stroem S 1979 Romakustisk prosjektering in Norwegian Anvisning 20 Oslo Norges Byggforsknings institutt Vigeant M C Wang L M Rindel J H Christensen C L amp Gade A C 2010 Multi Channel Orchestral Anechoic Recordings for Auralizations Proceedings of ISRA 2010 29 31 August Melbourne Australia Zang M Tan K C amp Er M H 1998 Three Dimensional Sound Synthesis Based on Head Related Transfer Functions Journal of Audio Engineering Society vol 46 10 836 844 12 130 Appendix B Vocabulary The techniques of auralisation make use of many of technologies and a lot of technical terms and abbreviates are commonly used in the literature Here is a short vocabulary to some of
16. Sub Each Octave band has the centre frequency fe defined according to ISO 31 5 63 125 250 500 1000 4000 8000 and 16000 Hz For each of the octaves there are Ns number of Sub bands nodes of the Sub type the center frequency of the sub bands are defined from the following algorithms The frequency f of the lowest sub band in an octave is defined as follows 1 E And the following frequencies f sub bands are defined as 1 Ja Ta Where n 2 to n The 6 sub bands Ns 6 centered around 1000 Hz have the following centre frequencies a7 49 153538438340749 _ _ 1059 46309435929526 1189 20711500272106 1334 83985417003436 Frequency of n sub band in 1000 Hz octave for N 6 Results of calculations should be for full octave bands for the octave bands 63 125 8000 Hz ISO suggests that center sub octave frequencies should be derived from 1000 Hz For an uneven number of bands e g 1 3 octave bands this gives us one band below one band at and one band above the center frequency of the Octave center frequency so the 3 sub octaves are in balance relative to the octave band however for an even number of sub band frequencies thing becomes unbalanced if using ISO frequencies there will be 2 sub bands below and 3 sub bands above the full octave band centre frequency or opposite 3 below 2 above Attributes Re Img The energy of the transducer is emitted in N Sub nodes The center frequencies
17. 2 20 Fed Define a receiver grid and calculate grid response Enter the Define Grid menu and select the two floor surfaces surface 1001 and surface 1002 Specify the Distance between receivers tO 2 metres then click the Show grid button Close the Define Grid dialog to save the grid definition The auto grid detection will automatically find the surfaced from which a elevated grid can be reached with direct sound from the defined source Note If the Define Gria button is disabled this is because some process is open which requires data to be saved In this case it is probably the Estimate Reverberation display that needs to be closed To find this open window use the windows menu item on the menu bar Other displays containing calculation processes may cause the same kind of disabling of miscellaneous options Hint The grid may also be used for easy positioning the point sources and discrete receivers which are usually defined in the Source receiver list TO learn how to operate the 3DGrid display select the display and the 3pcrid tab in that window then select the 3DGrid Parameters dropdown menu Calculate grids Click the Job list button again Activate the Gria option from the joblist by checking the Grid option for job 1 then click the Run all OF Run Selected Job Dutton ODEON will now start calculating the Grid response for this job this may take a while When the calculations is finished select job number 1 in the Job
18. For every impulse response the correct onset time is indicated in the display According to the ISO 3382 Standard ISO 3382 1 2008 the onset of the direct sound and of the whole impulse response should be counted 20 dB below the peak of the direct sound This dB value is called Trigger level IN many cases a lower value for the Trigger level may be needed and this is the reason why this is an adjustable parameter in the ODEON measuring system 12 2 Measurements and Processing Important settings Before starting a measurement make sure that your equipment and settings fulfils the following prerequisites SNR of sound card and microphone The sound equipment you use for the measurements sound card microphone and amplifier Should provide a decent S N otherwise you will need long measurement times in order to Suppress background noise caused by the equipment In principle the longer is the sweep Signal the higher is the suppression of the background noise Analog filters of sound cards Some cheap sound cards may have very poor realisation filter which should cut off high frequencies above the Schroder s limit If this is the case you will notice that the sweep reproduced over the loudspeaker does not appear to be going monotonically from low to high frequencies If pronounced it is recommended to use a better e g external sound card Setting microphone amplification If using the built in microphone amplifier it has a mixer slider
19. Sheet Z Sheet3 Ki H Ready Sum 825 y Figure D1 Copying material data of the reduction index from MsExcel A material to be copied may contain a leading comment name and must end by 24 floating point values denoting the 24 reduction indexes from 50 Hz to 10000 Hz the first value is always assumed to be for the 50 Hertz one third octave band if the number of bands is less than 24 then the last value is used for the bands above if more than 24 values the values above 10 kHz are discarded To copy the values from MsExcel mark the relevant cells and press Ctri C to paste the values into Transmission dialog simply press Ctri V Likewise to copy data from the Transmission dialog to MsExcel press Ctri C while the dialog is the selected window in ODEON then select the first cell in MsExcel or which ever cell is relevant and press Ctrl V Data can also be imported from Insul Sound Insulation Prediction software Insul simply by Copy the spectrum for Bastian format and paste into ODEON A wall with different material on either side and walls modeled with thickness Sometimes a transmission wall may be composed by two individual surfaces two separate surfaces in the MaterialsList aS Shown in the illustration from the 3pBilliard display below It is possible for ODEON to link together such a pair of surfaces if they are almost parallel allowing transmission trough walls with different absorption properties on either side The reduc
20. Sweep and the expected Impulse Response length which defines the final length of the recorded impulse response as well as the extra recording time after the end of the sweep It is recommended to make an initial measurement Sweep length s000 ms Impulse response length 1000 ms Bey Play test signal he Measure Gain a dB Ado input Stereami eakek High Defi with the default values and check the quality of udio input Stereomi Realtek High Definit n e eA te red aeh with selected audio devices no calibration applied t h e O bta n ed m p u Se res p O n Se b efo re C h a n g n g Status Idle doing nothing in particular them You can pre listen the sweep signal by pressing the Play test signal button The level of the sweep signal can be adjusted from within ODEON using the vertical Gain slider Specific values can be also entered at the Gain box On the right most side of the window two indications for the output level are displayed The blue bar shows the current level captured by the microphone while the red bar shows the maximum peak value being captured so far You can pre listen the sweep signal by pressing the Play test signal button A measurement can be initiated by pressing the measure button The status of the measurement is displayed at the bottom of the window When the sweep signal has been played the extra decay period is recorded afterwards keep as quiet as possible during the peri
21. The number of surfaces to be created by the ElevSurf2 statement If creating a cylinder a number between 16 and 24 is suggested if it s a column only use six to eight surfaces lt Height gt Height is oriented in the Z direction lt T B N gt The 7 B N parameter specifies whether the E levSurf2 should have a top and or a bottom The options are T B TB and N for none If Top or bottom may only be included if all of the points in the floor in the elevation surface are in the same plane Example on use of the MPt and ElevSurf2 statements First the perimeter points point 1 to 23 at the floor level of an office environment is described using the MPt statement Then the elevation surface is created from these points creating the perimeter walls of the office with a constant height of 2 7 metres In this example the X coordinates are made in absolute values whereas the Y coordinates in most cases are in or de creased using the or options To create a closed E evSurf2 that is the first wall joins the last wall first and last point in the series of points handled to the ElevSurf2 must be identical in this example point 1 and point 23 are identical If an elevation surface has 22 surfaces then 23 points must be made available to the FlevSurf2 as in this example HHH MPt I 23 000 12 153 49 62 2 02 48 22 1 1 45 3 2 68 43 85 1 45 42 40 40 98 1 45 0 34 5 2 1 30 13
22. can be useful when creating and verifying geometries for ODEON 4 3D View Interior Exterior mode y Ni Corner closest to mouse pointer 1301 x y z 0 000 6 500 137 700 8009 ceiling part 5 8010 CEILING PART 6 7 Mf 6 X y ag N 4 X i y N A A y d Y u Y r i ol Ds Corners in surface no 8010 409 xyz 26 100 14 300 139 700 56 xyz 29 700 15 000 139 700 55 xyz 30 300 12 800 139 700 42 xyz 37 100 14 600 139 700 44 xyz 37 300 12 850 139 700 46 xy z 37 100 12 650 139 700 37 300 6 650 139 700 37 100 6 650 139 700 37 400 0 000 1 39 700 37 100 6 650 139 700 37 300 6 650 139 700 50 xyz 52 xy z 150 xy z 148 xy z 146 xyz 37 100 12 850 139 700 144 xyz 37 300 12 850 139 700 xy 155 xyz 156 xy z 6409 xy z 30 300 1 2 800 139 700 29 700 15 000 139 700 26 100 14 300 139 700 Figure 1 Viewing corners and coordinates in a selected surface using the N shortcut and highlighting corner and displaying the coordinates of the corner closest to the mouse pointer using the M shortcut The perspective option shortcut Pp allows you to turn off the perspective of the room to get an isometric display of the room This may prove valuable when investigating warped Surfaces xl The unique Edges Option in the 3pview display shows edges which only occur on one surface Such an edge is
23. draw the different parts of your geometry on the different layers The layers can be turned on or off in the CAD program allowing better overview by hiding parts of the geometry that are not relevant in a part of the drawing process Syntax for the Layer statement Layer lt Layer name in quotes gt lt R intensity gt lt G intensity gt lt B intensity gt or as another option Layer lt Layer name in quotes gt lt LayerColour gt lt Layer name in quotes gt A descriptional name which must start and end with a quote sign lt R intensity gt lt G intensity gt lt B intensity gt Three floating point values between O and 1 which together is describing the colour of the layer as a Red Green Blue intensity If using the Layer command sShift ctri L from within the ODEON editor the colour intensities are set by clicking the desired colour in a dialog box Do note that it s not advisable to choose a greyish colour as it may not be visible in ODEON lt LayerColour gt As another option the colour of the layer can be described using one of the predefined colours Black Blue Cream Fuchsia Gray Green Lime Maroon Navy Olive Purple SkyBlue Teal MoneyGreen or White The LayerColours par eXample demonstrates the different colours The LayerStatement par example shows how to create a geometry on three different layers Selected surfaces can be selected for display in the 3pview 3D0pencL and the Materials list 1
24. free it might be the edge of a free hanging reflector but it also could be the result of an error whereby two surfaces which Should join along an edge do not Example Modelling a box shaped room consisting of 6 surfaces but forgetting to define the 6 surface in the geometry file This room will have a hole where the 6 surface is missing The unique edge s option will show where the missing surface should have been 3 56 3 5 Combining geometries It is possible to combine geometries imported from an external CAD program with geometry modelled in the Extrusion modeller or modelled in the parametric modelling format of ODEON A geometry imported from a CAD program or generated in the Extrusion modeller is always in the par format and as such they may be combined in the ODEON Editor When combining different geometries from different sources some facilities in the parametric modelling format may be quite useful NumbOffset CoordSys Unit MTranslate MRotateX MRotateY MRotateZ MScale MReset and MPop Below is an example outline which illustrates how a number of geometries can be merged together into one parametric file HHH CoordSys X Y Z Jai 1 model data ne 1 model data NumbOffset 1000 _ avoid reusing point and surface numbers which have already been used CoordSys Y X Z swap coordinate axes if needed MTranslate 01520 Translate move geometries as needed tele 2 model data san 2 model data
25. it is not too difficult to keep track of things but for realistically complex rooms a systematic approach is desirable You will typically have a set of drawings which have to be used as the basis for the ODEON model It pays to spend quite a long time working out how the room can be simplified to a manageable number of sensibly shaped plane Surfaces sketching over the drawings These ideas will have to be modified when you start to work out the actual coordinates to ensure that the surfaces really are plane Here are some ideas that may help you to create correct surface files faster e Exploit symmetry If the room has an axis of symmetry place the coordinate axis on it Then use the sign convention for symmetric semi symmetric modelling e If there are vertical walls and or features which repeat vertically e g identical balconies use the CountPt CountSurf RevSurf statements or indeed For End constructs e Build the room gradually testing the Par file at each stage of growth by loading it into ODEON and have a look at the result e Use hybrid statements such as Box Cylinder etc Where it is difficult to get surfaces to meet properly without either warping or using lots of Small surfaces to fill the gaps allow the surfaces to cut through each other a little This will usually ensure a watertight result and has only minor drawbacks These are i the apparent Surface area will be a little too big affecting reverberation time
26. random direction due to the Lambert distribution If the Scattering method is Set tO None s 0 scattering is not taken into account thus all reflections are calculated as specular If the surface scattering is set to Full scatter s 1 all surfaces will scatter 100 The Full and None scattering methods ARE NOT RECOMMENDED except for educational or research purposes Oblique Lambert The Oblique Lambert Method allows frequency dependent scattering to be included in late reflections of point response calculations this option is recommended Reflection Based scatter The Reflection based scattering Method automatically takes into account scattering occurring due to geometrical properties such as surface size path lengths and angle of incidence The use of the method is recommended unless that part of scattering has already been included in the scattering coefficients assigned to the room s surfaces Interior margin Typical geometrical offsets in the boundary of the room default is 10 centimetres Surfaces which are closer to the boundary surfaces of the room than the distance specified by the interior margin will also be considered boundary surfaces this means that surfaces such as doors and windows which may be modelled as being slightly on the inside of the boundary walls will still be considered as boundary surfaces Interior Surfaces are displayed in a green colour teal in the 3pview whereas boundary surfaces are black so a change
27. the full 90 vertical angle In most cases the Dome2 statement is probably better suited The syntax for Dome iS Dome lt Number gt lt NumberOfSurfaces gt lt Radius gt lt RevAngle gt lt optional name gt lt Number gt A unique number from 1 to 2 147 483647 for identification of the first point and surface in the Dome Using the same number but with negative sign defines the dome and its mirrored counterpart in the XZ plane Y 0 A Dome will take up several point and surface numbers which must all be unique lt Radius gt Radius of the Dome must always be greater than zero lt Revangle gt Revangle must be within the range 360 and different from zero If RevAngle is 180 a half Dome is generated if its 360 a full Dome is generated Positive revolution angles are defined counter clockwise Connection points 12 164 The right side vertical points in Dome are stored in PlistA The left side vertical points in Dome are stored in PlistB In the special case where the revolution angle is 180 all points are stored in PlistA and the number of vertical subdivisions is stored in ONVert The example shown was generated with the following code HHH const N 16 const R 15 Dome 1 N R 270 This is a dome HHH Hint The dome can be made elliptical using the MScale statement The Dome2 statement vertical revolution angle is not necessary 90 Rather then specifying the dome by a revolution angle it is spec
28. the most used expressions the vocabulary is not a complete description of the individual words the context under which the words are used are many and the subjects are rather complex Anechoic recording Anechoic recordings are recordings of sound sources made without any reflections from the Surroundings contributing to the recordings A common problem with anechoic recordings are that they may often include to many high frequency components because they are usually near field recordings and because they are recorded on axis where these components usually dominate When using such recordings with auralisation systems this may often result in unrealistic sharp s sounds especially in case of long reverberation times Anechoic recordings are usually recorded in an anechoic room but semi anechoic recordings may also be acceptable for use with auralisation systems this could be out door recordings of machinery trains etc or studio recordings of music Auralisation auralization The term auralisation was invented by Mendel Kleiner who gives the following definition Auralisation is the process of rendering audible by physical or mathematical modelling the sound field of a source in a space in such a way as to simulate the binaural listening experience at a given position in the modelled space When used in ODEON one may think of auralisation as the art of creating digital simulations of binaural recordings in rooms which may not be b
29. user defined Transition order It is not given that more is better Number of early scatter rays Job calculations only If the specified Number of early scatter rays iS greater than O the early reflections from point sources are split into a specular part an image source and a scattered part given by the scattering coefficients 100 scatter rays per image source should be sufficient The scatter rays are traced from the reflection order of the images source up to the selected Transition order Select calculation methods Angular absorption Job calculations and Global Estimate When this option is on angle dependent reflection factors are taken into account The calculation method uses the diffuse field absorption coefficients as input but generate angle dependent ones taking into account angle of incidence and the size of the surface The method is based on the work in Rindel 1993 In some situations this option does not improve the results but on the other hand it does not seem to harm but in many situations it means a significant improvement Three options are available Disabled All materials ANC Soft materials Only The All materials is the thorough method whereas the Soft materials Only is a trade off between calculation time versus prediction quality The soft materials ONly method is usually almost as fast as the Disabled option and yields a quality almost as good as the All Materials method which is somewhat slower Screen di
30. 1994 which are installed but do need to be imported or Subject_021Resi0deg Algazi 2001 which are installed as well as imported you should create a text file following the same format as used in the files Unity ascii_hrtf Kemar ascii_hrtf and Subject_021Resi0deg ascii_hrtf These files can be found in the HeadAndPhone EE and HeadAndPhone Ec directories To import a set of HRTF s select the Tools Create filtered HRTF s option then select the specific HRTF ASCII file e g C ODEON HeadAndPhones EE Kemar ascii_hrtf finally specify miscellaneous parameters when the import dialog appears for help on these parameters please press Fi from within that dialog You may also desire to import a set of HRTF which has already been imported in order to specify an alternative filtering approach e g to enhance the HRTF s in different ways Headphone filters It is possible to compensate for non linear frequency response of headphones When a headphone is selected ODEON will filter the output through a minimum phase filter with a 5 67 frequency response inverse to that of the headphone A number of headphone filters are supplied with ODEON in ODEON s hph format Filters ending on ee hph are measured on a dummy head at the entrance of a blocked ear canal whereas filters ending on ec hph are measured at the end of the ear canal at the ear drum so to speak The selected headphone filter should match the HRTF used for example the subject_02
31. 344 m s is the speed of sound However the concentration into a single beam only works at frequencies below the upper limiting frequency i e when the distance between the units is short compared to one wavelength C lt Above f the sound radiation breaks up into a number of directions In fig 11 1 is shown the near field radiation at 1 kHz with different number of units in the array from 1 to 11 The unit in the example is SLS_LS8800 CF2 imported from the CLF collection of loudspeakers and the distance between units is d 0 20 m Whereas the single loudspeaker unit spreads the sound in a wide fan the level decreases rapidly with distance With increasing number of units in the array the sound gradually concentrates in a beam with very small splay angle 7 titi ae i LELE A EELEE Figure 11 1 The radiation at 1 kHz from arrays with increasing number of units from a single unit to 11 units 1 3 5 7 9 and 11 11 107 With 7 units in the array the sound radiation in the octave bands from 250 Hz to 8 kHz is shown in fig 11 2 2H i ie we s D He we J amp e G e Figure 11 2 The radiation in octave bands from 250 Hz to 8 kHz for a line array with 7 units Figure 11 3 Similar to fig 11 2 but the array is bent see Table 1 In order to increase the splay angle to fit an audience area it is usual to apply different elevation angles to the units and thus creating a
32. List at the Source Receiver List e Grdoffering a calculated map of room acoustical parameters if a grid has been specified from the Define grid Menu Setup a Multi point response and run it e Activate source 1 in job one source 2 in job two source 3 in job three and all three sources in job four e Turn on the muti option for the jobs 1 to 4 in order to calculate the point responses for the four receivers you have defined Notice how the active sources are displayed in the 3D Source receiver display as you scroll through the Job list viewing results When the calculation has finished select job number 4 in the job list and click the view multi button to view the multi point response results To learn more about the results and options available in this window press Fi You may also select the page of interest and investigate the dropdown menu which then appears in the top of the program window You can view the multi point response results for each of the four jobs by first selecting the job in the Job List then clicking the view multi Point response button If the Grid option had been checked and a receiver grid had been defined you would be able to view Grid Response results as well This topic will be covered below I befine a receiver grid and calculate grid response Enter the Define Grid menu and select the floor surfaces surface 1001 and surface 1002 Specify the Distance between receivers tO 2 metres then click the S
33. M A 1992 General Metatheory of Auditory Localisation Preprint 3306 of the 92nd Audio Engineering Society Convention Vienna Ingerslev F 1949 L rebog i bygningsakustik for Ingeni rer in Danish Copenhagen Teknisk Forlag Ingerslev F amp Petersen j 1953 Lydabsorberende materialer in Danish Arkitektens Ugehefte no 3 Insul n d Retrieved June 16 2011 from Marshall Day Acoustics http www insul co nz Knudsen V O amp Harris C M 1950 1978 Acoustical Designing in Architecture Acoustical Society of America Kristensen J 1984 Sound Absorption Coefficients Measurement evaluation application Note No 45 in Danish H rsholm Denmark Statens Byggeforskningsinstitut Malham D 2005 January 21 Home page for Ambisonics and related 3 D audio research Retrieved June 16 2011 from Music Technology Group The University of York http www york ac uk inst mustech 3d_audio Meyer E Kunstmann D amp Kuttruff H 1964 Uber einige Messungen zur Schallabsorption von Publikum in German Acustica 14 119 124 Naylor G M amp Rindel J H 1994 Odeon Room Acoustics Program Version 2 5 User Manual Publication No 49 Lyngby The Acoustics Laboratory Technical University of Denmark Ondet A M amp Sueur J 1995 Development and validation of a criterion for assessing the acoustic performance of industrial rooms J Acoust Soc Am 97 1727 31 Oppenheim A V amp
34. ODEON will use this information in order to make corrections for signal delay due to difference in distances from individual loudspeakers to the receivers if the Compensate speaker delays Option is checked and in order to compensate for difference between the angles which are covered by each two loudspeakers if the Parameterization Option is checked Even though ODEON performs these compensations it is recommended to use a speaker layout with as equal angles between the speakers as possible and if possible with left right symmetry Check that labels displayed in the map of loudspeakers is in agreement with the loudspeaker coordinates entered then if this is the case close the Define speaker rig dialog The Auralisation setup dialog is still open and it may be a good idea to save the defined speaker rig just defined to a separate archive file it may be needed at a later point e g if moving ODEON to another computer upgrading the program etc A note on mapped speaker rigs Surround sound files can be mapped by ODEON if this option has been selected in the Define speaker rig dialog An example of a mapped file may be a 5 1 surround file which contains 6 channels that should be feed into front left right left back right back and subwoofer channels If loudspeaker system surround soundcard and its setup match this then the Signals will automatically end at the right places In order to achieve a high degree of compatibility between soft
35. Open the JobList shortcut ctri shift 3 e Calculate all jobs in the JobList shortcut ait a e Once the calculations have finished in the Auralisation Display play the various tracks shortcut alt s These auralisation samples include many setups that tells ODEON how jobs and wave files Should be combined into a few final mixes It is likely that you will want to listen to auralisation in other receiver positions than the predefined ones The fastest way to do this e Make a copy of the file set using the File Ccopy Files menu entry just include room files when prompted e Enter the Source receiver list Shortcut shift ctr s and change the coordinates of the predefined receiver double click the receiver in the receiver list e Open the JobList Shortcut ctri shift 3 e Calculate all jobs in the JobList Shortcut alt s The anechoic recordings have been created by Helsinki University of Technology For use of the anechoic orchestra recordings delivered with the software please see section 8 of the license agreement 2 28 Other facilities in ODEON Apart from the features demonstrated in the above tour ODEON also contains facilities for Calculation of transmission through walls this issue is covered in Appendix C Copying the project files generated by ODEON available from the Files menu item Deleting calculation files or result files available from the Files menu item Archiving project files in one single compressed
36. SPL dB values as entered in the polar plot table adding the equalization values entered This option is typically used if the source is a loudspeaker e If Calibrated source iS Selected ODEON will add the equalization if entered then shift the resulting SPL s of the source in order to obtain a reference sound power level of O dB re 10 Watt at the selected Calibration frequency band typically 1kHz This calibration type is typically used when a generic source with an adjustable level is needed for calculations such as the OMNI Or SEMI directivity pattern e If Sensitivity calibration is selected the SPL s of the source will be shifted in order to obtain the SPL in dB on front axis of the source at the distance specified as Ref distance metres at the selected Calibration frequency Dand This calibration type is typically used if the free field sound pressure level measurements are available for a natural source Maximum dynamic range The minimum level will be Max level minus Maximum dynamic range If the range is large the display may be difficult to interpret view in the directivity viewer The source will usually have its max levels on its axis Text format Normally the text format should not be necessary to use as most common sources are defined already in ODEON or available on www clfgroup org The data entered in the text format should be in relative calibration across frequencies but need not be in any absolute
37. Schafer R W 1989 Discrete Time Signal Processing J Prentice Hall International Parati L amp Otondo F 2003 Comparison of Directional Sources in Simulating a Soprano Voice Proceedings of the Stockholm Music Acoustics Conference SMAC 03 Stockholm Sweden Parkin P H Humphreys H R amp Cowell J R 1979 Acoustics Noise and Buildings London Faber and Faber Petersen J 1983 Rumakustik in Danish H rsholm Denmark Statens Byggeforskningsinstitut Pierce A D 1974 Diffraction of sound around corners and over wide barriers J Acoust Soc Am 55 941 955 Press W H Flannery B P Teukolsky S A amp Vetterling W T 1990 Numerical Recipes in Pascal The Art of Scientific Computing Cambridge University Press Rindel J H 1986 Attenuation of Sound Reflections due to Diffraction Proceedings of NAM 86 pp 257 260 Aalborg Denmark Rindel J H 1992 Acoustic Design of Reflectors in Auditoria Proceedings of the Institute of Acoustics vol 14 Part 2 pp 119 128 Rindel J H 1993 Modelling the Angel Dependent Pressure Reflection Factor Applied Acoustics 38 223 234 Rindel J H 1995 Computer Simulation Techniques for Acoustical Design of Rooms Acoustics Australia pp 81 86 Rindel J H 1997 Computer simulation techniques for the acoustical design of rooms how to treat reflections in sound field simulation Proceedings of ASVA 97 pp 201 208 Tokyo
38. Surface is created The syntax of the Box statement is Box lt Number gt lt Length gt lt Width gt lt Height gt lt T B N gt lt optional name gt lt Number gt A unique number from 1 to 2 147 483647 for identification of the first point and Surface in the Box Using the same number but with negative sign defines the box and its counterpart mirrored in the XZ plane Y 0 A Box will take up several point and surface numbers which must all be unique lt Length gt Length is oriented in the X direction on the Figure lt Width gt Width is oriented in the Y direction on the Figure lt Height gt Height is oriented in the Z direction on the Figure lt T B N gt The 7 B N parameter specifies whether the Box should have a top and or a bottom The options are T B TB and N for none 12 161 Insertion point The insertion point of the Box is always the centre of the floor bottom surface Connection points The four foot points in Box are stored in PlistA The four top points in Box are stored in PListB The Box example shown was generated with the following code BoxStatement par HH const L6 const W 4 const H 2 7 Box 1 LWH TB Walls floor and ceiling HHH The Cylinder statement The Cylinder statement defines a cylinder shell with or without top and bottom The statement may typically be used for modelling cylindrical room or columns The Cylinder2 statement which creates a cylinder of the calotte
39. a full cone is generated Positive revolution angles are defined counter clockwise Connection points The right side vertical points in Dome2 are stored in PlistA The left side vertical points in Dome2 are stored in PlistB In the special case where the revolution angle is 180 all points are stored in Plista and the number of vertical subdivisions is stored in ONVert The example shown was generated with the following code 12 165 HH Const N 16 Const W 10 Const H 3 Const L 10 Dome2 1 N W H 270 Dome calotte HHH Hint The cylinder can be made elliptical using the MScale statement DebugIsOn and Debug The debug options are useful when creating large or complicated geometries in the ODEON par format Using these facilities can speed up geometry loading when loaded for preview only and allow debugging of parameter values in geometry files DebugIsOn is a Boolean which can be set to TRUE Or FALSE the syntax is DebugIsOn lt Boolean gt Typically you will insert the DebugIsOn flag in the beginning of the geometry file in order to investigate parameter values when loading geometry When this Boolean is set to TRUE e ODEON will not prepare the geometry for calculation as result the loading of rooms is speeded up e ODEON will enable debugging of parameters with the Debug statement The syntax for Debug is Debug lt debug string gt In effect anything can be put after the Debug keyword i e you may put a complete cop
40. amp Rindel J H 2008 Danish Acoustical Society Round Robin on room acoustic computer modelling Retrieved from Odeon A S http www odeon dk pdf Classroom 2O0RR pdf Cremer L amp Muller H 1982 Principles and Applications of Room Acoustics London Applied Science Publishers Dietsch L amp Kraak W 1986 Ein objektives Kriterium zur Erfassung von Echostorungen bei Musik und Sprachdarbietungen in German Acustica 60 205 216 Dirac n d Retrieved June 16 2011 from Acoustics Engineering Dual Input Room Acoustics Calculator http www acoustics engineering com dirac dirac htm Fasold W amp Winkler H 1976 Bauphysikalische Entwurfslehre Band 4 Bauakustik in German Berlin Verlag fur Bauwesen 12 128 Furse R n d 3D Audio Links and Information Retrieved June 16 2011 from http www muse demon co uk 3daudio html Gade A C 1997 The influence of basic design variables on the acoustics of concert halls new results derived from analysing a large number of existing halls Proceedings of the Institute of Acoustics Vol 19 Pt 3 Gade A C 2003 Room acoustic measurement techniques Chapter 4 In Room acoustic engineering Note 4213 Lyngby Denmark Acoustic Technology Technical University of Denmark Gardner B amp Martin K 1994 May 18 HRTF Measurements of a KEMAR Dummy Head Microphone Retrieved June 16 2011 from http sound media mit edu resources KEMAR html Gerzon
41. are stored in wave files which may be used on the WEB CD ROM s Power Point presentations etc Click the Toggle button to get to the auralisation display This display is divided into a left and a right part In the left display mono signals are convolved with Binaural Room Impulse Responses BRIR s which have been calculated as part of the Single Point responses this process may be compared to a binaural recording of a mono signal played through simulated source s in the room other types of impulse responses can be used for different playback techniques The right part of the auralisation display two tables is a mixer allowing convolved results to be combined into one wave file allowing multi channel simulations e g stereo setups singer versus orchestra etc The Offline auralisation offers greater flexibility than the real time auralisation allowing full control over which signal to pass through which of the 300 channels available and assigning individual level and delay to each channel If for some reason you need the auralisation output as a wave file it is also the offline auralisation which should be used Single channel simulation First try to create a one channel simulation of a person speaking from source position 1 In the auralisation display select the conv no 1 row and select the voice Sabine Short file in the signal file field this is an anechoic recording of voice stored in a windows wave file residing in the directory
42. azimuth and elevation The information on size of the reflecting surfaces and absorption coefficients are also available as a part of the calculation Binaural filters for headphone playback When the Auralisation setup Create binaural impulse response file Option is turned on reflections are processed in order to create a binaural impulse response BRIR First of all it is determined whether a phase shift should be applied to the reflection based on surface size and absorption coefficients of the last reflecting surface Rindel 1993 Then the reflection is filtered convolved through 9 octave band filters Kaiser Bessel filters the ninth being extrapolated and finally the reflection is filtered convolved through two corresponding directional filters one for each ear Head Related Transfer Functions creating a binaural impulse response for that reflection This process is carried out for each reflection received at 6 84 the receiver point and superposing all the reflections a resulting Binaural Room Impulse Response BRIR for that particular receiver point is obtained The actual order in which the filtering is carried out in ODEON differs somewhat from the description above otherwise the calculation time would be astronomic but the resulting BRIR contains the full filtering with respect to octave band filtering in nine bands as well as directional filtering B format filters for external decoding and Surround filters for loudspeaker p
43. calibration The absolute calibration is an option from within the program as described under the chapter below Creating a new directivity pattern using a text file as input 10 103 The first non comment line of the input file indicates whether the data is for e POLAR set containing horizontal and vertical polar plots for sources where only a horizontal and a vertical plot are known e g a loudspeaker e FULL set for complex sources where directivity data is known for each 10 Azimuth and 10 Elevation e SYMMETRIC set for symmetric sources e g a trumpet The second non comment line in the input file indicates whether the data represents a Natural source such as a musical instrument or a person speaking or if it represent a source such as a loudspeaker which does not include the frequency response of the source signal The purpose of this Boolean is to make auralisation correct for natural sources set NATURAL to e TRUE for sources such as musical instruments e FALSE for sources such as loudspeakers Each of the subsequent lines of the input file should contain sound pressure levels in dB for a complete 180 of elevation from the forward axis to the backward axis The resolution must be 10 hence each line contains 19 values 0 10 20 160 170 and 180 Lines containing comments and empty lines may be inserted anywhere in the ASCII input file as long as they do not come between data items which sh
44. clients etc without worrying about whether they have a PC with a soundcard of a reasonable quality Again when publishing examples make sure that copyrights are not violated You are free to publish examples which are calculated using the anechoic examples supplied with ODEON For the orchestra recordings the conditions as specified in the software license agreement 8 must be observed see p 1 7 Remember to tell the end user to use headphones when listening to the samples 5 71 6 Calculation Principles 6 1 Global decay methods ODEON features two methods for calculating the Global decay of rooms e Quick Estimate Which is available from the Materials List is the fastest method allowing quick evaluation of the effect of changes to materials This method should be considered only as a tool for preliminary results e Global Estimate is the most precise of the two global methods allowing high quality results 6 2 Quick Estimate This method estimates a mean absorption coefficient which is inserted in the Sabine Eyring and Arau Puchades formulas to give an estimate of the reverberation time Instead of simply taking the areas of the surfaces and multiplying by the corresponding absorption coefficients to obtain the total absorption in the room ODEON also sends out particles from the source assuming diffuse conditions thus reflecting them in random directions keeping a count on how many times they hit each surface Surfaces that a
45. cylinder can be made elliptical using the MScale statement 12 163 The Cone statement The Cone statement models a cone Typical use of the Cone statement is for modelling half cone or cone shaped ceilings The syntax for Cone is Cone lt Number gt lt NumberOfSurfaces gt lt Radius gt lt RevAngle gt lt Height gt lt optional name gt lt Number gt A unique number from 1 to 2 147 483647 for identification of the first point and surface in the Cone Using the same number but with negative sign defines the surface and its mirrored counterpart in the XZ pane Y 0 A Cone will take up several point and surface numbers which must all be unique lt Radius gt Radius of the Cone must always be greater than zero lt Revangle gt Revangle Must be within the range 360 and different from zero If RevAngle is 180 a half cone is generated if its 360 a full cone is generated Positive revolution angles are defined counter clockwise lt Height gt The height must be different from zero If the height is less than zero the orientation of the cone is inverted Height is oriented in the Z direction on the Figure The Cone example shown was generated with the following code HHH const N 16 const R 15 const H 10 Cone 1 N R 270 H Cone shaped ceiling HHH Hint The cone can be made elliptical using the MScale statement The Dome statement fe P a The Dome statement generates a full dome half hemisphere covering
46. decimal numbers Parametric sample BoxFromPureNumbers par HHH Pt 1 0 2 0 Pt 2 0 2 0 Pt 3 6 2 0 Pt 4 6 2 0 ceiling points Pt 11 0 2 2 7 Pt 12 0 2 2 7 Pt 13 6 2 2 7 Pt 14 6 2 2 7 Surf 1 floor 1 2 3 4 12 167 Surf 2 ceiling Il 12 13 14 Surf 3 end wall 1 2 12 11 Surf 4 end wall 1 2 12 11 Surf 5 side wall 1 4 14 11 Surf 6 side wall 2 3 13 12 HHH Below the box shaped room is modelled using constants for the definition of W Land H Some of the advantages of using parameters in modelling rooms are that it makes changes to a model much easier allowing reuse and often it will also improve the clarity of a model data Parametric sample BoxFromParameters par The box measures are Width 4 metres Length 6 metres Height 2 7 metres HHH const W 4 const L 6 const H 2 7 Pt 1 0 W 2 0 Pt 2 0 W 2 0 Pt 3 L W 2 0 Pt 4 L W 2 0 Pt Il 0 W 2 H Pt 12 0 W 2 H Pt 13 L W 2 H Pt 14 L W 2 H Surf 1 floor I gt 4 Surf 2 ceiling 11 gt 14 Surf 3 end wall 1 2 12 11 Surf 4 end wall 1 2 12 11 Surf 5 side wall 1 4 14 11 Surf 6 side wall 2 3 13 12 HHH Below the box shaped room is modelled using parameters and symmetric modelling syntax signs on point and surface numbers The symmetric modelling syntax means less typing and less typing errors Parametric sample BoxFromParametersUsingSymmetricModelling par HHH const W 4 const L 6 const H PA Pt 1 0 W 2 0 Pt 2 L W 2 0 12 168 Pt Il 0 W 2 H
47. gt lt MaxCount gt lt X MathExpression gt lt Y MathExpression gt lt ZMathExpression gt Use the CountPt statement to define a series of points using a counter This statement makes use of the predefined counter PtCounter which will run from 0 to MaxCount 1 producing the points with the numbers FirstPointNo tO FirstPointNoe MaxCount 1 Use the PtCounter in the expression of the x y and z coordinates to create the desired differences between the count points Example defining 7 points on a circle with a radius of 10 at Z O metres CountPt 100 6 1 10 CosD PtCounter 360 6 10 SinD PtCounter 360 6 0 Note First and last point in this series of count points are equal redundant This will typically be desirable when using the CountPt statement along with RevSurf statement Defining a single surface using the Surf statement A Surf statement is divided into two lines and must follow the syntax Surf lt SurfaceNumber gt lt Optional Description gt lt ListOfPointNumbers gt The Surf statement is used to define a single surface in some situations with symmetry two surfaces The Surf statement is constructed from two lines one identifying the surface by a number and an optional name and another with a list of corner numbers lt SurfaceNumber gt A unique number from 1 to 2 147 483647 for identification of the surface Using the same number but with negative sign defines the surface and its counter part mirrored in the XZ
48. http autodesk blogs com between the lines 2007 04 autocad 3dsout html as a plug in but it can only be used on Windows XP so if running a later version of Windows unfortunately this may not be an option To install and use the plug in for Windows XP do read this installation note http images autodesk com adsk files readme 3dsout html The support for the pxF file format Drawing eXchange Format allows import of CAD models exported from modelling programs such as CAD package www intelliCAD com Google SketchUp ttp sketchup google com AutoCAD www autodesk com 3DStudioMax http www discreet com cones http www bentley com en US Products MicroStation There may also be other programs around capable of creating geometry data which can be used with ODEON The DXF import engine in ODEON supports a number of CAD entities which can be exported from these programs and imported directly by ODEON without any extra effort Depending on the modelling program used and indeed how it was used different approaches may need to be taken in order to ensure that all or most of the drawing data are exported to the dxf file in a form which can be understood by ODEON If ODEON encounter entities in the import process which ODEON recognizes but doesn t support then ODEON will notify about it The modelling programs should be 3D modelling programs Programs such as AutoCAD LT only have limited support for 3D modelling and
49. in the calculations so the energy losses in the two rooms are determined by the absorption coefficients and reduction indexes as used Odeont 1985 2007 Figure D3 The Transmission Rooms par sample is installed with ODEON The Figure illustrates how transmission data are assigned to transmission walls when transmission walls are composed from a single surface two surfaces and three surfaces Once the room has been loaded into ODEON additional information is available in the Notes editor using the Shift CtrI N shortcut In the Joblist some example setups have been prepared for calculations in source rooms as well as in receiver rooms 12 134 Appendix D Description of XML format for import of array loudspeaker data The ODEON XML format for array loudspeakers allows import of array parameters that specifies how a number of transducers are combined together to form an array loudspeaker Arrays can be beam steered a digital filter being assigned to each transducer or a more conventional array where each transducer is feed directly or through an equalizer with a delay etc External files needed a directivity pattern for each transducer Currently the following directivity formats are supported Common loudspeaker format cFi cF2 and ODEON s native format sos The frequency range needed by ODEON covers the full octaves from 63 Hz to 8 kHz however in order to make the format as versatile as possible e g for future use or
50. is simply repeated for each receiver When more than one source is involved the response at a given receiver is simply the sum of the responses from the individual sources each delayed appropriately if a delay is applied to the source 6 74 ODEON automatically takes care of handling which of the calculations and result files are currently consistent with user entered data erasing those that are no longer valid Thus in some situations you may experience that Rays tracing Calculations have already been done are still valid in other cases they have to be recalculated The Early Reflection method Early reflections in ODEON are are reflections generated by k point sources while the reflection order is less than or equal to the Transition order specified in the Room setup For each of the image sources found in the Early part of the receiver independent calculation ODEON checks each to determine whether it is visible from the receiver Images may be hidden because walls in the room block the reflection ure path to the receiver or we because the receiver falls ar outside the aperture Sa Se formed between the image o s source and the surface i generating it Figure 6 1 illustrates the concept of visible and hidden image Figure 6 1 Visible and invisible images Images S1 and sources If an image is 21 are visible from R while S2 S3 and S12 are not found to be visible then a reflection is added to the refle
51. it becomes a holster outlined by the edges of the extrusion surface if so desired this holster can have a bottom and a top Odeon 1985 2004 X In the extrusion modeller it is possible to make one drawing which contains multiple extrusion surfaces each described by a 2D outline a simple drawing and the line properties drawing depth extrusion height bottom check mark top check mark and a name If the extrusion is created in the XY plane then one extrusion surface may form a volume with walls and optional floor and ceiling odeono1985 2004 whereas other extrusion surfaces define tables chairs or screens For some geometry it may be more appropriate to draw the geometries in one of the other main planes XZ and YZ planes AS an example the auditorium par model in the Figure has been modelled in the XZ plane using separate extrusion surfaces for the room the wall with windows holes the table and the windows Odeon 1985 2004 The Extrusion Modeller and file formats The output from the extrusion modeller comes in two formats the extrusion model can be saved in its own native format in an oes file This file can be edited and extended at a later point in the extrusion modeller e g if wishing to change width of the auditorium above to change some of the points in the drawing or to add other features 3 44 The other format is the ODEON par format which is loaded into ODEON for calculations The param
52. list and click the view grid button to view the grid results To learn more about the results and options available from this display press F1 EA Calculate Reflector Coverage Enter the Define reflector surfaces menu and select the podium ceiling surface surface 3001 Then click the Calculate reflector coverage button on the main toolbar to calculate the reflector coverage for the selected surface s Reflector coverage Calculates the coverage provided by chosen reflecting surfaces at the first order reflections or up to fifth order if so desired using the dropdown menu or shortcut keys 1 through 5 This is an efficient tool for investigating whether the receiver area is covered by the reflectors or not and if the reflectors are positioned correctly The 3DBiliara display may also be useful for this purpose 3D Investigate Rays The 3D Investigate Rays display visualises the ray tracing as it is carried out during any point response calculation By default its calculation parameters are also set up as the parameters used for the point response calculations Single Point Multi and Grid This display is a very valuable tool for testing new room models e g to detect missing or misplaced surfaces It may also give an impression of what is happening in the calculations e g the effect of the scattering assigned to the surfaces Click the ok button then click the Single forward button a few times and note the behaviour of the ray tracin
53. not been investigated in depth which scattering coefficient at the mid frequency 707 Hz should be used for various materials However initial investigations indicate that the following magnitudes may be sound Table 1 Suggested scattering coefficients to use for various materials The given values are for the middle frequency at around 700 Hz to be assigned to surfaces in ODEON Suggestions may be subject to changes as more knowledge on the subject is obtained Structures with high roughness should be modelled as planar surfaces The lack of detail can be compensated by choosing an appropriate scattering coefficient according to the depth of the structure see Fig 6 4 Scattering coefficient s 10 100 Depth of structure mm Figure 6 4 Scattering coefficient should be chosen from depth of structure 6 78 Ss Scattering due to diffraction In order to estimate scattering due to diffraction reflector theory is applied The main theory is presented in Rindel 1986 Rindel 1992 The goal in these papers was to estimate the specular contribution of a reflector with a limited area given the basic dimensions of the Surface angle of incidence incident and reflected path lengths Given the fraction of the energy which is reflected specularily we can however also describe the fraction sg which has been scattered due to diffraction A short summary of the method is as follows For a panel with the dimensions w above the upp
54. of reflections in the late part of the decay If the predicted decay curves Decay curves are displayed in the Single point response results in ODEON Auditorium and Combined has Suspicious spikes you may try to increase the number of late rays accordingly The actual number of reflections per millisecond used in the calculation of a point response is included in the calculated parameters of the Single point Multi point and Grid response results if this predefined parameter is included and Set to Visible in the Room Acoustics Parameter List for reliable results the reflection density Density reflections should be greater than 25 ms or so If multiple sources with similar source power are visible from all most receivers then the Number of Late rays May be decreased significantly If the room model contains strong decoupling effects or uneven distribution of the absorption it is desirable to increase the Number of late rays even if the calculated reflection density seems high enough It is recommended to experiment with different Number of late rays and study the decay curves in Single Point Responses If many surfaces are added to a model in between calculation it is recommended to re specify the Number of late rays too The ODEON algorithms are hybrid methods based on the Image source method and ray radiosity for the early part of the energy and ray radiosity for the later part of energy Therefore there is also a Number of early rays Spe
55. or even impossible to obtain results at this precision and a poorer one will probably also be satisfactory for most purposes Parameter Definition Subj limen ISO 3382 1 2009 and IEC 60268 16 2003 for STI T30 S Reverberation time derived from 5 to 35 dB of the decay 5 rel curve EDT s Early decay time derived from 0 to 10 dB of the decay curve Dso Deutlichkeit definition early 0 50 ms to total energy ratio Cso dB Clarity early 0 80 ms to late 80 energy ratio 1 dB abs gravity time 10 m distance LF Early lateral 5 80 ms energy ratio cos lateral angle STI RASTI Room acoustical parameters and their subjective limen as given by Bork Bork 2000 and Bradley Bradley 1986 Example 1 If the real G value is 1 dB and the simulated is 1 9 dB then the difference is not noticeable Example 2 If the real LF value is 12 and the simulated is 17 the difference is just noticeable Note When comparing measured parameters to the ones simulated it should be kept in mind that the measured parameters are not necessarily the true ones as there are also uncertainties on the measured result These errors are due to limited tolerances in the measuring equipment as well a limited precision in the algorithms used for deriving the parameters from the measured impulse response or similar errors if results are not based on an impulse response measuring method There may also be errors due to i
56. plane Y O The surface number may be defined using mathematical expressions lt Optional Description gt A string displayed and printed for easy identification of the surface Could be something like Main floor lt ListOfPointNumbers gt Each surface may be bounded by between 3 and 500 corners which all lie in a plane Corner numbers refer to the corners which must have been defined e g using the Pt or CountPt statements before using the surface statement The order of listing must be as obtained by travelling around the surface s edge in either direction The list of corner point numbers must be on the same line A room may contain up to 10000 surfaces Example 1 surface made from point 1 2 3 4 Surf 100 floor 1 2 3 4 Example 2 surface made from point 1 2 10 11 12 13 14 4 5 Surf 200 Ceiling 1 2 10 gt 14 4 5 If there is a need to programmatically build a list of points this can be done using the PList and ResetPList statements 12 150 Building lists of points using PList and ResetPList The PList and ResetPList statements are used in special cases together with the Surf statement Twelve lists are predefined namely PListO to PList9 and PlistA and PListB which are handled automatically by ODEON when modelling af Box and other Solids The PList statements allow to programmatically construct a list of points e g a list like 100 110 120 130 140 150 160 170 180 190 200 this can be done using a for end con
57. points being moved to be positioned exactly at the intersection of the grid lines In special cases the point can also be inserted at only one grid line when the other coordinate is that of an existing point see below snap to existing points Snap to existing points Snap to existing points enables points to be precisely located on either or both reference coordinates of existing points The snap point The snap point is a special case of snap to existing points In some cases you may want to move a surface to a precise location e g 0 33 0 46 not being a point on the grid nor an existing point of another surface In that case e Create a new surface e Click the approximate position of the reference point e Change the coordinates to the exact position e g 0 33 0 46 in the Point editor J Press Insert OF Esc to finish editing the surface the point will appear with the mark Snap point e Select the fix point in the surface to be moved left mouse button and move it to the location of the snap point Do note that Snap to existing coordinates Option Must be checked Once the surface has been moved the surface containing the snap point may be deleted this is not a strict requirement as surfaces containing only one point will not be transferred to the par format to be used in ODEON 3 46 Coordinate snapping When entering new points clicking the mouse coordinates of points will be truncated to the nearest snap e g t
58. relationship between surface numbers and the material assigned to that surface inside the ODEON program The Auto option is very useful in combination with loop constructions see description of the for end constructs later on Typing PtAbsRef after the value assigned to NumbOffSet forces absolute number references for points while using the specified offset on the numbers of surfaces this is explained later Example on the use of NumbOffSet creating surface 101 containing the points 101 to 104 and surface 201 containing the points 201 to 204 NumbOffSet Par HHH NumbOffSet 100 Pt 1 0 1 0 Pt 2 0 1 0 Pt 3 1 1 0 Pt 4 1 1 0 Surf 1 A surface 1 2 3 4 NumbOffSet NumbOffSet 100 Pt 1 0 1 1 Pt 2 0 1 1 Pt 3 1 1 1 Pt 4 1 1 1 Surf 1 Another surface 12 148 I 2 3 4 HHH Example creating point 1 4 and surface 1 setting NumbOffSet to Auto then creating Point 5 8 and surface 5 HHH Pt 1 0 1 0 Pt 2 0 1 0 Pt 3 1 1 0 Pt 4 1 1 0 Surf 1 A surface 1 2 3 4 NumbOffSet Auto Pt 1 0 1 1 Pt 2 0 1 1 Pt 3 1 1 1 Pt 4 1 1 1 Surf 1 Another surface 1 2 3 4 HHH Defining a point using the Pt statement Use the Pt statement to define a single point The syntax must be as follows Pt lt Point Number gt lt XMathExpression gt lt YMathExpression gt lt ZMathExpression gt Example defining point number 100 in x y z 1 1 1 Pt 100 1 1 1 Hint Point number and coordinates can be written using mathematical expressions allowing grea
59. rest of the energy The early scatter rays are handled in a way which is indeed inspired by the way in which ODEON simulates surface sources actually each time an image source is detected ODEON will simulate a surface source which will emit Number of early scatter rays from the image source surface The early scatter rays will be traced from the current reflection order and up to the transition order At each reflection point of the early scattering rays including the point of origin a secondary scattering source is created 6 75 The Late Reflection method All reflections that are not treated by the early reflection method are treated by the late reflection method At all the reflection points of late part of the receiver independent part of the ray tracing a small secondary source is generated for reflections above the Transition order This secondary source may have a Lambert Lambert Oblique or Uniform directivity depending on the properties of the reflection as well as the calculation settings ODEON checks each secondary source to determine whether it is visible from the receiver The late reflection process does not produce an exponential growing number of reflections with respect to the time as the image source method would suggest but keeps the same reflection density in all of the calculation allowing for reasonable calculation times The attenuation of a secondary source is calculated taking the following into account
60. set in the Options Program setup Auralisation Wave signal file Directory TO play the selected signal file make sure this cell is selected then press the alt s shortcut or the Play wave button Adjust the Rcd Lev recording level to 30 dB Then arrow right to the Job no column and select Job no 1 from the dropdown list Exit the job no cell but stay on the same row and the corresponding 3D Source Receiver view iS updated to show active sources etc Click the Run al button to convolve the signal with the BRIR If other calculations e g point response calculations have to be carried out before the convolution is allowed ODEON will manage this automatically Play auralisation file through headphones Once the calculations have been carried out click the Play wave result button and listen to the result through headphones If you have selected the signal Sub Path or the Signal file column in the Convolve BRIR and Signal file table the anechoic input file is played If any other column in this table is selected the convolved result file is played Ed Convolving BRIR s with signals and mixing signals In the following we will assume that you have a stereo recording called myStereoRecording wav stored on your computers hard disk in a 16 bit resolution sampled at 44100 Hz Toggle to the Auralisation display ALT T First step is to set up two mono playbacks one playing the left channel of the stereo signal another playing the right cha
61. shown STI This is the most known form of STI derived for an average gender independent voice spectrum STI Male and STI Female These are STI values adapted for male and female speakers according to their speech spectrum Both the contribution of each Octave Band to the STI and the information overlap from one band to another is taken into account STI Expected The expected STI value is calculated on a theoretical basis taking into account the reverberation time of the room and the background noise but not the explicit shape of the impulse response The STI Expected is the value of STI if the field in the room was totally diffuse and the energy decay was exponential RASTI An abbreviation of Rapid STI it is considered an obsolete parameter in the revised IEC 60268 16 2003 standard It is based only on two Octave Bands 500 Hz and 2000 Hz and provides a faster and simplified calculation of the STI DL Rate of Spatial Decay Rate of spatial decay is the decay of sound pressure level per distance doubling DL is calculated according to ISO 14257 2001 The DL parameter is intended to characterise the acoustic performance of workrooms The values to be expected for the DL parameter is according to Ondet amp Sueur 1995 1 3 dB for reverberant rooms and 2 5 GB for ideally treated rooms The design criterion for DL is set to 3 5 dB or better according to ISO 11690 1 1996 The DL parameter is calculate
62. the word Mddd where ddd is a floating point number then localization enhancement was applied to the HRTF s Zang Tan amp Er 1998 This means that frequency dips and notches in the individual HRTF s have been exaggerated in order to improve the directional cues in the HRTF s The M factor determines how much the dips and notches have been exaggerated If M is O then the effect is neutral a value of 3 0 improves localization without too much undesired colouration A M value greater than 3 0 does not seem to give any noticeable advantages whereas a value less than 3 0 gives less colouration The enhancement algorithms are further developments of those used in earlier versions of ODEON as a result the M factor can be set as high as 3 0 allowing a significant improvement of the 3D experience through headphones without noticeable drawbacks A When an A is appended after the M factor this tells that Minimize colouration effects diffuse field approach was not enabled so the HRTF were optimized for Anechoic conditions i e no reflections present If no A is found in this place in the name then ODEON has attempted to Minimize colouration effects The enhancements applied may give some colouration effects because some frequencies are amplified for individual directions When this option is checked ODEON will try to accomplish that colouration is kept at a minimum in a multi reflection environment that is the average frequency response for all
63. the Single forwara button a few times and note the behaviour of the ray tracing 3D Billiard The 3D biliara display is a tool that can be used for investigating or demonstrating effects such as scattering flutter echoes or coupling effects A number of billiard balls are emitted from the source and reflected by the surfaces in the room To speed up the process set the Dist per update to a higher value To visualize a flutter echo a large Number of billiard balls Should be used e g 10000 balls It s easier to visualize a flutter echo if rays are only emitted in the relevant plane XZ YZ or XY If the geometry is complicated it may be hard to see the billiard balls in that case toggle parts of the geometry off using the T shortcut 2 52 Other facilities in ODEON Apart from the features which have been demonstrated in the above tour ODEON also contains facilities for Measurement facilities for room acoustics simulations which is covered in Chapter 12 Calculation of transmission through walls this issue is covered in Appendix C Copying the project files generated by ODEON available from the File menu item Deleting calculation or result files available from the File menu item Archiving project files in one single compressed zipped file for efficient and safe storage or for easy posting by e mail available from the File menu item Tools for detecting errors in a new model e g warped or overlapping surfaces avai
64. the Windows Start Contro panel Add remove programs feature If keeping an earlier version be careful not to mix the use of old and new versions although we do strive to maintain forward compatibility we cannot guarantee that a room which has been loaded into a new version of ODEON will also load into an older version without problems Upgrading from version 6 and earlier If you upgrade from a version earlier than 6 then we do recommend that you read carefully through the manual as if you were a newcomer to ODEON There are a substantial differences between the early versions of ODEON and the ODEON software as it is today modelling has been made easier calculation principles has been enhanced and a huge amount of new features has been added Project files The only project file from versions earlier than 3 0 being fully compatible is the surface file sur The rest of the project files are no longer valid And even though the sur format is still valid it is not recommended to model rooms in this format The par format is a much more efficient format Upgrading from ODEON 4 5 and 6 to ODEON 7 and later If you are having problems loading a room which was created and worked fine in one of the above listed versions of ODEON this is probably due to a change that has been made to the Surface numbering mechanism applied in ODEON The numbering mechanism has been changed slightly in order to avoid a conflict which appeared when usin
65. the absolute level of natural source e g a human voice When selecting the NON CALIBRATED source you are allowed to enter equalising electric losses zero for natural sources and a sensitivity at a selected frequency band zero for natural sources The addition of electrical sensitivity electrical input power and electrical loss values completes the data necessary to generate a source directivity file directly readable by ODEON 3 or later 10 105 10 106 11 Line array sources This section gives an introduction to the use of the line array option in ODEON The examples are chosen in order to demonstrate some basic properties of line arrays and they are not representing recommended solutions It is a delicate process to adjust and optimize a line arrays sound system for a particular room and the Knowhow and technique needed for that is beyond the scope of this manual 11 1 Stacking the units By stacking a number of loudspeaker units on a vertical line with a constant distance d between the centres of the units the first thing to note is that the splay angle changes The sound is radiated in a more or less concentrated beam and the splay angle narrows in when the array gets longer With N units the length of the array is L d N 1 and this should be longer than one wavelength in order to obtain the narrowing of the spay angle This can be expressed by a lower limiting frequency C C J z Z L d N l where c
66. the receiver path in the DL calculation In this case the following solution is recommended e Make a copy of the room using the FilelCopy files option e g copy a room called MyRoom to MyRoomDL2Path and load the new copy when prompted for during the copy process e Delete receivers that are not wanted in the receiver path e Define the receivers needed e Finally make the Multi Point response calculation with the appropriate point source activated in the particular job ISO 3382 3 Open plan offices parameters For these calculations the source is required to be assigned the 1s03382 3_Omni sos directivity file The following parameters are supported Spatial distribution of STI This curve shows how the decrease of speech transmission index as a function of the distance from the source Distraction distance rp Distance from the speaker where the speech transmission index falls below 0 50 Above the distraction distance concentration and privacy start to improve dramatically Privacy distance rp Distance from the speaker where the speech transmission index falls below 0 20 Above the privacy distance concentration and privacy are experienced very much the same as between separate office rooms Spatial decay rate of A weighted SPL of speech D2 s This curve shows the decrease of the A weighted sound pressure level per distance doubling from the sound source which emits noise with the sound power spectrum of normal speech A weig
67. their individual area because the individual surfaces do not provide any significant edge diffraction In these cases the method can be bypassed by setting the surface Type tO Fractional in the Materials List see chapter 4 When setting the Type tO Fractional the surface area used for calculating the Reflection Based Scattering Coefficient is determined from the box subscribing the room rather than the individual surface if the construction part which the fractional surface is part of is considerable smaller that the room box scattering might be underestimated and a higher scattering coefficient should be assigned to the surface Figure 6 5 A typical diffuser depth interior margin entered by user determines which parts of the geometry should be considered exterior of a room thus limiting the scattering of the boundary surfaces which can not be considered freely suspended at the lowest frequencies 6 5 Oblique Lambert In the ray tracing process a number if secondary sources are generated at the collision points between walls and the rays traced It has not been covered yet which directivity to assign to these sources A straight away solution which is the one ODEON has been applying until version 8 is to assign Lambert directivity patterns that is the cosine directivity which is a model for diffuse area radiation However the result would be that the last reflection from the secondary sources to the actual receiver point is handled
68. thin barriers In rooms where all surfaces have moderate absorption coefficients e g below 0 8 0 9 the contribution from diffracted sound over a screen around a corner or around a book shelf is not likely to change results noticeably however in rooms such as an open plan office with very absorbing ceiling or in outdoor situations diffraction around edges may play an important role 6 7 Radiated rays from a source In ODEON Combined and Industrial version only three different kind of sources are available the point the line and the surface source 6 83 Point Sources For Single Multi and Grid response calculations and for the 3D Investigate Rays and 3D Billiard displays rays are radiated in directions distributed as evenly as possible over a solid angle To obtain the even distribution ray directions are emitted in directions given by the Fibunacci spiral Using a spiral also ensures that there will be no preference towards or away from e g horizontal rays as might be the case if rays were radiated from a number of e g horizontal rings For Quick Estimate ANd Global Estimate the radiated directions are chosen randomly allowing the calculation to be finished after any ray without getting a very uneven distribution of radiated directions Surface Sources and Line sources Industrial and Combined versions only For these source types points of origin for the rays and their initial directions are the same no matter the calculati
69. this Agreement shall be declared void or unenforceable the validity of this Agreement and all other provision shall not be affected ODEON product Support and service is only provided to registered ODEON users with a valid support agreement 1 8 1 9 Contents IAT OGUN e E E E wane tars aero when ta wRAeENaEAeR ta oeRrN Na E 1 4 END USER LICENSE AGREEMENT cccccceeeccecccecceeeeeeeeeeeeeeeeeeeeeeaeeueeeeaeneueuaaauaananaaggs 1 6 CONE TE waceoeeitseceressscctcnsennsisueiae E E EE E E E 1 10 1 Installing and running the program s ssssssssssssnrsrrnnsnrenrnrsnrnrrrrnnrrrnnrnrnnenrenrnrenno 1 13 1 1 Installing and running the program n sssssssssssssrsrsnrsrenrsnrnrerennsnrnnenrnrenrenenernne 1 13 1 2 Upgrading from previous verSionS s sssssssssrssrssrrnrrnnrnrrnnrnrrnnrnnrnrrnrenrrnrrnnrnnn 1 13 Joora dino TO Vo On L rara a A A E AEE E E E AA E 1 13 Features introduced with Version 10 cc ccccccccccceee cence eee e eee e nese eeeeeeeeeeeeeeeeeeeeeseneneas 1 13 Features introduced with Version 9 1 cccccceeeeecceeceeeeeennnneeeeeeeeeseeeeensennaanneeeeesenegs 1 13 Upgrading from versions earlier than Version 8 cccccccceeeeeeeeeeeeeee seen eee eeeeeeeeenaaanaes 1 14 Major WO Gi ad Erraina anena a aa aneeitusiaeieeeidusieusnarsaneanee 1 14 Upgrading from version 6 and earlier cceeseeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeaeeneeaaaanags 1 14 Upgrading from ODEON 4 5 and 6 to ODEON 7 and later
70. time limited Update time limitation If current license is time limited then it is possible to update the time license i e to request additional run time Remove time limitation If the current license is time limited it is possible to request the time limitation to be removed 1 16 2 Short guided tours This chapter will give an introduction to the use of the ODEON program Depending on the edition purchased the guided tour differs The combined and Auditorium editions are covered in section 2 1 The industrial edition and the Basics edition are covered in sections 2 2 and 2 3 respectivelly As a supplement to the guided tour we recommend that you watch some of our video tutorials on YouTube Please find the links at www odeon dk tutorials acoustic simulation The measurement system included with ODEON 12 is not covered in this guided tour please refer to chapter 12 Buttons hints and menus The most common operations can be carried out using buttons Hovering the mouse over a button will display a hint telling the function of that button You can also operate the program using menus and shortcut keys Less common operations are available from the dropdown menu in the top of the ODEON application window menus will change in order to facilitate the currently selected window or indeed the selected tab sheet in the currently selected window If looking for a facility in a window it is quite likely that it can be found in the dropdown
71. to all Surfaces on a layer in one operation Exporting a geometry from ODEON to IntelliCAD or AutoCAD When ODEON exports surfaces containing more than 4 points each these surfaces are exported using the 3ppPoLy entity whereas all other entities are exported using the 3pFac entity The 3DPOLY will appear as 3DPOLy lines in the CAD program and does not respond to the HIDE and RENDER commands like entities such as 3DFACE do However using the REGION command it is possible to convert 3DPOLY s into REGION s which do respond to the HIDE and RENDER commands Before exporting from the CAD program Remember that BLOCK s are not supported by ODEON BLOCK s containing relevant 3D info must be exploded using the EXPLODE command in the CAD program in AutoCAD this may also be done by exporting the file to the 34s 3D Studio Max format and importing it again as described in the section on 3DSOLIDS 3DSOLID REGION and Bopy entities are not supported by ODEON try using one of the approaches listed above in order to make the geometry compatible A final remark is that it is always a recommended practice to make backup copies of your CAD files before making any conversions Performing the import in ODEON To import a DxF file e Select FileslImport from file dxf 3ds cad Or Simply drop the file on the Canvas of ODEON e Specify the input file e g MyCADRoom dxf e Specify the destination file e g MyCADRoom Par 3 53 Once the file names have
72. when defining new natural point sources The old versions of the files are kept in old_sos a subdirectory to the pirfiles directory If you wish to use the old directivities in old existing projects then open the Source receiver list and click the Repair broken directivity links button shortcut ctri L 10 101 Samples on natural directivity patterns TLKNORM TLKRAISE and Soprano ref 42 The TLKNORM source type corresponds to a male talker with a normal vocal effort The gain and EQ fields in the Point source editor inside ODEON should be set to zero This source is also a reasonable approximation to a female talker except that the 63 and 125 Hz band should be ignored To simulate a trained talker addressing an audience in a raised voice use the TLKRAISE source This has the same directivity aS TLKNORM but the levels in the eight octave bands are respectively 2 2 5 7 9 8 6 and 6 dB higher The directivity pattern Of Soprano ref 42 is the directivity of a soprano singing opera Parati amp Otondo 2003 10 3 Common loudspeaker format CF1 and CF2 files ODEON 8 and later supports the Common Loudspeaker Format which is an open format for loudspeaker data Supported by several loudspeaker manufacturers as well as manufactures of software programs such as ODEON The Common Loudspeaker Format was developed and is maintained by the CLF group at www clfgroup org It is an open though secure file format for loudspeaker performanc
73. which should be set to max manually by the user However it is likely also to have a dedicated microphone amp boost 12 114 which can typically be set in the range O to 30 dB be sure to set it so a desirable response is achieved If using a different setting in your measurements than used in the calibration be Sure to adjust the gain in the measurement setup accordingly Disable system sounds in mixer This is important so that no disturbing sounds pop out suddenly during a measurement Setting up your sound card correctly Set up your sound card correctly for use with the ODEON measurement system Many soundcards are equipped with advanced features such as noise cancellation echo cancellation reverberation which may be useful when using internet video conferencing or listening to music However any such feature is highly undesirable when using the sound card for room acoustics measurements Thus should be disabled For example many PCs come with the built in Realtek audio device You can access the global settings for this device within from the Realtek Audio Manager The noise suppression ANC echo cancellation options for the recording device microphone should be deactivated w Measure Impulse Response y Measure impulse responses sinusoidal sweep eos The Measure Impulse Response SHIFT CTRL L window can aia sar aes be accessed also from within the Tools menu You can specify the sweep length i e the duration of the
74. with 100 scattering no matter actual scattering properties for the reflection This is not the optimum solution in fact when it comes to the last reflection path from wall to receiver we know not only the incident path length to the wall also the path length from the wall to the receiver is available allowing a better estimate of the characteristic distance a than was the case in the ray tracing process where drei was assumed to be equal to dine SO which directivity to assign to the secondary sources We propose a directivity pattern which we will call Ob ique Lambert Reusing the concept of Vector based scattering an orientation of our Lambert sources can be obtained taking the Reflection Based Scattering coefficient into account If scattering is zero then the orientation of the Oblique Lambert source is found by Snell s Law if the scattering coefficient is one then the orientation is that of the traditional Lambert source and finally for all cases in between the orientation is determined by the vector found using the Vector Based Scattering method 6 81 Shadow zone Oblique angle Figure 6 6 Traditional Lambert directivity at the top and Oblique Lambert at the bottom Oblique Lambert produces a shadow zone where no sound is reflected The shadow zone is small if scattering is high or if the incident direction is perpendicular to the wall On the other hand if scattering is low and the incident direction is oblique then the shadow z
75. you should need more advanced scaling options please use the MScale option Coordinate manipulations the M family Advanced coordinate manipulation can be carried out using matrix manipulation The coordinate manipulation functions which is essential to the use of hybrid statements Box Cylinder etc is implemented as the following functions MTranslate lt TranslateX gt lt TranslateY gt lt TranslateZ gt MRotateX lt Rotation angle gt MRotateY lt Rotation angle gt MRotateZ lt Rotation angle gt MScale lt ScaleX gt lt ScaleY gt lt ScaleZ gt MPop MReset The manipulations carried out by the M family are cumulative This means that you can specify more than one operation to be carried out e g first rotate 90 around the Z axis then rotate 90 around the Y axis and finally translate 10 metres upwards The following example Shows these operations carried out on a cylinder shell the Cylinder statement is described later Manipulating a cylinder Par HAH MRotateZ 90 MRotateY 90 MTranslate 0 0 10 Cylinder 1 20 5 180 10 TB Cylindrical ceiling HHH The transformation commands to be carried out must always be stated before the points geometry on which they should work is created To reset all previous coordinate manipulations use the MReset command To reset cancel the most resent manipulation MTranslate in the example above use the MPop command which will pop the operation of the matrix stack 12 158
76. zipped file for efficient and safe storage or for easy posting by e mail available from the Files menu item Tools for detecting errors in a new model e g warped or overlapping surfaces available from the Toolbar dropdown menu Setup for printouts available from the options Program Setup Menu item Export of calculated data in ASCII text format for use in a spreadsheet or other post processing 2 29 2 2 Short guided tour Industrial edition Run the ODEON application You will find the ODEON program at the windows Menu Start Program files ODEON ODEON Execute the program and begin the tour Slopen a room model to work on Select the Open a room mode button to select a room The room files containing the geometries for ODEON carry the extension par or sur for compatibility with previous versions of ODEON and is plain ASCII text files following the format outlined in chapter 0 For this guided tour select the room model named eExample par EF DView Have a look at the room Whenever ODEON loads a room it is displayed in a 3Dview This allows you to investigate the geometry and check it for errors etc Several facilities are available in the 3pview e g rotation zooming highlighting of selected surfaces and corner numbers etc Press F1 to get overview of the facilities and their use Having assigned a room this is a good time to get familiar with the MDI concept Multiple Documents Interface At this point the t
77. 1 2009 The Inter Aural Cross Correlation is expressed as a coefficient from O to 1 First the normalized inter aural cross correlation function is calculated P O p t ade IACF 4 r dtl p Od ty t where p t is the impulse response at the entrance to the left ear canal p t is the impulse response at the entrance to the right ear canal Then the inter aural cross correlation coefficient is calculated as IACC max IACF for Ims lt r lt 1ms 7 89 STI Speech Transmission Index Speech Transmission Index known as STI is calculated according to IEC 60268 16 2003 The STI parameter takes into account the background noise which may be adjusted from the Room Setup For the STI parameter to be valid it is very important to adjust the background noise accordingly remember that background noise must be set in a relative level if relative source gains are used It should be mentioned that it is not stated in IEC 60268 16 2003 what kind of directivity the source in the STI measuring system should have so if using a source with directivity different from the one used in the real measurements in the simulations results may not be comparable The subjective scale of STI is given below Subjective scale STI value Bad 0 00 0 30 0 30 0 45 0 45 0 60 0 60 0 75 Excellent 0 75 1 00 In the point response and multi point response results five different speech transmission indexes are
78. 1Resid0deg hrtf doesn t have an ear canal therefore an ee filter should be used whereas the Kemar hrtf does have an ear canal so the ec filters should be used If the corresponding filter for the headphone used is not available then a generic filter matching the set of HRTF s may be used e g Subject_021Res10deg_diffuse hph If a diffuse field filter equalization is selected the results are filtered in order to obtain an overall flat frequency response of the HRTF s that is the average frequency response of all the HRTF filters is calculated and the auralisation results are filtered with the inverse of that If using headphones which are diffuse field equalized most headphones attempt to be and a matching headphone filter is not available then the matching diffuse filter headphone filter can be used For your convenience two directories with matching HRTF s and headphone filters are installed with ODEON namely the HeadsAndPhones EE and HeadsAndPhones Ec directories The first directory contains a set of HRTF s which was measured on a live subject with blocked ear canal by the CIPIC Interface Laboratory Algazi 2001 along with our matching ee hph headphone filters The later contains the well known Kemar HRTF s which includes ear canals along with our matching ec hph filters One of the directories can be selected in the oOptions Program setup Auralisation setup dialog once this is done matching HRTF s and headphone filters c
79. 2 159 LayerStatementRoom Par HH const L 40 const W 30 const H 3 const NumColX 4 const NumColY 3 const ColumnW 0 3 MTranslate 1 2 00 Layer Walls 1 000 0 502 0 000 orange colour Box I lw h tb walls in the room MPop modelling the columns for ColYCnt I NumColY for ColXCnt 1 NumColX MReset MTranslate ColXCnt L NumColX 1 w 2 ColYCnt W NumColY 1 0 NumbOffSet Auto Layer Columns 0 502 0 502 0 000 Box I ColumnW ColumnW h n columns in the room olive colour NumbOffSet Auto MTranslate 0 0 1 2 Layer Table plates 0 000 0 502 1 000 bluish colour Box 1 3 3 0 1 tb tables end end HHH Symmetric modelling Symmetric rooms can be modelled taking advantage of the ODEON convention for symmetric models This allows generation of symmetric or semi symmetric rooms with symmetry around the XZ plane Y 0 symmetric modelling is always carried out in the main coordinate system it does not take into account manipulations carried out using UCS MTranslate etc Modelling a surface symmetric around the main axis e g a reflector above the stage can be done using symmetric points Modelling left and right walls at the same time can be done using a symmetric double surface Symmetric points Surfaces symmetric around the XZ plane Y O can be made using symmetric points If defining the point Pt 2 1 0 1 0 1 0 in the geometry file using the point 2 in a surface definition of the geometry file will refer to the auto gen
80. 2D entities paragraph BLOCK s are not supported ODEON can not import entities which were inserted into a drawing aS BLOCK s Any BLOCK in a drawing which contains relevant 3D surface data must be exploded using the EXPLODE command before exported to the DXF file ODEON will notify the user if the pxr file imported did indeed contain BLOCk s 3D surface entities supported by ODEON e 3DFACE e Poly meshes MESH WEDGE PYRAMID BOX CONE CYLINDER SPHERE DISH DOME TORUS EDGESURF RULESURF and any other entities based on poly meshes e Poly faces the PFACE entity and any entity based on poly faces 212D entities supported by ODEON LINE POLYLINE CIRCLE ODEON can import LINE POLYLINE ARC and CIRCLE entities so called 2 2D entities when the elevation height is set to a value different from zero using the ELEV command in the CAD program Using the ELEv command at least this is true in IntelliCAD and AutoCAD makes it possible to convert parts of a flat line drawing into a 3D drawing typically a 2D floor plan can be converted into a set of vertical walls Use the CHANGE command in order to change elevation and height of these entities from within the CAD program 3DPOLY As an option it is possible to import 3ppoLy 3D polylines as if they were surfaces when these lines are closed polygons When ODEON exports surfaces containing more than four points these surfaces are exported as 3pDPOLy lines 3DPoLy lines will not respond
81. 3 6 We will get back to the receivers and sources under the topic Calculating Point Responses Assign material properties Open the Materials List and see how to operate it in the Materials menu Assign the following material data to the surfaces in the model Surface 2002 2003 number 2002 2003 4042 4042 4042 0 05 Hit the Fi shortcut to learn more about scattering coefficients and other material specifications EA Quick Estimate fast estimation of Reverberation Time From within the materials List run the Quick Estimate to get an idea of the order of the size of the reverberation time Note the longest reverberation time This calculation is very useful while assigning materials for the evaluation of different materials and their impact on the overall reverberation time Before leaving the Material list you May want to try this out by selecting different materials It is also possible to select among the defined sources However the source position will only have minimal effect on the estimated reverberation time unless strong decoupling effects are present in the room A Room setup calculation parameters At this point you should have an idea of the order of size of the reverberation time To continue the series of calculations you should enter the Room setup and specify the Impulse response length The Impulse response length Should cover at least 2 3 of the reverberation curve in this case 2000 ms should be sufficien
82. At this point you have tried the basic functions in ODEON and may want to view results for more realistic rooms In the room directory you will find pre calculated results in the rooms Elmia RoundRobin2 detailed par and PTB_Studio open curtains detailed model par which were the rooms used as test objects in the 2 and 3 Round Robins Bork 2000 Bork 2005 Geometry absorption data source and receiver positions as well as the measured room acoustical parameters are those supplied to all participants in the Round Robins by the PTB in Germany these data are publicly available at www ptb de To compare results D Ses NS A a m PSR SS X T l Ss ee see Een lt KIF a DRASS 3 A Zi yp be K L A KA lt lt A PAIPA A ARAA GIAA N C4 SS ans BAA AN CE lt Odeon 1985 2005 Another example Studstrup par is also available this is a model of a turbine hall at a power plant measured SPL A is included in that example This example is only available for the Industrial and Combined editions If you wish to carry out faster calculations you may enter the Room setup and select the Engineering setting this will provide results approximately 2 times faster without much loss in quality in results 2 37 AE NS AANI ba i Si x J da j 4 A Y i a d TACI j Wh a Ii f f A y TE u r H y N a7 3 ay
83. DAT recorder you Should use a wave file recording software in connection with your soundcard in order to transform the recordings into wave files Most soundcards comes with a software program for recording and editing wave files which should be capable of this job Please note that the connection between the CD ROM drive and you soundcard is often an analogue one so if you record from this drive you ll not benefit from digital inputs on your soundcard resulting in a loss in quality Output signals The output signals from all binaural auralisation are stored in two channel wave files and will have the same leading name as the room The result files being in the wave format makes it easy to edit and publish the results e g on the Internet or on audio CD s The binaural impulse responses files have the extension Jnn wav where nn refers to the relevant job number The wave files created as results from the convolve BRIR and Signal file table will have the extension ConvAurainn Wwav Where nn refers to the row in the table conv no The wave files created as results from the mix convolved wave results into one wave file table will have the extension MixAuralnn wav where nn refers to the row number in the table mix No The output from surround auralisation follows rules similar to those of the binaural ones the impulse responses are stored in wave files following the WaveFormatExtensible format where a signal is available for each lo
84. Dome2 Loop statements For End Transformation statements Mreset MPop MScale MTranslate MRotateX MRotateY MRotateZ and for compatibility with earlier releases of ODEON Scale UCS Predefined constants PI 3 14159265358979312 Predefined variables NumbOffSet ONVert Predefined Counters PtCounter Coordinate system definition statements Unit CoordSys Debugging Facilities DebugIsOn Debug Line folding markers Line folding is a feature of the ODEON editor where a section of lines e g a part of the geometry can be collapsed folded into one line in the editor for a better overview This is the only functionality of the two keywords BlockBegin BlockEnd they are ignored by ODEON when a par file is loaded The keywords are automatically generated when a room is generated by ODEONExtrusionModeller Or when a room is imported in the axf format BeginBlock lt optional comment gt NumbOffSet 100 Pt 1 0 1 0 Pt 2 0 1 0 Pt 3 1 1 0 Pt 4 1 1 0 Surf 1 A surface 1 2 3 EndBlock lt optional comment gt Any code between a matching set of BlockBegin and BlockEnd s can be collopsed by clicking a small in the left side of the editor making it easier to handle large files in particular with many layers All blocks can be collapsed from the view menu in the opEONEaditor And Blocks can be nested that is contain Blocks within Blocks Defining constants Constants must follow the syntax Const lt Name gt lt V
85. Far field balloon tab in the Odeon Array Source Editor 12 137 SPL Lin 500 Hz 16 OdenaniO1G85 32009 lireanced ta Cdenn AMS Figur E4 The Quadropol directivity pattern viewed in the 3D_Direct display at 500 Hz Because the distances between the transducers are 1 metre the Quadropol pattern has broken Viewing the sample files in ODEON The XML files are text files and can be viewed in a text editor such aS ODEONEdit Because the sample files follow the format outlined in this description they may also be viewed in the ODEON Array Source Editor It is described how to view the files from within the Array Source Editor in the Testing if XML files section below Having loaded one of the files into the Array Source Editor the Near field balloon Far field balloon and a 3D_Direct display can be studied Note that these directivity patterns are strongly frequency dependent and have pronounced symmetry properties At high frequencies their patterns break down and show strong fluctuations see figure E4 and viewing an down at 500 Hz Octopol in the Near field balloon display May not prove interesting because it will never radiate any energy in its symmetry planes which is what is displayed in this window horizontal or vertical as selected on the other hand the Quadropol in figure E5 gives a meaningful display tA b 10 00 metres front 5 7 2 8 11 3 19 8 28 4 35 9 45 4
86. Licensed to Odeon A S Hime ee cones Fig 12 3 Raw decay curve of a typical Impulse response with a well defined noise floor at the end of the impulse response ODEON calculates the truncation time for each octave band individually In this example the 1000 Hz filtered response is shown 12 120 C Odeoni2Combined Measurements Elmia RoundRobin2 detailed ImpRespFileO wav Raw decay curve at 1000Hz Jv E Measured v Noise floor Onset time Truncation time SPL dB 0 0 1 0 2 0 3 0 4 05 0 6 0 7 0 8 0 9 1 1 1 1 2 1 3 1 4 1 5 1 6 17 1 8 1 9 Odeon 1985 2013 Licensed to Odeon Ume seconds Fig 12 4 Impulsive noise has been present when the impulse response was measured If Signal to noise ratio is insufficient to derive all room acoustics parameters or if you are suspicious that there may be strong hills or spikes polluting the impulse response then try to repeat the measurement under more quiet conditions with an output gain or with a longer sweep length Series of impulse responses Fig 12 5 shows the raw decay curve for an impulse response recording containing 4 hand claps in a row Only one of the impulse responses has to be processed ODEON detects the one that has the highest peak in the broadband version i e the 2 one The beginning of the 3 impulse response defines the end of the noisy tail for the 2 one so that the truncation point is correctly placed with respect to the noise floor associated wit
87. Pt 12 L W 2 H Surf 1 floor 1 2 2 1 Surf 2 ceiling 11 12 12 11 Surf 3 end wall 1 11 11 1 Surf 4 end wall 2 12 Mirror Mirror works just as well defines point 12 and 2 Surf 5 side wall 1 2 12 11 HHH Below the box shaped room is modelled using the Box statement which is the easiest way to create this simple geometry A MTranslate statement is used to insert the Box at the same position as in the three other examples Parametric sample BoxStatement Par HHH const L6 const W 4 const H 2 7 MTranslate 1 2 0 0 Box Ilwh tb Walls and floor HHH Modeling a cylinder This example shows two different ways to create a cylindrical room with a floor and a ceiling In the first example the room is modelled using the Cylinder statement Parametric Sample CylinderStatement Par HHH const N 16 const R 15 const H 10 Cylinder 1000 N R 360 H TB Cylindrical room HHH The Cylinder statement is of course the easiest way to model a cylinder however sometimes more flexibility is needed e g different radius in top and bottom In the second example the corners in the room are modelled using the CountPt statement and the cylindrical surfaces are modelled using the RevSurf statement Notice that the number of points created by the CountPt statement is one higher than the number of sections in the RevSurf statement The bottom and top of the room is modelled using the Surf statement notice that points used by these surfaces are
88. UCS command must follow the syntax UCS lt TranslateX gt lt Translate Y gt lt TranslateZ gt lt RotateZ gt The VCS command is used to create a User Coordinate System with its own X Y and Z translation It also allows a rotation around the Z axis specified in degrees All point definitions made after a UCS call will be created in the specified coordinate system The default coordinate system is defined as UCS I I I 0 12 157 The UCS command corresponds to MReset MTranslate lt TranslateX gt lt TranslateY gt lt TranslateZ gt MrotateZ lt RotateZ gt If the UCS command doesn t fulfil your needs for coordinate manipulation you may use the matrix manipulation family MTranslate MRotateX MRotateY MRotateZ MScale MPop and MReset Scale The Scale command is mostly there for compatibility with previous versions of ODEON the coordinate manipulation functions MTranslate MRotateX MRotateY MRotateZ MScale MPop and MReset included from version 4 21 allow far more flexibility For your own sanity it is not adviceable to mix the Scale method with the M family method The Scale command must follow the syntaks Scale lt ScaleX gt lt ScaleY gt lt ScaleZ gt The scale command will multiply scale all the points generated after the scale call using the specified x y and z scale The default setting is Scale 1 1 1 The Scale command evokes scaling of coordinates after all other coordinate manipulation is carried out If
89. a low resolution display not all of the display may be visible however you can drag the borders between and inside the tables using the mouse Select the mix No 1 in the Mix Convolved wave results into one wave file table The rightmost table displays the binaural results that are combined in this Mix Select row 1 in the table and select Conv No 2 the simulation of the playback of the left signal then select conv No 3 in row 2 the simulation of the playback of the right signal Notice that you may also apply attenuation and a delay to each of the signals in the rightmost table of the mixer The attenuation corresponds to the attenuation knob on a mixer The delay is used for delaying the appropriate Convolved signal and should not be confused with a source delay An example where the delay feature could be useful is a simulation of an underground station where one signal is the train noise and another is the loudspeaker announcement the signals are not necessary of the same length and you may want to delay one of the signals You may also use the delay if you wish to make noise sources which are playing the same noise signals less correlated e g if ten sources are playing the same cocktail party noise ten Single Point response Jobs and ten convolutions apply delays like O 2 3 5 7 11 13 17 19 seconds or another time unit You may mix up to 25 convolutions together Calculating BRIR s left signal right signal and th
90. ably the most powerful way of creating 3D surface models allowing the use of commands such as UNION SUBTRACT INTERSECT SLICE INTERFERE etc and with a few steps it may be possible to convert these entities into something which is understood by ODEON IN Cadopia IntelliCAD Professional the 3DCONVERT command will convert above mentioned entities into entities recognized by ODEON Poly faces It is recommended to perform this operation on a copy of the CAD file rather on your original IN 3DStudioMax Select all the entities in the drawing using the cti A shortcut then right click the mouse on the drawing and select the Convert tolPolyfaees other options may also work It is recommended to perform this operation on a copy of the CAD file rather on your original 3 52 In AutoCAD 2000 the conversion process involves exporting to a 3ds file and re importing the exported file e Export the geometry into a 3D Studio file using the 3psoutT command this does not change your current CAD drawing e Import the 3DSwdio file just created back into a new clean drawing in AutoCAD using the 3DSIN Command In this new drawing the above entities has been converted to Polyface entities which are supported directly by ODEON At the same time all entities contained in BLOCK s have been exploded making them appear explicit thus directly compatible with ODEON Do note that the 3DSIN and 3DSoUT commands may not be available resent versions of AutoCAD
91. aining correct relative levels e g for comparisons between different seats in a concert hall In this case you should remember to use the same recording level convolver level and mixer level in the samples to be compared it is a good idea to use the same input Signal file to make sure that levels are the same at this point If you wish to compare across different rooms you should also be careful to remember that source gains in the rooms corresponds If using the streaming convolution Option available from the main display in the Joblis ODEON will maximize the auralisation output level so if you wish to compare different setups you should make sure to set the Gainin the Streaming convolution display to the same value Absolute play back levels for headphone auralisation Setting the level to an absolute level so the subject presented to the auralisation sample experiences the same level as would have been the case in the real room is a bit tricky as it involves every part in the signal chain To obtain a reasonable correct level a first approach is to adjust the auralisation output against levels of some kind of sound in the room in which you are e g if you are simulating voice try to compare the level of the playback with the level of somebody speaking in your room This method should make it possible to make a rough adjustment and it s certainly better than none A more precise method is to use the calculated SPL as a reference if it i
92. al slight warps of surfaces in the leaky region of the room which then have to be reduced as far as possible by revisions to the geometry file e Use the 3Dview Or 3DOpenGL for inspection of the model to study the region s under Suspicion It may turn out that a surface is missing or does not join to its neighbours in the expected manner It may help to zoom regions in question with the Highlight surfaces Show corner numbers and coords ANd Modelling options Switched on 3 58 3 59 4 Materials This chapter covers material properties and the facilities available from within the materials List The material list consists of a window containing two lists the surface list and the material library When selecting a surface in the surface list the surface is automatically highlighted in the corresponding 3D Materials window The Material list window consists of two parts e Surface List left part of the window e Material Library right part of the window 4 1 Material Library Right side of Material List window In the material database every 1000 numbers have a category e g gypsum or wood In each category the first 100 materials should be reference materials within the category ODEON has suggested a few to begin with Hereafter there will be room for 9 different manufactures lists e g with number 1100 1199 In this way the consultant decide which manufacturer should be having what 100 numbers of absorption by writing the
93. al time auralisation Select job number 5 in the job List and click the Streaming convolution Dutton This will open the Streaming convolution dialog Select your stereo input file in the Source signal field The convolver will begin to convolve a mono version of the input signal with the BRIR which was calculated for job number 5 To obtain stereo auralisation select BRIR number 6 as the Secondary BRIR for 2 channel auralisation ODEON will begin convolving the left channel of the input signal through BRIR number 5 and the right channel of the input signal through BRIR number 6 the result being a stereo playback in our simulated room The process involves four convolutions in parallel mixing binaural signals level adjustment and much more luckily this is all taken care of by ODEON To learn more about Streaming convolution please press Fi from within that 2 22 display Please notice that ODEON allow the combination of BRIR 5 and 6 because the same Single Point response receiver ANd Receiver pointing towards source are used in both simulations after all the Same person receiver can not sit at more than one place and have more than one head orientation simultaneously Ed Offline convolution The offline convolution more or less repeats what you have tried with the real time convolver the difference being greater flexibility more channels allowed individual adjustment of each channel delay and level is allowed plus auralisation results
94. all the necessary information on receiver position and orientations source s position s and orientations room geometry surface materials and the listener s geometry described by the HRTFs Convolving the left channel of the BRIR and the right channel of the BRIR with a mono signal a binaural signal is created which when presented to the listener over headphones gives the impression of the three dimensional acoustics at a particular position in the room It is also possible to simulate the recording of the BRIR s which is what ODEON does 12 131 HRTF s Head Related Transfer Functions In short terms the HRTF describes how an impulse arriving at a person dummy head is smeared out by diffraction phenomena from head and torso of the person While an incoming impulse is only 1 sample long this will result in an impulse response arriving at the right and an impulse response arriving at the left ear which may typically have a length of interest of some 2 3 milliseconds approximately 100 samples at a 44100 Hz sample rate or if you prefer a length of 1 metre or so this is what is described by the HRTF s A set of HRTF s used for auralisation will typically contain a library for many different angles of incidence The HRTF s that comes with ODEON are those made available by Bill Gardner and Keith Martin at MIT Media Lab at http sound media mit edu KEMAR html aS well as those from the CIPIC Interface Laboratory at http inte
95. alue gt where value is a mathematical expression which may be based on numbers or constants and variables that has already been defined Example 1 12 147 Const CeilingHeight 3 4 Example 2 Const FloorLevel 1 Const CeilingHeight FloorLevel 3 Example 3 Const FloorHeight 1 Const Length 6 Const CeilingHeight FloorLevel Length TanD 30 Defining and reassigning variables The definition of variables must follow the syntax Var lt Name gt lt OptionalValue gt Example 1 defining the variable FloorLevel Var FloorLevel Example 2 defining the variable FloorLevel and assigning the initial value 0 Var FloorLevel 0 Example 3 reassigning a variable adding 1 metre to the FloorLevel FloorLevel FloorLevel 1 Remark The predefined variable NumbOffSet may be used like any other variable but has a special meaning because it offsets point and surface numbering This variable is useful if copying a part of a geometry from another geometry file it is also useful in connection with the for end statements Auto can also be assigned to NumbOffSet in doing so ODEON will automatically increment the value of NumbOffSet to be greater than any point and surface number previously defined This has the advantage that repeated point and surface numbers can easily be avoided without having to keep track on the numbers used the drawback is that slight changes in the geometry file may change numbers on many subsequent surfaces ruining the
96. ample above The geometry displayed in the 3DView appears to be too small or large after re import If the geometry was initially imported using an incorrect unit then ODEON has defined its default view list in the 3DView in order to display that initial version of the geometry correctly To reset the view list use the ctrl DEL Shortcut from within the 3Dview 3 4 Model check in ODEON The geometry file is the first file used by ODEON when assigning a file from FilesiOpen Room model When assigning a new or modified room its validity is checked The check performed by ODEON involves checking whether data is consistent and in the correct format but not whether a meaningful geometry is being defined If the geometry 3 55 passes then you may start checking if the geometry is meaningful and without errors This may involve Viewing the room in a 3DView Viewing the room in the 3D0penGL display Analysing the geometry for unacceptable surface warps in the 3DGeometry Debugger Analysing the geometry for unacceptable surface overlap in the 3DGeometry Debugger Checking for missing surfaces in the room forming holes in the geometry The Unique edge s function available from the 3Dview may help you shortcut e Testing water tightness of the room tracing rays in the 3D Investigate Rays OF 3D Billiard window viewing the room in a 3DView The 3DView displaying your room once loaded into ODEON has a large number of facilities which
97. an be selected in the same dialog as well as in the Auralisation setup Specific to the individual room If installing new HRTF s or installing some of the additional CIPIC data which can be downloaded from http www odeon dk HRTF headphone filters are acceptable in the wav format In that case the filters should contain the impulse response s of the headphone as measured on a dummy head of the same type as the one selected in the HRTF drop down menu i e with or without ear canal or a corresponding ear coupler The filter may be one or two channels two channels are desirable if compensating a specific headphone that particular headphone rather than that particular model of headphone A measuring program such as DIRAC Dirac may be suitable for the measurement of the impulse response of a headphone The creation of the inverse filter to be used is taken care of by ODEON Adjusting levels Sound Pressure Level is one of the most important room acoustical parameters so it is important that levels at which auralisation samples are presented are realistic If playing a Simulation of voice at an unrealistic high level the speech intelligibility may be over rated it does not help that Clarity or Speech Transmission Index is satisfactory if the Sound Pressure Level is too low If play back levels are too high echo problems may be exaggerated because echoes that would be below audible threshold or at least at a very low level are made audible
98. and that the plug ins mentioned in the beginning of chapter 3 3 may not run on versions of Windows later than XP In this case the geometry has to be modelled without the use of the asic solid modelling entities or the files have to be exported using a program such aS Cadopia If ODEON reports of any of the unsupported entities when the dxf file has been imported this is because some 3D data is available in the pxr file in a format which cannot be converted by ODEON Consider following the steps above in order to create a dxf file which can be converted by ODEON Do note that acts solid modelling extensions may not be available in all editions of the various modelling programs Using LAYER s in the CAD drawing Surfaces will when imported to ODEON carry the name of the layer on which they were drawn Use the layer name to give the different parts of the geometry different names e g draw the Stage floor surfaces on a layer named Stage floor the sidewalls on a layer named Sidewalls etc If you are modelling subdivided surfaces such as Upper wall and Lower wall because you wish to be able to assign different materials to these parts of a surface it is advisable to model these parts on different layers in order to avoid that ODEON glues these surfaces together described below If a drawing is subdivided into layers this also makes it easier to assign materials to the surfaces in the Material List in ODEON because materials can be assigned
99. any point source from within ODEON To translate the created text file into an ODEON directivity file Select ToolsiCreate directivity So8 from ASCII file DAT Open the input file you have created Specify the name of the directivity file pattern you wish to create Select whether you wish a Calibrated source or not Apply calibration data as prompted for Applying Calibration Creating a new directivity file you will be prompted whether to create a calibrated source or not Calibrated source Sound Power Level O dB re 10E 12 W at 1 kHz YES NO Calibrated Sources Press YES if a generic source with an adjustable level is needed for ODEON calculations an example on this could be the omni or semi directional directivity pattern When selecting a calibrated source no data apart from the ASCII input file are required The directivity represented by the text file is preserved but the values are simply shifted by a constant amount the same for all bands such that the sound power level of the source is 0 dB re 10 12 Watts at 1 kHz Please do note that the power in the other bands may differ from 0 dB You may still alter the overall power response of the source by applying an EQ however the power at 1 kHz will always end up as O dB the other bands shifted accordingly NON calibrated sources Electro acoustical sources machinery natural sources etc Press No to preserve the sensitivity of an electro acoustical source or
100. are not recommended Programs such as AutoCAD 2002 IntelliCAD 6 Profesional Pro ANd 3DStudiomax are true 3D modelling programs and have been reported to be suited for the purpose Other programs may work as well but in any case you may have to experiment in order to find the optimum way to export and import the geometries from the programs About CAD drawings Room models to be used by ODEON must be surface models defined from plane surfaces no matter if the models are created in a CAD program or if they are modelled in the ODEON environment e g using the ODEON par format Once a model has been successfully imported by ODEON it is important to perform a thorough check geometries which look fine in the drawing program may still contain serious errors such as repeated misplaced or missing Surfaces CAD entities supported by ODEON Irrelevant drawing entities which are not supported Many CAD drawings are in fact 2D paper drawings rather than 3D models Such drawings do not contain sufficient information to create a 3D surface model and are ignored in the import process Examples of drawing entities which are ignored are circles dimensioning lines texts 3 51 etc 2D drawing data may coexist peacefully in a drawing containing useful 3D data the 2D data are as stated simply ignored It is possible to convert a few 2D entities into model data useful for ODEON provided that it is done from within the CAD program se the 2
101. are played first The energy in a room of low frequency sound usually takes more time to decay than the energy of high frequency sound Therefore upward sweeps are preferable over downward ones in order to ensure that the decay of low frequencies is captured within the recording of the whole sweep response and harmonic distortion is suppressed An extra decay period of a few seconds is recorded after the end of the sweep so that the remaining decay for middle and high frequencies is captured Octave Band Filtering The broadband impulse response obtained by the sweep method is filtered in octave bands between 63Hz and 8kHz using 2 order Butterworth filters according to the IEC 61260 1995 08 standard These analog Butterworth filters are implemented by digital infinite impulse response filters IIR filters which introduce unwanted transients in the beginning of the response 12 113 Although the length of the impulse response of the filters is infinite a finite effective length has been specified where 99 9 of the energy of the filtered response is included The length of the transients in the filtered response is taken equal to the effective length of the filter Moreover a reversed filtering is applied for decay analysis so that all the transients appear at the tail of the impulse response instead of the beginning and the filter phase distortion is suppressed ODEON automatically excludes this transient tail when processing the i
102. ase press Fi to consult the online help You may also select the page of interest and investigate the menu which appears at the top menu bar within the single point response window As a last option play the Binaural Room Impulse Response through headphones using the ctrit 1 keystroke Do note that a result cannot be viewed before it has been calculated ones a result has been calculated the relevant cell in the jJoblist will turn green in order to indicate that this result is available Calculate Multi point Activate the multi option from the Job list by checking the mutti option for job 4 then click the Run all Or Run Selected Job button When the calculation has finished select job number 4 in the Job list and click the view multi button to view the multi point response results To learn more about the results and options available from this display press Fi You may also select the page of interest and investigate the dropdown menu which as a response appears in the top of the program window Note that point responses calculated using the multi point response Option are calculated much faster than Single point responses because no filters are created for auralisation use gt Reflectograms are only used with point sources and will not contain any relevant information for line and surface sources If the Transition order is set to zero in the Room setup then the Reflectogram will at most contain one reflection the direct sound
103. at response Calculating reflections For calculation of acoustical parameters it is desirable that the true frequency content is included in the directivity pattern in order for example to correctly estimate SPL or Signal from anechoic recording with spectrum of SOLIFCe Calculating acoustical Ageing parameters STI However for auralisation the directivity e pattern should be equalised with the inverse spectrum of that recorded at the font axis of the natural source signal i e the wave file with human voice recorded with a microphone at the front axis SSS PNS Tra gt ODEON version 8 5 and later can manage to create correct estimates of parameters from natural sources and at the same time create correct auralisation where the overall spectrum is only included once But it is necessary to use a source marked natural ODEON is installed with some directivity patterns which have the word NATURAL attached to their names e g BB93_Normal_Natural Sos When natural directivity patterns are selected from within Point Source Editor a green natural label is displayed next to the equalization entry fields If having existing directivity patterns of natural sources which are not marked natural this can be done using the Tool Directivity patterns Mark So8 file as natural directivity When creating new directivity patterns this information is part of the input data Always use the _Natural versions of the directivity files
104. ate for that 12 3 Measurement set up In the Options Program setup Measurement setup important parameters can be adjusted concerning the measurement signal the post processing of an impulse response the calibration and your sound equipment Parameters for detection of onset time The Noise floor window length Specifies the time interval used to detect the noise floor before the onset time of the impulse response When a sound file contains more than one impulse responses in a row e g hand clap recordings in a sequence a sufficiently short Noise floor window length IS required in order for ODEON to successfully discriminate the different impulse responses In cases where magnetic feedback introduces strong spikes at the beginning of the impulse response this measurement error happens if microphone and loudspeaker cables lie parallel and close to each other for some distance this setting can help the user get rid of it Sweep model Two types of sweep signals can be used for a measurement in ODEON Linear sweep that has frequency energy spread equivalent to white noise and Exponential sweep which has frequency energy spread equivalent to pink noise In other words the exponential sweep provides longer playback time for low frequencies thus more energy at this range while the Linear sweep provide longer playback time at mid and high frequencies For most room acoustic measurements the Exponential sweep iS preferred against the Linear sw
105. ays assigned in order to benefit from the HAAS effect are mainly supposed to have effect in the time domain because loudspeakers are supposed to have significant distance between each other and multiple reflections will blur the effect in the frequency domain anyway e Delays assigned to the individual transducers in an array on the other hand are mainly Supposed to have an effect in the frequency domain the assumptions being that transducers are closely spaced and that signals are periodic Delaying a transducer means that a signal will be emitted later from that transducer than it would otherwise Example If transducer 1 is delayed by O ms and transducer 2 is delayed by 3 ms then at t 3 ms transducer 2 emits the same signal value as transducer 1 emitted at t 0 by having a delay the transducer looks back in time 11 3 Playing with level If the level is not the same for all the units in the array but if it increases gradually from bottom to top the beam of radiation becomes asymmetric An example is shown in fig 11 6 with a level increase of 2 dB per unit 11 110 27530 He Peps risitas Eke CIRP ra ES PISS epee ts 733380 Figure 11 6 The radiation in octave bands from 250 Hz to 8 kHz for a line array with 7 units The level increases by 2 dB per unit from bottom to top 11 4 Combining delay and level adjustments With the combination of delay and level adjustments it is p
106. bar dropdown menu You can operate the functions of the window using this menu or the shortcut keys displayed in the menu a Define sources and receivers Before any calculation can be carried out in ODEON one or more sources will have to be defined Of course a receiver will also have to be defined in order to calculate a point response In this guided tour we shall define a point a line and a surface source Finally we define a receiver Click the Source receiver list button at the toolbar to open the Source receiver list from which sources and discrete receivers are defined If the Source receiver list is already open but hidden behind other windows etc clicking this button will rearrange the windows as needed QDperine a point source Click the New point source Dutton in the local toolbar at the right side to open the Point source editor Enter the values x 3 metres y 2 metres and z 1 2 metres If you are not sure of the position of the source you can select the 3D Edit source display If you do so you should notice how the menu item 3D Edit Source appears on the dropdown menu when this window becomes active The 3D Edit Source Receiver Menu will allow you to operate the 3D display e g use the space key to switch between different predefined views Finally set the overall gain to 65 dB 65 is just an arbitrary value To save the new source just close the Point source Editor and confirm New sources are by default turn
107. been specified the import DxF file dialog appears allowing miscellaneous import options to be specified By default most of the parameters may be left untouched however it is important that the correct drawing unit is specified If the geometry does not appear as expected you may try other input parameters Unit in input file Unfortunately dxf files are unit less It is important that the correct unit in which the geometry was modelled is selected in the import dialog If the correct unit is not specified the import process may fail because the geometry seems to be only a few millimetres large or several kilometres in size Geometric rules glue surfaces Surfaces imported in the pxF format are put simple by nature surfaces build from three or four sets of coordinates When the glue option is turned on ODEON will try to glue or stitch if you prefer these surfaces in order to form fewer surfaces with larger areas Do note that some surfaces based on poly faces may not import correctly unless the glue option is turned ON and Don t allow subtractive PolyFace algorithm is turned OFF ODEON will not combine surfaces with each other when they are situated on different layers in the CAD drawing thus if you wish that certain surfaces are not glued together e g if upper and lower part of a wall should be assigned different materials either draw the surfaces on different layers in the CAD program preferable or turn off the glue surface s opt
108. bent array An example is shown in fig 11 3 and the coordinates and elevation angles of the units are shown in Table 11 1 below At high frequencies it is obviously a problem in this example that the sound radiation splits according to the number of units and there are gaps with poor sound radiation Table 11 1 Coordinates and elevation angles of the 7 units in the array example in fig 11 3 Transducer Elevation 0 000 0 000 0 000 0 000 0 000 0 000 0 000 11 108 11 2 Playing with delay One advantage of the line array is the possibility to control the direction of the main lobe of sound by means of small phase shifts different for each of the units So instead of physically tilting the loudspeaker the line array can be mounted in a vertical position and still direct the sound towards the audience If the units all have the same distance d and the delay from one unit to the next is At the angle of sound radiation relative to the normal direction perpendicular to the array line is 0 arag At d In fig 11 4 is shown an example with At 0 1 ms per unit and in fig 11 5 the same with At 0 2 ms per unit Note In order to turn the beam downwards the delays should be set from O ms in the upper unit to N 1 At ms in the lower unit e g 1 2 ms in the case of N 7 and At 0 2 ms 2D He Figure 11 4 The radiation in octave bands from 250 Hz to 8 kHz for a line array with 7 units and a time delay 0 1 ms per unit
109. c Ree eee ere Dene I Perera Sacursucune wees euiawe leer teases eMewee sees ean 0 0 1 0 2 0 3 0 4 0 5 0 6 0 7 0 8 0 9 1 1 1 1 2 1 3 Odeon 1985 2011 Licensed to Odeon A S UMS lt SECOnNdS Fig 12 9 Same impulse response as in Fig 12 7 The pulse due to the magnetic feedback has been cropped away by the user 12 124 Impulse response with distortion at the end Distortion at the end which appears as a hill of noise may have been caused due to presence of spikes in a measurement with the sweep method Deconvolution of a response taken with the sweep method tends to push the distortion caused by spikes to the end of the tail C Odeon12Combined Measurements BO_04 WAV Raw decay curve at 63Hz lv E Measured Noise floor Onset time Truncation time SPL dB 0 0 1 0 2 0 3 0 4 0 5 0 6 0 7 0 8 0 9 1 time seconds Odeon 1985 2011 Licensed to Odeon A S Fig 12 10 Impulse response with a prominent hill at the end Such a type of hill indicates that strong spikes were present during the measurement When using the Sweep method spikes in the recording are converted to hills after the deconvolution 12 125 Impulse response between buildings This is an example of measurement outdoors between several buildings In this case distant strong spikes at high frequencies indicate the presence of prominent echoes between the buildings At low frequencies the effect is less prominent In addition the reverb
110. cialist settings Below the General settings are the Specialist settings Which should only be adjusted if you are an ODEON expert or experimenting One exception is if you are importing rooms from earlier versions of ODEON then it will be a good idea to enable Screen diffraction to Make sure diffraction around screens is included in future calculations Impulse response details Max reflection order Job calculations only Max reflection order iS a Stop criterion which determines how many times a ray can be reflected Under normal conditions it should be as large as possible In that case the Impulse response length Will be the actual stop criterion and Max reflection order iS Only taken into account when stopping rays that has been trapped between two very narrow surfaces This number may be decreased if you are only interested in the very early reflections The Maximum allowed reflection order is 2000 8 93 Impulse response resolution Job calculations and Global Estimate The Impulse response resolution iS the width of the time steps in the Impulse response histogram in which the energy of the reflections are collected during a point response calculation The histogram is used for calculation of reverberation parameters such as EDT and Tx A resolution of approximately 3 ms is recommended Early reflections Transition Order Job calculations only The Transition order TO determines at which reflection order ODEON changes from the ear
111. compatible with the HRTF s supplied with ODEON the wave files should always be at a 44100 Hz sampling frequency The ODEON program comes with a few anechoic samples which are installed to the ODEON WaveSignals directory If you wish to extend the library of input signals you should put your new signal files here or in a subdirectory to this directory e g ODEON WaveSignals English voice or ODEON WaveSignals NoiseSignals A few audio CD s containing anechoic recordings are commercially available namely the Archimedes CD Music for Archimedes 1992 which contains some recordings of solo instruments and the Denon CD Anechoic Orchestral Music Recordings 1988 which contains semi anechoic stereo recordings of orchestral music The easiest way to transfer recordings on an audio CD into wave files on the hard disk on a computer is probably to use a software application known as a CD ripper This also ensures the transfer is without loss in quality Signals ripped from CD audio tracks will always be in two channels if you know that signals in fact are mono signals it will be a good idea to convert the resulting wave files into mono Signals this will save space on the hard disk and avoid confusion whether a signal is stereo or in fact mono A standard wave file editing software which is usually included with the soundcard should be capable of doing the job If you have recordings which you have created yourself e g using a
112. convolve it with the Clapping signal file an anechoic recording of hands being clapped which is eventually a less transient signal than an ideal impulse A note on directivity patterns for natural point sources With natural sources we refer to sources such as human voice an acoustical instrument or similar where a recorded signal for auralisation may be associated with the directivity pattern In order to select the right source for auralisation purpose please read chapter 10 Head Related Transfer Functions and digital filtering To create binaural simulations a set of HRTF s see Appendix B Vocabulary is needed The HRTF s are different from subject to subject and in principle you may measure your own ones and import those into ODEON using the Tools Create filtered HRTF Menu entry in the ODEON program Measuring HRTF s is however a complicated task so you will probably be using the Supplied ones If you should be interested in creating own sets of HRTF s for ODEON additional information can be found in the help available from within the ODEON program The imported HRTF s to use for auralisation are pre filtered into octave bands in order to reduce calculation time The octave band filter parameters for the selected filter bank can be seen on the filter bank name at the Auralisation Setup Menu The filter parameters are 5 66 M The M value is taken into account if the Apply enhancement option is Checked If the file name contains
113. cr houausuanucceeeecer te SSPE eae eee eee e eee edie eee eneeaeeeeaeeecanen eens den eaeesees MMB scenecueeeneaaDeceaecneaeaeeceencaecuseeendeaeeensecueneneaucteeseausaduereuceeucuenseousueeeauseQaccecuseetsuseeecauenseneaeeQens I Baie ue Kae RNRSS SSNS A EERE RSE RNS E Sm Era FIONN NRSR SESS MERE SEES CELE PREETI FERRI SEE REET SENET a EEE S ceri RRB SN RIN NE A T E PEE UNG EMER ENR NaS ERG E Reece Re TRESS MGS S ANT S N RICH CFSE EE cme rut SHRRRSS N T FERRE PSEEE Chasm acon Frere E ae rere rer rece ieneenneennree sare ce ere macsereene Sererre Preerpernenenncnenreerceccee 14 pr sesanserterecrecereernamonnernrrerceereererececnasaesecrerree arepeenosesocr preceeecre mseasscnecs ererr screen nencnnnnrnnrrcrereer heres sancreacey errerererr erry parerrnnn recrercce ree cnc ere E lessees meres tes COREE RERSECE a RRR CCE EERE 7 tended pecdedeucenceceenonnnales SPL dB s E errr Wallflr he eeararerrnrer 1 5 1 0 5 0 0 5 1 1 5 2 2 5 3 3 5 4 4 5 Odeon 1985 2011 Licensed to Odeon A S time seconds Fig 12 6 Recording of Fig 12 5 filtered at 125 Hz The impulse response at this octave band has very poor peak to noise ratio and its length is too short so that a truncation time is impossible to be derived Instead the estimated and of the response is displayed as an indication that the measurement is not trustful C Odeon12Combined Measurements IR_Basement_Long wav Raw decay curve broad band
114. ctogram Image sources are split into a specular contribution and a scattering tree which consists of secondary sources on the image source surfaces allowing a realistic calculation of early scattering The attenuation of one particular Image source is calculated taking the following into account e Directivity factor of the primary source in the relevant direction of radiation e Reflection coefficients of the walls involved in generating the image can be angle dependent if Angular absorption is enabled in the Room Setup e Air absorption due to the length of the reflection path e Distance damping due to the distance travelled from the primary source to the receiver e Scattering loss frequency dependent due to the scattered energy which is handled by a scattering tree Scattering may occur because of surface roughness as specified by the scattering coefficients in the materials list or due to limited surface dimensions or edge diffraction Early scattering In short each time ODEON detects an image source IMS an inner loop of scatter rays not visualised in the 3D Investigate Rays display is started taking care of the scattered sound which is reflected from this image source surface Example If all scattering coefficients in a room is 0 5 then the specular energy of a first order IMS is multiplied 1 0 5 and the specular energy of a second order IMS is multiplied by 1 0 5 1 0 5 The scattering rays handle the
115. currently possible options for real measurements Therefore you should uncheck the Measured option for any such parameters in the Define room acoustics parameters Audio devices All the audio devices installed in your PC should appear in this menu You should choose which devices you prefer to use for recording input device and which for playback output device Source power spectrum ODEON comes with two types of source power spectra that can be used with the calibration of the measuring system A flat frequency spectrum source called G Iso 3382 1 and a speech spectrum source called sSpeech ISO 3382 3 The source type G iso 3382 1 Should be chosen for almost all room acoustic cases covered in the ISO 3382 1 auditoria concert halls etc On the other hand source type Speech ISo 3382 3 Should be chosen if the measurement is or has been carried out in an open plan office ISO 3382 3 standard Apart from the default settings the user can define a custom source spectrum Background noise spectrum This specifies the absolute RMS dB value of the background noise in the room per octave band The values is obtained from the Room setup if a room has been assigned otherwise these values are used The level of the background noise is used in the calculation of the Speech Transmission Index and is important for the ISO 3382 3 results presented in the multi point response of ODEON Decay curve settings Here you can adjust the resolution of th
116. d as a part of the Multi Point response if the job only contains one active source the active source is a point source more than one receiver is defined and the distance between the source and the receivers are not the same for all receivers Please notice that one misplaced receiver may ruin the entire DL calculation thus it is a good idea to check the receiver positions or even better to check the individual results of the Multi Point calculation DL is given for the frequency bands 63 Hz to 8 kHz and DL2 co is the A weighted Rate of Spatial Decay for the frequency bands 125 Hz to 4 kHz For DL as well as DLz2co the correlation coefficients are calculated If the correlation coefficients are low this may indicate bad locations of source and or receivers however it may also indicate a very low damping in the room the Spatial Decay Curve being almost horizontal 7 90 The measuring points Receiver points and the source position are of course essential to the DL parameters and should follow ISO 14257 2001 As an example a path of receivers may be chosen in the following distances from the source using logarithmic increment 1 2 4 5 6 3 8 10 metres The positions should also follow the standard with respect to distance from floor and reflecting Surfaces ODEON will use all the receivers defined in the receiver list In some cases the positions of the receivers will not combine with the receiver positions that should be used for
117. d for such a case Impulse response with magnetic feedback When long cables are used in a measurement for the microphone as well as for the loudspeaker and the cables lie close to each other and parallel for some distance this can lead to magnetic feedback resulting in an early peak with virtually no delay arriving some time before the start of the impulse response is actually detected by the microphone Fig 12 7 This peak is undesirable and should be removed Changing the Noise floor window length can help in placing the truncation time at a correct place but the onset time will be still placed wrongly at the peak of the magnetic feedback Fig 12 8 The best solution is to zoom the healthy part of the impulse response then save this cropped version using the c shortcut as in Fig 12 9 It is of course better to avoid long parallel cables in the first place if you are still in the field then by all means repeat the measurement 12 122 C Odeon12Combined Measurements Clapping wav Raw decay curve at 125Hz O nnn pn ne er ene err a nine pp pnnnnnnnnt ereren er UP eeECCCCCCT See ener reer ners Baa CCCCCCCCCC BERRI ER CE DEE EEE rrp Enmnnnnnnnn Mercere ee eeeCCCCUT PRE Perr PAE E a aEE CCCCCCCaT Chaconne on erEeerrEErer cert perprnnnnracceeecceney Seen E Measured Foo an ga ear alae Estimated end of response ERCERSESREIN ace eS RE ane Ee Ce CC Pe CEREUS E E E E aececcedec CoCo aaa Op aE EnBRSE oedoo nu SUNS E E BER EREEREEEL
118. de of the software or the creation of derivative work based on ODEON software is strictly prohibited In no way may you transfer assign rent sublicenses lease sell or otherwise dispose of any portion of the software on a temporary or permanent basis TRANSFER RESTRICTIONS The ODEON software is licensed only to the licensee In no way may you transfer assign rent sublicenses lease sell or otherwise transfer any portion of the license on a temporary or permanent basis this includes transfer between branches of international companies that are 1 6 registered in different countries The license may only be transferred to anyone with the prior written consent of ODEON A S Any authorized transfer of the ODEON software shall be bound by the terms and conditions of this Agreement TERMINATION This license is effective until termination This license will terminate automatically without notice from ODEON A S if you fail to comply with any provision of this Agreement Upon termination you shall destroy the written materials and all copies of the ODEON software including archival copies if any NO LIABILITY FOR DAMAGES Neither Odeon A S nor anyone else who has been involved in the creation production distribution or delivery of this program shall be liable including without limitation damages for loss of profits business interruption loss of information incorrect results recovery of data or other pecuniary loss for any d
119. deally only the energy of the direct sound should remain after the truncation Unfortunately the truncation is quite approximate at low frequencies because the direct sound and the subsequent reflections overlap to each other due to the long wavelengths of the sound waves and the presence of phase shifts It is recommended that more than six source receiver combinations should be used for the free field calibration since it is very likely that the source does not produce a perfect omni directional pattern but a pattern full of lobes This means that in contrast to the diffuse field calibration the free field calibration is very sensitive to receiver positions around the source Similarly to the diffuse calibration you should select and load all impulse responses obtained for the same calibration at once so that ODEON will calibrate the level according to the average of the values Once a calibration has been performed it is important that any external level adjustment not set inside ODEON is set to same level during measurement as was the case during calibration This includes levels set for play back level if set to 100 it s easy to remember recording level if set to 100 it s easy to remember and microphone boost set inside Windows as well as gain factors set on external devices used in the measurements Or alternatively that the factors are corrected using the external adjustments Gain in the Program setup Measurement setup tO compens
120. diffuse field conditions and as such it is a more reliable method for estimation of global reverberation time e For workrooms where all absorption is often situated in the ceiling region and sources are situated in the floor region the RT predicted by Global Estimate will typically be longer than the values predicted by Quick Estimate a factor two is not unlikely if walls are basically smooth e In auditoriums the opposite is the case because the dominant absorption area the audience is close to the source 2 26 In any case the RT s predicted by Global Estimate is the most reliable provided that proper scattering coefficients have been entered The principle of the method was first suggested by Schroeder Schroeder 1970 e it Cay Point Response calculations The Point response Calculations estimate not only RT but also room acoustic parameters like Clarity Deutlichkeit English Definition SPL SPLa STI and LFg see chapter 7 The calculated results can be thought of as a simulated measurement Calculated results relates to e anumber of active sources e one receiver position e orientation of the receiver for LFg9 LGgox and auralisation The orientation of the receiver s in a particular job is set in the Job list by selecting a point source through which the receivers are looking This point source need not be active it may indeed be an inactive dummy source which is only used as an aiming point There are three k
121. directions in the set of HRTF s is kept neutral Sample rate The sample rate of the HRTF This sample rate should be the same as the sample rate of the Signal files anechoic recordings to be used The supplied HRTF s are sampled at 44100 Hz Apass Ripple of octave band filters in dB Smaller is better 0 5 dB is probably sufficient Astop Maximum possible attenuation of octave bands To allow complete attenuation of all reflections of a 16 bit signal 96 dB dynamic range Asx should be 96 dB however due to auditory masking we are not able to hear such differences so 40 dB is probably sufficient Smaller Asop leads to shorter calculation time of the BRIRs Band overlap in percent Octave bands implemented using FIR filters are not completely rectangular it takes some frequency span before they attenuates completely An overlap between the filters of 100 percent gives a smooth transition between the filters which is probably a more realistic representation of real world reflections than shorter overlaps At the same time long overlap gives shorter calculation time of the BRIRs If you should need to use filters with other filter parameters e g A being 96 dB you should create a filtered set of HRTF s with these parameters use the FilelCreate filtered HRTFs Option Then from within your room select the new filter bank from the Auralisation Setup If you should need to import other HRTF s than the kemar Gardner amp Martin
122. e Blue layer IX Blue FF Surface editor Surface Description Layer No description 1 Blue layer 5 00 ye No description 1 Blue layer 5 00 No description 1 Blue laye 5 00 lt No description 1 Blue layer 5 00 ii Om al EE E ze D gt No description 1Bluelayer 2 50 Mirror i Vert mirror at 0 000 Metres Vertical Horizontal Horiz Mirror at 0 000 Metres Point editor 1 00 Point x Z Extrusion Surface 3 3 0 000 2 8 000 0 000 3 16 000 2 000 16 000 6 000 X X X 0 00 42 00 44 00 g6 00 48 00 y 0 00 I 2 00 y 4 00 penn X 6 25 metres Z 9 00 metres Point input Locked Mouse Drag Selection Scroll RMB Zoom Alt LMB Select Point Ctrl LMB Move Point Ctrl Alt LMB Move Surface Shift LMB New point LMB Start the program a shortcut to the program is found at the windows Menu Start Programs ODEON ODEONExtrusionModeler Initial settings Before starting modelling geometry select the drawing plane X Y or Z which is best suited for the geometry to be modelled Also select properties for grid and snap spacing Using a drawing of the floor plan as the layout It is possible to load a 2D background drawing section plan as basis for the geometry in various image formats png jpg gif emf wmf and to use this drawing as the basis for the drawing To load a background drawing e Use the File Load backgound drawi
123. e but a certain amount of overlap and warp by default 50 mm is allowed without generating a warning By overlapping surfaces is meant surfaces which define a part of the Same plane in space In the simple case this can be because the surfaces are simply duplicates another case could be a door which has been defined in the same plane as the wall in which it is mounted Overlapping surfaces should be avoided because it will not be clear which absorption coefficient should be applied at a reflection in case of overlapping surfaces with different materials Warps can lead to holes in rooms at edges of joining surfaces with erroneous results as a consequence and the surfaces will not be well defined Using the 3DGeometry debugger in ODEON ODEON will generate a list of warnings and a corresponding illustration in a 3D display whenever an overlap or a warp exceeds the value specified in the Room setup Model Air conditions dialog 3 57 Overlapping surfaces is a tricky problem because it is usually invisible on 3D projections of the geometries however such errors in the model may lead to unpredictable results so always check models of some complexity for overlapping surfaces El Testing Water tightness using 3D Investigate Rays Testing a new model for water tightness i e whether it is completely closed may be done USING a 3D Investigate Rays Window The room model may not be watertight if Surfaces are missing from the model Sur
124. e data and polar plots Loudspeaker manufacturers can use the CLF format to supply data to end users of professional acoustic computer programs www cifgroup org CLF is defined in two parts a binary format for data distribution and a text based format used solely by the loudspeaker manufactures for data input and editing As a user of ODEON you should deal only with the binary distribution files having the extensions cri and cr2 In order to view all data in the CLF format you should download a free viewer from the CLF home page CF1 has a frequency resolution of 10 degrees 1 1 octave and crz has a frequency resolution of 5 degrees 1 3 octave If data are available in either format for a selected loudspeaker then the cr2 format should be preferred because of its angular resolution Currently ODEON does not make use of the higher frequency resolution of the crz format however in the future ODEON will make use of this extra information for calculation of the distance dependent directivity of loudspeaker arrays which are composed from multiple units which are added with phase The CLF Group is providing a set of free tools for data editing conversion from text to binary format and viewing binary data allowing loudspeaker manufacturers to create view and verify binary distribution files for use in ODEON This ensures that it is easy for loudspeaker manufactures to make these data available Links to loudspeaker manufacturers currently providin
125. e par extension e g Room par The par file contains geometry in the Parametric modelling language file format This format can be edited manually in the ODEON text editor see appendix E Google Sketchup Our current preferred program for room modeling is Sketchup SU su20deon is the ODEON plug in for SU that allows you to make direct use of SU models in ODEON SU is a 3D modelling software which is operated very intuitively It is available in a free as well as a pro version and can be downloaded at http www sketchup com download SU also allows you to create renderings of your rooms for impressive visualization To learn using Sketchup it is a must to watch some of the introduction videos which are found at http www sketchup com intl en training videos html In a day or so you should have learned the basics We have also created a few video on modelling for Odeon with SU at http www odeon dk tutorials acoustic simulation mod To make use of the SU models in ODEON the su20deon plug in must be installed It can be downloaded from http www Odeon dk Download The download includes installation instructions and last minute instructions Once you have installed SU and the plug in su20deon you can start creating models for ODEON using SU Just save the SU model in the ODEON room folder and press the ODEON icon in SU menu bar then suzopeon will create a par file which you can open directly in ODEON note that for large models the SU ap
126. e Directivity factor of the primary source in the relevant direction of radiation point sources only e Reflection coefficients of the walls involved in generating the image can be angle dependent if Angular absorption is enabled in the Room Setup e Air absorption due to the length of the reflection path e Distance damping due to the distance travelled from the primary source to the receiver is inherently included in the ray tracing process e Directivity factor for secondary sources e g the Lambert Oblique Lambert or Uniform directivity see later Summarizing the calculation method used for point response calculations in ODEON As described above the point response calculation in ODEON is divided into a receiver independent and a receiver dependent calculation part The division into two calculations is solely done in order to save calculation time by reusing parts of the calculation where possible One of the advantages of the late ray tracing method used in ODEON compared to more traditional methods is that rays do not even have to come near to the receiver to make a contribution and a late ray being reflected 100 times has a potential of generating 100 secondary sources Thus even in coupled rooms with only a modest number of rays it is possible to obtain a reasonably number of reflections at a receiver which is required to obtain a result that is statistically reliable This results in a fine balance between reliability of the calc
127. e Y axis pointing to the right as seen from the audience e Z axis pointing upwards The syntax is CoordSys lt X gt lt Y gt lt Z gt where X Y Z indicate which axis should be used as the x y and z axis inside ODEON X Y and Z may also have a sign to indicate that the axis should point in the opposite direction Example 1 the default orientation which is assumed by ODEON if the CoordSys statement is not used in the geometry file CoordSys X Y Z Example 2 changing the direction of the X axis CoordSys X Y Z Example 3 Swapping the X and the Z axis CoordSys Z Y X Example 4 The CoordSys statement may be used more than once in the same par file HHH CoordSys X Y Z se g if the X axis was inverted in imported model data sresetting the coordinate system to the default CoordSys X Y Z model data appended in the ODEON editor modelling environment sit is most practical if using the default Coordinate system when modelling in the ODEON environment then coordinate system will have the same orientation in the ODEON editor as well as in the 3DView inside ODEON HHH User coordinate system The UCS command is mostly there for compatibility with previous versions of ODEON the coordinate manipulation functions MTranslate MRotateX MRotateY MRotateZ MScale MPop and MReset included from version 4 21 allow far more flexibility For your own sanity it is not adviceable to mix the vcs method with the M family method The
128. e impulse response as it appears at the Decay curves display See Load Impulse Response Section When no room is assigned to ODEON the default setting for the resolution is 3 0 ms With a room assigned the value is taken directly from the Room setup SO that the measured energy response can be compared side by side to the simulated energy response obtained in the Single Point Response External adjustments The overall Gain for the sweep signal playback can be adjusted here 12 4 Examples of Impulse Responses A good measurement results relies on a healthy impulse response Although it is difficult to give a general definition on what a healthy impulse response is here is some guidelines that may help in obtaining acceptable results 1 Sufficient signal noise ratio at least in the octave bands of interest 12 119 2 A noise floor as flat as possible at the end of the response if the noise floor is included in the impulse response is a good indication that the impulse response is not polluted by impulsive noise 3 No presence of quantification artefacts due to poor recording resolution input level at recording of the impulse response should be high enough 4 Presence of spikes hills in the impulse response could indicate presence of impulsive noise during the measurement no matter if the impulse response was recorded directly or obtained using the sweep method implemented in ODEON If in doubt it is a good idea to make an extra measu
129. e source Editor and confirm a Surface source The facilities of the surface source are fully included in the multi surface source the surface source is only available for compatibility reasons Bbefine receivers Click the New receiver button to open the Receiver editor Enter the values x 1 5 metres y 0 5 metres and z 1 65 metres To save the new source just close the Receiver Editor and confirm Define other receivers at x y Z 12 3 2 2 x y Z 8 7 1 5 x y Z 21 1 3 6 We will get back to the receivers and the activated sources under the point Calculating Point Responses Assign material properties Open the Materials List and see how to operate in the Materials menu Assign the following material data to the surfaces in the model Surface 2002 2003 number 2002 2003 4042 4042 Hit the F1 shortcut to learn more about scattering coefficients and other material specifications Notice high scattering coefficients are used on the floor and sidewalls in order to model machinery and beams Quick Estimate fast estimation of Reverberation Time From within the materials list run the Quick Estimate to get an idea of the reverberation time Note the longest reverberation time This calculation is very useful while assigning materials for evaluating different materials and their impact on the reverberation time Before leaving the Quick Estimate YOU may want to try this out by choosing d
130. e stereo signal The stereo setup has now been completed and you may start calculations Run al Depending on the source gains you have chosen you may experience overload or under range in this case you should adjust the Recording Level Rca Lev and or Mixer level and recalculate These levels correspond to the levels on a tape recorder and on a mixer and the problems concerning overload and under range are the same If levels are too low you will get a poor dynamic range and if too high you will experience clipping The out Lev in the rightmost columns of the tables should not exceed O dB on the other hand if the output level is say 30 to 50 dB a very poor dynamic range is obtained Playing results When calculations have finished you may play the calculated binaural simulations Select the relevant table row and column then click the play button or the alt s short cut e To play the input signal select the signal file column in the Convolve BRIR and Signal file table e To play the mono signals convolved with a BRIR select any other column in the convolve BRIR and Signal file table e To play the mixed results select the relevant row in the mix table e Finally to play the individual components in a selected mix select the relevant row in the rightmost table mixer level adjustments are not taken into account These signals are just a repetition of the convolved results from the leftmost table gt The Out lev displays the level
131. eataseianaehsaniwseastessknbiwaantsaceaestedeenessiantaess 3 41 ae MANTOO aa EA A 3 42 Coode SKER NUD merri A EEE E E 3 42 ODEON Extrusion Modeller assssssnnssnnnnsnnnnsnnnnsnrnnsnrensnrenenrerrnnrrrnnrnrnnsnrnnenrenenrennn 3 44 3 5 IMporind DXF and SDS THES a a A 3 51 CAD entities supported by ODEON ccccccccces seen ener eeeeeeesseceenenennnneeeeeeesseeeeanennaannees 3 51 Performing the import in ODEON c ccc ceeceeee cece eee e eee eee e ee ee esse eeeeae eee eennnneeeeenaas 3 53 Editing the imported geometry cccseeeeceeceeeeeeeseeeeee seen nnn neeeeeeeeseeeeeanenananneenenesnges 3 54 3 4 Model check iN ODEON caccaasnanicaiasanecesnessuaninestesnenawesseeertasniaerinsneeertecsenaniaasias 3 55 Biiewing Ee OOM in a DVCW arieso eani aa eia a n E a NA 3 56 B25 COPING OCON ICS saarn E EE ET A E E E AT E 3 57 a 3DGeometry debugger cicaterancnndeuncteug Covauiiacenadniadaseiindmageen cating meniuadategsine meds 3 57 W testing Water tightness using 3D Investigate RAYS ccccceceseeeseeeeeeeeeseeeeeeeneeaes 3 58 4 Matera oerni E E AA NEE A EEA EE OE 4 60 4 1 Material Library Right side of Material List wWiNdOW ccccceeeeeeeeeeeeeeeeeeeeeeeeees 4 60 Peca ME aaa A E danas 4 60 Editing and extending the Material Library ssssssssssssssnnnnsrnnnsrrnnsrrnnsnrnrenrrrrnrsrene 4 61 4 2 Surface List Left side of Material List WINdGOW cccccceceeeeeeeeeeeeeeeeeeeeeeeeeeeeeees 4 61 4 3 Mana
132. ectangular area is magnified to fit the whole window Raw Decay Curve This is a display of the squared pressure impulse response i e energy impulse response together with the onset and truncation times In this graph the values of the squared pressure are in dB ref 20 uPa which makes details more visible Similarly to the Raw Impulse Response both the onset and truncation times are displayed In addition a horizontal solid blue line indicates the noise floor in the impulse response see Fig 12 2 When the noisy part of the response has a high degree of fluctuation this solid line becomes dashed indicating that the noise floor is far from being flat so that the estimation is not trustful Decay Curves On this display the pure part of the impulse response between the onset and truncation times is processed further Three types of curves are displayed in the graph for each octave band e E Measured This is the energy impulse response Raw Decay Curve between the onset and truncation times with a resolution specified either in the Room setup or the Measurement setup The display is fully compatible with the Decay curves displayed in the simulated Point responses in the Single Point display in ODEON auditorium and Combined e E Integrated This is the result of the backwards Schroeder s integration of the energy impulse response between the onset and truncation times e E Corrected This is the E Integrated curve with compensatio
133. ed If the Source receiver list is already open but hidden behind other windows etc clicking this button will rearrange the program windows as needed Define a point source Click the New point source Dutton in the local toolbar at the right side to open the Point source editor Enter the values x 3 metres y 2 metres and z 1 2 metres If you are not sure of the position of the source you can select the 3D Edit source display If you do so you should notice how the menu item 3D Edit Source appears on the dropdown menu when this window becomes active The 3D Edit Source Receiver Menu will allow you to operate the 3D display e g use the space key to switch between different predefined views Finally set the overall gain to 65 dB 65 is just an arbitrary value To save the new source just close the Point source Editor and confirm New sources are by default turned orf therefore it will not be visible in the 3p Edit source display Press the space key to activate the source for the current Job more on Jobs later on If you are running the Auditorium edition of ODEON define two extra point sources of your own choice and go to the paragraph Activate sources Otherwise if you are running the combined edition continue below defining a line and a multi surface source t Hint Use the Tab or Shift Tab keys to move between fields Depending on the language selected on your computer or is used as decimal point The deci
134. ed in the above tour ODEON also contains facilities for Measurement facilities for room acoustics simulations which is covered in Chapter 12 Calculation of transmission through walls this issue is covered in Appendix C Copying the project files generated by ODEON available from the File menu item Deleting calculation or result files available from the File menu item Archiving project files in one single compressed zipped file for efficient and safe storage or for easy posting by e mail available from the File menu item Tools for detecting errors in a new model e g warped or overlapping surfaces available from the Toolbar dropdown menu Setup for print outs and graphics available from the options Program Setup Menu item Export of calculated data in ASCII text format for use in a spreadsheet or other post processing 2 36 2 4 Pre calculated Rooms Round Robins Odeon 1985 2005 calculated by ODEON with those measured in the real rooms e Open the room in question e Open the Joblist the shift ctri 3 shortcut e Select one of the pre calculated Multi point response jobs job one or two in the Joblit and open it the atttm shortcut e Select the Measured versus simulated tab sheet in the mutti Point display A couple of other examples Hagia Irene par IS a model of a Byzantine church in Istanbul which like the examples above also includes the measured room acoustical parameters derph
135. ed into the USB port on the PC If you start the program without the hardware key it can only be used in viewer mode c When you have installed the ODEON software please check for the most resent updates at www odeon dk updates 1 2 Upgrading from previous versions If you are upgrading from previous versions of ODEON read on to learn about the changes in ODEON To learn about the revision history of ODEON please refer to the Help Contents Contents Whats new in Odeon 12 tab from within ODEON Below is a list of issues which you Should be aware of when upgrading from previous versions Upgrading to version 12 ODEON version 12 runs on Windows 7 32 as well as 64 bit editions Windows Vista 32 as well as 64 bit editions and Windows XP ODEON 12 is a major upgrade please see section 0 Though ODEON 12 is capable of loading and converting older projects into the version 12 format forward compatibility an older version of ODEON may not load a room once it has been loaded into ODEON 12 ODEON 12 includes a large number of enhancements for a fairly complete list see the help file from within the ODEON software press Fi from within ODEON then click Whats new in ODEON 12 entry in the contents menu Features introduced with version 10 ODEON 10 is Unicode and utf s enabled allowing text in complex character sets to be saved with your projects whether this is in the text files such as the geometry files par or texts composed in the var
136. ed orf therefore it will not be visible in the 3D Edit source display Press the space key to activate the source for the current Job more on Jobs later on Hint Use the Tab Or Shift Tab Shortcuts to move between data fields 2 befine receivers Click the New receiver Dutton to open the Receiver editor Enter the values x 1 5 metres y 0 5 metres and z 1 65 metres To save the new source just close the Receiver Editor and confirm Define other receivers at 8 Hint Use the Tab or shift Tab keys to move between fields Depending on the language selected on your computer or is used as decimal point The decimal separator to use internally in Odeon may also be selected from the options Program settings Other settings entry 2 34 x y Z 12 3 2 2 x Y z 8 7 1 5 x y z 21 1 3 6 We will get back to the receivers and the activated sources under the point Calculating Point Responses E assign material properties Open the materials List and see how to operate in the Materials menu Assign the following material data to the surfaces in the model Surface 2002 2003 number 2002 2003 4042 Material 4042 Scatter Hit the F1 shortcut to learn more about scattering coefficients and other material specifications Notice high scattering coefficients are used on the floor and sidewalls in order to model machinery and beams Quick Estimate fast estimation of Reverberation Time
137. een 0 and 2 147 483 647 Absorption coefficients on second line must be floating point within the range O 1 the line containing 8 floating point values Descriptive text Should consist of a description of the material and a reference to the source where the absorption is documented This reference can be a link to manufactures internet page or the measurement report written as href http link When a material with an internet link is chosen the material homepage will come up by a click on the web button from within the materials List Shortcut w The absorption coefficient a for each octave band should have a value between above 0 00 and 1 00 If no data is available for upper or lower bands do not write 0 00 rather use the value of the neighbouring band e g use the 4 kHz value for the 8 kHz band 4 2 Surface List Left side of Material List window The surface list lists the material specifications assigned to the surfaces starting from the left to the right Surface number The unique number assigned to the surface in the geometry file Material number The number of the material assigned to the surface from the material library This number and material corresponds to the number listed in the material display except when e The material has been edited in the material library after the material was assigned to the surface e g its absorption coefficients have been changed e The materials were assigned on anoth
138. eep On the other hand Linear sweep May be preferable in measurements of sound transmission between rooms because partitions often provide attenuation at high frequencies Receiver model Two types of receivers microphones can be specified in the measuring system 1 1 Channel Omni 2 2 Channels Omni Figures 12 118 The omni directional receiver is sufficient in order to calculate parameters such as EDT T 30 SPL C 50 C 80 etc Notes 1 In order for parameters like LF 80 and LFc so to be calculated option 2 including the figure8 microphone must be selected and both the omni and figures microphones must be connected to the sound card If option 2 is not selected then you should uncheck the measured option for those parameters in the Define room acoustics parameters In order to obtain meaningful values for a parameter such as spi it is essential that meaningful values are entered for the Source Power Spectrum described below and that a system calibration has been performed if you do not perform any system calibration then you should uncheck the Measured option for spL and other parameters that may rely on calibration in the Define room acoustics parameters There are parameters such as Steady State Diffusivity Diffusivity ss which can be simulated in ODEON because of a large number of different types of microphone directivities are available for simulations however only the omni and figures microphones are
139. em in ODEON The chapter explains which measuring methods are used how to obtain a healthy impulse response and how to obtain room acoustic parameters as the results The chapter ends with an annex giving examples of good and bad impulse responses 1 5 END USER LICENSE AGREEMENT This legal document constitutes the complete agreement between you the end user either an individual or a single entity and Odeon A S All rights not expressly granted in this License Agreement are reserved by Odeon A S The right to use the Odeon software is sold only on the condition that the user agrees to the following License Agreement COPYRIGHT PROPRIETARY PROTECTION The Odeon software auxiliary applications and documentation are owned by Odeon A S and are protected by copyright laws and international copyright treaties as well as other intellectual property laws and treaties The SOFTWARE PRODUCT is licensed not sold You shall be held legally responsible for any copyright infringement that is caused or encouraged by your failure to abide by the terms of this Agreement OWNERSHIP OF ODEON Odeon A S retains sole title and ownership of the ODEON software regardless of the form or media in or on which the original and other copies may exist As the licensee you own the magnetic or other physical media on which the ODEON program is subsequently recorded or fixed This Agreement is not a sale of the original ODEON software or any copy thereof All rig
140. ency bands e Low frequency absorption occurs partly due to the construction itself rather than its visible surface structure Often it may not be possible to reconstruct a complete building construction in a reverberation chamber and if reconstructing only a fraction of the wall in the reverberation chamber it will have different absorption properties because it becomes more or less stiff Hard materials Hard materials such as concrete are often listed as being 1 or 2 absorbing It may sound like a difference of 0 5 or 1 is not a Significant difference However if a room is dominated by this material or if one of the dimensions of the room is a change from 1 to 2 is a relative change of 100 Materials scattering coefficients The knowledge on scattering coefficients is currently rather limited Hopefully in the future the scattering coefficients will be available for some materials Meanwhile the best that can be done is to make some good guesses on the size of the scattering coefficients and to do some estimates on the effect of uncertainty Measurements Eventually the reference data which you may compare with simulated room acoustical parameters are not perfect We must accept some tolerances on the precision of the measured parameters Receiver position s Common errors are e to base the room acoustic design on simulations in one or only few receiver positions e to place the receiver close to a surface e to use to
141. enon PG 6006 Music for Archimedes 1992 CD B amp O 101 B amp O Denmark ISO 11690 1 1996 Acoustics Recommended practice for design of low noise workplaces containing machinery Part 1 Noise control strategies ISO 14257 2001 Acoustics Measurement and modelling of spatial sound distribution curves in workrooms for evaluation of their acoustical performance ISO 9613 1 2001 Acoustics Attenuation of sound during propagation outdoors Part 1 Calculation of the absorption of sound by the atmosphere IEC 60268 16 2003 Sound system equipment Part 16 Objective rating of speech intelligibility by speech transmission index Third edition ISO 3382 2 2008 Acoustics Measurement of room acoustic parameters Part 2 Reverberation time in ordinary rooms ISO 3382 1 2009 Acoustics Measurement of room acoustic parameters Part 1 Performance spaces Affronides S 1996 Introduction to Signal Processing J Prentice Hall International Algazi R 2001 August 12 The CIPIC HRTF Database Retrieved June 16 2011 from The CIPIC Interface Laboratory Home Page http interface cipic ucdavis edu Bamford J S 1995 An Analysis of Ambisonics Sound Systems of First and Second Order MSc Thesis Waterloo Ontario Canada University of Waterloo Barron M 1993 Auditorium Acoustics and Architectural Design London E amp FN Spon Barron M amp Marshall A H 1981 Spatial Impression Due to Early Late
142. eparate values for surface hits area and the corresponding mean absorption coefficients are calculated as projections onto each of the main axis of the room The Sabine Eyring and Arau Puchades formulae require a value for the room volume which ODEON estimates from the mean free path experienced by ray tracing using the well known relation for the mean free path in a 3 dimentional room 6 72 where V is the room volume and S the total active surface area From version ODEON 6 5 the ray tracing process carried out in order to estimate the room volume assumes scattering coefficients of 1 for all surfaces rather than using the coefficients assigned to the surface in the materials list since the mean free path formula is based on diffuse field assumptions The value of S used here is the sum of the areas of non transparent surfaces taking into account whether one two or indeed none of the sides of a surface are visible inside the room Convergence criterion A certain number of particles must be sent out and followed around the room for a stable estimate to be obtained More and more particles are sent out in random directions until the value of the reverberation time has remained within 1 for at least 50 particles At the end of a run the data on how many times each surface was hit is stored Then if new materials are assigned to the surfaces the reverberation times can be recalculated instantaneously without repeating the particle tracing
143. er computer where another material library was available with different definitions of the material having this number 4 61 Note Once a surface has been assigned a material this material stays the same for that Surface even though the material has been changed in the material library the material Lis file thus calculated results stay in consistency with the materials assigned to the room even if the room is moved to another PC with a different material library To make such a new material take effect in the room please reassign the material e g using the Global Replacement option Another option is to change the absorption coefficients of a room material using the edit fields below the surface list in the left side of the materials list doing so will change the absorption of all surfaces which have been assigned that material the material will not change in the material library in the right side of the materials List Scattering coefficient some people wrongly call it diffusion coefficient A scattering coefficient is assigned to each surface This scattering coefficient accounts for the roughness of the material at the mid frequencies around 700 Hz and it is expanded during calculations in order to take into account the frequency dependent behaviour of scattering using typically frequency functions for scattering coefficients This coefficient is taken into account during the ray tracing if Room setup Calculation parameters Scattering
144. er limiting frequency fw defined by the short dimension of the panel the frequency response can be simplified to be flat i e that of an infinitely large panel below f the response will fall off with by 3 dB per octave Below the second limiting frequency f an additional 3 dB per octave is added resulting in a fall off by 6 dB per octave In the special case of a quadratic surface there will only be one limiting frequency below which the specular component will fall off by 6 dB per octave The attenuation factors K and Kw are estimates to the fraction of energy which is reflected specularily These factors takes into account the incident and reflected path lengths for ray tracing we have to assume that reflected equals incident path length angle of incidence and distance for reflection point to the closest edge on the surface all information which is not available before the calculation takes place l for f gt f l Jr f gt f Sy ee Fe fo ee ey ia I f c a F FS Sa 2Cw cos A d c LA cyt rL 2Cad where LF BA If we assume energy conservation then we must also assume that the energy which is not reflected specularily has been diffracted scattered due to diffraction This leads to the following formulae for our scattering coefficient due to diffraction s 1 K K x U s In order to compensate for the extra diffraction which occurs when a reflection appears close to an edge of a free surface the specular com
145. erated point Pt 2 1 0 1 0 1 0 Thus the following surface definition Surf 1000 Symmetric surface 1 2 2 1 will model a surface symmetric around the XZ plane Y 0 e g an end wall or a reflector If the surface is completely symmetric as above then the symmetric points can also be specified using the Mirror word which should be the last component in the corner list Surf 1000 Symmetric surface 1 2 Mirror Note You should not try to define the point 2 in the geometry file it is automatically generated 12 160 Symmetric double surface Symmetric double surfaces are pairs of surfaces symmetric around the XZ plane Y O e g a right and a left wall Surf 2 Right wall Left wall 12 22 23 13 will appear as two surfaces inside the ODEON program Thus you will have the following two Surfaces inside the ODEON program 2 Right Left wall containing the symmetric points 12 22 23 13 and the surface 2 Right Left wall containing the points 12 22 23 13 as they are defined in the geometry file Note You may not define surface 2 if you are using the symmetric double surface 2 because ODEON automatically generates surface number 2 The Box statement The Box statement defines a Box with or without top and bottom The Box statement may typically be used for Box shaped rooms and columns A special case of the Box statement is when one of the dimensions Length Width Or Height is zero in this case only one
146. eration time is much longer at low frequencies C Odeon1i2Combined Measurements IR_BetweenBuildings2 wav Raw decay curve at 4000Hz 48 M E Measured 46 eee ee p e e e e ns ce M Noise floor 444 i Onset time 424 ilf Truncation time SPL dB N O E WUE WAE a YP EE EET ee IE i 0 05 0 0 05 0 1 0 15 0 2 0 25 0 3 0 35 0 4 0 45 0 5 0 55 0 6 0 65 0 7 0 75 0 8 0 85 0 9 0 95 Odeon 1985 2013 Licensed to Odeon A S HIME SS eOngs oro ANDANON ADO I m Fig 12 11 Impulse response with prominent spikes at regular distances that indicate the presence of flutter echoes in the field between the buildings The frequency is 4000 Hz C Odeon12Combined Measurements IR_BetweenBuildings2 wav Raw decay curve at 250Hz M E Measured Noise floor Onset time Truncation time A on oinanneeeen ae H oe ie ee a ITEE E ETE EEEE ta cues Caan ec wee E E ws wu eva vce ES E E Ca WLR eae fava EEE A EEEE E SPL dB WA ne WREE g hitii 0 2 0 1 0 0 1 0 2 0 3 0 4 0 5 0 6 0 7 0 8 0 9 1 1 1 1 2 Odeon 1985 2013 Licensed to Odeon A S HIDE peponds E Weeecerrerer Perret n L i 1 7 l Fig 12 12 At 250 Hz the echoes are less distinct but the reverberation time is longer 12 126 12 127 Appendix A References ISO 8879 1986 Information processing Text and office systems Standard Generalized Markup Language SGML Anechoic Orchestral Music Recordings 1988 D
147. es The counter can be referenced within the for end loop as an ordinary constant or variable if desired so lt CountFrom gt 12 155 First value the counter takes The CountFrom value is considered an integer value If the number entered here is not an integer it will be rounded to the nearest integer value lt CountTo gt Last value the counter takes The CountTo value must be greater or equal to the CountFrom value The For statement will take CountTo CountFrom 1 loops The CountTo value is considered an integer value if the number entered here is not an integer it will be rounded to the nearest integer value The following example will produce the points 1 to 5 with the X coordinates 5 10 15 20 and 25 metres while the counter MyCounter oops through the values 1 to 5 For MyCounter 1 5 Pt MyCounter MyCounter 5 0 0 end When using For End constructs it should be remembered that point and surface number must be unique This is easily obtained by incrementing the special variable NumbOffSet appropriately in each loop An example on this kind of numbering can be found in the sample file BoxColumnRoom Par Where NumbOffSet is incremented by eight in each loop each time a new column which contains 4 surfaces and 8 points is created Sample room files ForRotunde Par BoxColumnRoom Par Unit The Unit statement is used if you wish to model in a unit different from metres The unit used in the parametric file is by default a
148. ese extreme values in selected absorption coefficients can have an extreme effect on results as well Oppenheim amp Schafer 1989 e Show reference on the web connects to internet page for selected material in material library if link is available 4 4 Opening an existing room form a version earlier than version 10 for the first time The material library has been changed radically for Version 10 The numbering of materials in the Global material library has changed and a many redundant materials have been removed Therefore some automatic update mechanism of local material library has been implemented to make the transition as smooth as possible Pre your model already had a local room library from the old version and you open it in ODEON Version 10 or later Then the Global material library will be the new ODEON library and the local room library will still be exact the same as you created in the old version If your model did not have a local material library in the old version and you open it in ODEON Version 10 Then the numbers in the local room material library will automatically change depending on 3 criteria 1 Materials from the surface list that are matching the new global material library will stay the same 2 Materials that are not in the global material library but where there is room for the original number from the surface list in the material library is added to the room material library with the same number 3 Mate
149. etric format cannot be edited in the extrusion modeller on the other hand it may be edited to any degree of freedom if needed and it is possible to make use of the benefits of the parametric format described in Appendix E E g when modelling geometric shapes such as cylinders and domes or when combining 2 extrusions in different planes or when it is appropriate to describe parts of a geometry using parameters The par file can be edited in the ODEON text editor oDEONEdit The 3Dview available in ODEON is a useful tool when investigating or modifying an already existing file load the par file into ODEON study the room in the 3DView please see the help text shortcut Fi available from within this display then make the changes in the editor which can be opened from within ODEON Using the Extrusion modeller G Odeon extrusion modeller version 3 0 C Users Claus Documents Odeon filer Rooms oes Auditorium OES File Edit Help looo i200 14 00 16 00 le o0 hooo h2 00 hoo 6 00 Modelling plane YZ Vertical cross section R 8 00 xY Horizontal 7 00 Grid and snap options i i i i i i i i i i xZ Vertical length Ortho snap Lock equal points orizontal Vertical Grid spacing 2 00 200 Metres Snap size 0 25 0 25 Metres v Snap to grid v Snap to existing coordinates V Lock H and snap Layers Use Layers Move all objects on layer ped Layer Current Name Active Col
150. f functions for coordinate manipulation and surfaces made up from coordinates is included This includes rotation around the various axes scaling and translation These functions are needed in order to insert shapes defined by the hybrid statements in the geometry with the correct position and orientation Comments and empty lines Lines containing comments and empty lines may be inserted anywhere in the file as long as they do not come between data items which should occur on one line Comment lines must begin with a colon a semicolon a slash or an asterisk The semicolon can also terminate a non comment line allowing the non comment line to be followed by a comment A series of one or more comment lines are started with a and terminated by a at any position on a line This is useful to disable a section of lines Syntax highlighting in the ODEON editor makes it easy to spot comment lines Reserved keywords predefined counters and constants The following keywords are reserved by ODEON and have a special meaning in the parametric modelling language Line folding markers BeginBlock EndBlock Constant and variable statements Const Var Point statements Pt MPt CountPt Point list statements PlistO Plist9 12 146 ResetPList0 ResetPList9 PlistaA PListB Surface statements Surf MSurf RevSurf CountSurf ElevSurf ElevSurf2 Hybrid statements Box Cylinder Cylinder2 Cone Dome
151. faces are unacceptable warped Boundary surfaces have been assigned transparency coefficients greater than zero Boundary surfaces have been assigned Material O transparent Sources are located outside the room Before investigating ray tracing you will have to e Make the boundary surfaces of the room solid by assigning materials to them For the moment it does not matter what the materials are as long as they are not transparent Material 0 Or fully absorptive Material 1 Go into the Materials Lit and assign e g 20 absorption to all surfaces use Ctrl Ins to do this in one keystroke e Place a source somewhere inside the room Sources are defined from the Source receiver List At first it may be a good idea to define a point source somewhere in the middle of the room Open a 3D Investigate Rays display and run it with e g 1000 rays with a Max reflection order Of Zero This tests whether any holes can be seen from the source position and should reveal any gross problems The tracks of lost rays will show outside the room boundaries and indicate whereabouts in the room problems occur If rays are being lost and you have an idea of which part s of the room is are leaky a number of things may be done e Reduce the value of Max accept warp IN the Room setup at the ModellAir conditions Dage Then run the 3DGeomtry Debugger Warnings will appear if surfaces have a warp or an overlap above the acceptable range This may reve
152. ffraction If this option is checked ODEON will try to calculate the sound diffracted around objects when the source is not visible from the receiver The diffraction method is the one suggested by Pierce 1974 This method includes one and two point diffraction allowing diffraction over or around single surface screens wedge shaped screen and two sided objects The Screen diffraction is only carried out for the primary source not for its image sources when it is not visible from the receiver Screen edges are detected 8 94 Figure 9 Example of a two point diffraction path displayed in Single point response 3DReflection paths as it has been detected by Odeon automatically by ODEON and the shortest path around an object is used for the calculations For more information on methods and limitations please see chapter 3 If one or more diffra ction contributions are included in a point response they can be viewed as part of the Single point response 3DReflection paths When all reflections are displayed the a shortcut Surface scattering Job calculations Global Estimate and Quick Estimate If Surface scattering iS Set to Actual all directions of late reflections are calculated using the scattering coefficients assigned to the surfaces in the Materials list Or according to the reflection based scattering method see below If the scattering coefficient is 10 the new ray direction will be calculated as 90 specular and 10 scattered
153. ffset in the wall is not sufficient to result in low frequency diffraction e Fractional Should be used for surfaces which are fractions of a bigger whole e g surfaces being part of a curved wall or a dome should not cause diffraction due to their individual area that is the individual surfaces do not provide any significant edge diffraction When setting the type to fractional the surface area used for calculating the Reflection Based Scattering Coefficient is determined from the box subscribing the room if the construction part which the fractional surface is part of is considerable Smaller that the room box the scattering might be underestimated and a higher scattering coefficient should be assigned to the surface e Transmission iS for walls which transmit sound to another room When this wall type has been selected it is possible to edit the transmission data to specify the reduction index transmission loss and to link the wall with another surface in case the wall is composed of two parallel surfaces with a distance between them and possibly with different surface materials on either side When the Transmission type is assigned to a surface 90 of the rays hitting the surface will be reflected and 10 will be transmitted the energy calculations are accomplished by multiplying each ray or particle with the appropriate frequency dependent energy parameters Transmission is covered in appendix C Surface name Lists the name given t
154. ficients in the context above are the Reflection Based Scattering coefficients if that option is activated a typical result of this algorithm is that reflections close to an edge will be handled with uniform scattering which is desirable Through empirical studies we have found that x xx 0 5 yields best results If using a value of O then all reflections are handled uniformly and if using a value of 1 then all reflections are handled using Lambert Or Lambert Oblique aS Was the case in ODEON 8 0 and earlier 8 95 8 96 9 Achieving good results The following section discusses how to obtain good results and indeed what is a good result It is not a straight answer as to how the best result is obtained merely a discussion that may provide some ideas as to what can be done in order to obtain reliable results in a program such as ODEON The desirable precision subjective limen Before discussing how to achieve good results it is a good idea to outline just what a good result is The subjective limen or just noticeable difference jnd on room acoustical parameters should give a good suggestion as to the desirable precision If the error between the real measured with some precision and the simulated room acoustical parameter is less the one subjective limen then there is no perceivable difference and the result is really as good as it can be so it would be senseless to look for more precise results In many cases it will be difficult
155. fied in the Room setup This part of the calculation only stores geometrical information and does not involve material data nor receiver position Note that this receiver independent process stores large files containing ray history These files being present after a point response calculation will speed up future calculations making use of the same sources However if these file are not erased when finishing a project you may end up with a full hard drive Either use the File Delete files Delete calculation files When all calculations in a room has been carried out or use the File Tidy directory When disk space becomes small Tidy directory Will clean a complete directory and its sub directories and delete all calculation files for all rooms A directory in this context can also be the C drive in which case it will be a lengthy process Single Point Multi Point and Grid Response the receiver dependent part Having traced rays around the room and stored the data of ray histories the next step is to place the receiver at a specific point and so to speak collect the reflections there These point response calculations are the receiver dependent part of the calculations at this point the contributions of direct and reflected sound are collected at the receiving point allowing the calculation of the results Known as Single Point Multi Point aNd Grid Response When more than one receiver is involved the receiver dependent part of the process
156. first 1 3 numbers in front of the manufacturers numbering in the material library editor The numbering of the main categories is given below e 1 99 Special materials e 100 999 Concrete e 1000 1999 Brick e 2000 2999 Ceramics e 3000 3999 Wood e 4000 4999 Gypsum e 5000 5999 Steel e 6000 6999 Vinyl Plastic Plexiglas e 7000 7999 Carpets e 8000 8999 Curtains and blinds e 9000 9999 Natural materials e g sand grass water e 10000 10999 Doors Windows furniture inventory e g organ pipes ventilation grills bookshelves e 11000 11999 Audience areas people e 12000 12999 Mineral wool e 13000 13999 Wood wool and alternative porous absorbers e 14000 14999 Slit absorbers Micro perforated absorbers miscellaneous Special Materials Material O transparent Assigning Material o to a Surface corresponds to removing the effect of the surface completely from all calculations Hence surfaces with this material assigned e Offer no hindrance to rays either in energy or direction e Are excluded from the calculated active surface area of the room and therefore do not affect the estimate of the room s volume produced by Global Estimate OF Quick Estimate Reverberation This facility can be used to temporarily remove surfaces such as doors or reflectors from the room or to define a phantom surface over which an energy map a grid is to be plotted 4 60 Material 1 totally absorbent The totally absorbent material Mate
157. first wall joins the last wall first and last point in the series of points handled to the ElevSurf must be identical in this example point 1 and point 23 are identical If an elevation surface has 22 surfaces then 23 points must be made available to the ElevSurf as in this example HHH MPt 1 23 49 62 2 02 48 22 1 1 45 3 2 68 43 85 1 45 42 40 40 98 1 45 0 34 5 2 1 30 13 2 13 000 12 152 ElevSurf 1 1 22 2 7 walls Surf 200 Floor 1 gt 22 Surf 201 Ceiling 24 gt 24 22 1 HHH Elevation surface 2 Use the ElevSurf2 statement to define a series of vertical surfaces from a series of perimeter points plus an elevation height The perimeter points are typically defined using the MPt statement The syntax of ElevSurf2 is ElevSurf2 lt FirstSurfaceNumber gt lt FirstPointNumber gt lt SectionsInElevSurf gt lt Height gt lt T B N gt lt Optional name gt The ElevSurf2 only differs from ElevSurf in that a top and bottom surface may be specified the T B N option lt FirstSurfaceNumber gt A unique number from 1 to 2 147 483647 for identification of the first surface in the ElevSurf2 Surface Using the same number but with negative sign define the surfaces and their counter parts mirrored in the XZ plane Y 0 lt FirstPointNumber gt First point number in the floor perimeter The floor points are typically MPt statement See example below lt SectionsInElevSurf gt
158. for use in other programs frequencies from lower and higher bands can be included ODEON will just ignore those bands XML extensible Markup Language has been chosen as the format for import of data for arrays loudspeakers because e It s a standard ISO 8879 1986 See also http www w3 org XML e It allows eXtending the data being exported and imported when needed by adding new attributes to nodes and by adding new nodes e Parsers for writing and reading the format are available in most or all modern programming environments e Even if a parser is not available to the persons exporting data e g Loudspeaker Manufacturer it is fairly easy to write XML formatted data the import part which is more complex is left to ODEON or similar programs The layout of the XML file To understand and learn the format the XML files installed with ODEON e g in the C ODEON10Combined ArrayXML Should be studied This document explains details of the format but most of the format is best understood from reading through the sample files The node or tree structure of XML files is complicated but best understood by studying the sample files and look in this documents when more details are needed See figure E1 and E2 to get a picture of the tree structure The following XML sample files are installed with ODEON Monopol xml Dipol xml Quadropol xml Octopol xml Dipol_Domain_Frequency xml The names of the first four files are a
159. g 3D Billard The 3pbillard display is a tool that can be used for investigating or demonstrating effects such as scattering flutter echoes or coupling effects A number of billard balls are emitted from the source and reflected by the surfaces in the room To speed up the process set the Dist per update to a higher value To visualize a flutter echo a large Number of billard balls Should be used e g 10000 balls It s easier to visualize a flutter echo if rays are only emitted in the relevant plane XZ YZ or XY If the geometry is complicated it may be hard to see the billard balls In that case toggle parts of the geometry off using the Tt shortcut Auralisation Listening to the rooms At this point you have tried calculation of room acoustical parameters operating visual display like decay curves 3D reflection paths reflectograms etc It is time to move on trying the 2 21 auralisation options in ODEON Two ways of auraliSation are available in ODEON a real time streaming convolution which produces one or two channel auralisation on the fly with some latency and off line convolution allowing mixing and auralisation with up to 300 simultaneous channels which may be assigned individual signal delay and level The result of the off line convolution is stored in files for later playback Off line Auralisation supports binaural Auralisation using headphones as well as auralisation using a loudspeaker setup Surround sound ae Rea
160. g symmetric surfaces along with modelling entities such as countSurf Box Cylinder etc and in particular to make the automatic surface numbering work without any problems when the numboffset is set tO Auto If having problems loading a room due to the reasons just mentioned ODEON will either give an error message that surfaces are repeated in the geometry file or that materials are not applied to all surfaces In these cases you may wish that ODEON use the old numbering mechanism this can be done using the version4 flag in the par file As the first line in the geometry file just after the sign type Version4 TRUE 1 14 Once the old incompatible code ends Versiona may be set to FALSE again 1 3 How to upgrade or update your current license For ODEON 9 1 and later versions your ODEON software license is stored in a Smart Card based hardware key the Rockey 6 Smart dongle As an ODEON user you can have 4 ways of updating or upgrading the program after the installation of ODEON 9 1 e Version number can be updated free of charge in between the full versions at www odeon dk E g from version 9 1 to version 9 2 e Your version can be updated to a full version number E g version 10 by requesting a remote licence update e For time limited licenses time limitations can be removed or the Run time hours available can be updated by requesting a remote licence update e The Edition can be upgraded to combined if the curre
161. g binary distribution files can be found at the download page at www clifgroup org If apparently the data of interest is not available from the manufacturer of interest then assist the Clf group by encouraging the manufacturer to make such data available free tools for this purpose can also be obtained at the CLF group s homepage File location for directivity files No matter if files are in the CF1 CF2 or in ODEON s native So8 format the files should be stored in ODEON directivity directory which is specified inside ODEON at oOptions Program setup Directivity files location The files may be stored in subdirectories to this directory allowing loudspeaker directivities of different brands to be located in separate directories e g C ODEON DirFile ManufacturerA OF C ODEON DirFile ManufacturerB We have taken the opportunity to create a number of folders for manufactures which do supply loudspeaker directivity files in the CLF format Using these predefined directories it is easier to move a room from one PC to another without breaking file linkage 10 4 Creating new directivity patterns in the ODEON So8 format Tools for creating directivity patterns in the ODEON So8 format can be found at the ToolsiCreating directivity patterns Menu entry inside the ODEON program The tools allow you to expand the set of source directivity pattern files available for point sources in ODEON The ODEON directivity pattern file Version 3 or later contains
162. ge diffraction with surface scattering Each of the two scattering effects is modelled as frequency dependent functions The benefits are two fold e Separating the user specified surface scattering coefficient from the room geometry makes it easier for the user to make good estimates of the coefficients that will be in better agreement with the ones that can be measured In many cases a scattering coefficient of say 5 for all smooth Surfaces may be sufficient e Scattering due to diffraction is distance and angle dependent and as such it is not known before the source and receiver are defined and the actual ray tracing or image source detection takes place An example on this is that a desktop may provide a strong specular component to its user whereas it will provide scattered sound at remote distances The method has several advantages not only does it make life easier because the same scattering coefficient can be used for different surfaces no matter their size it also allow better estimate of the actual scattering occurring at a reflection point because scattering caused by diffraction is not fully known before the actual reflections are calculated thus angles of incidence path lengths etc are known In order to allow these features to be included in predictions the reflection based scattering coefficient s combining the surface roughness scattering coefficient s with the scattering coefficient due to diffraction sg is calcula
163. ge material library and material liSt cece eeeeeeeeeee eee eeeeeeeenenas 4 63 Material TOOIDAF siicsiccntesninntiessannvnessnetenesviduseuseid A EEA E 4 63 4 4 Opening an existing room form a version earlier than version 10 for the first time 4 64 5 PUAN AOTT eona a E I E TERI 5 66 6 Calculation PrincipleS sssssssssssssssnsssssssssnssnssrsnsssnnsnsenssnnnssnsnennsnesnsnsenensnnesnnnne 6 72 kr Global doc Tn OS sie N E E E 6 72 6 2 EA UCK ESAO aeae E E E E E EEE 6 72 L Global Estimate cccceccecceccecceeceeceeceeceeceeceeeeeeeeeeeeeeeeeeeeeeeeeeseeeeeneeseeneeneeneeness 6 73 6 3 Calculation of Response from Sources tO RECEIVESS cccecceeeeeeeeeeeeeeeeesseeeeetteeaes 6 73 Receiver independent ray tracing cccccccceeeeeccsceeeeenenennnneeeeeeeeseeeeeanennaaaneeeseeenegs 6 74 Single Point Multi Point and Grid Response the receiver dependent part 05 6 74 Summarizing the calculation method used for point response calculations in ODEON 6 76 Vector Based Scattering reflecting a Late FAY ccccccccee cece eee e teen eee eeeeeeeeeeeeeeenenees 6 76 6 4 The Reflection Based Scattering coeffiCient cccceeee cece cece cece essen eeeeeeeeeeeeeeees 6 77 5 5 ObpIGUE LaMDGCIT s ccccecccssacasantsnsnsanaeetesersidntasdantsiaatenseteaeiaistereaarneneesecnsandiaritess 6 81 6 6 Diffraction over screens and round objects Screen diffraction ccceeee ee eees 6 83 6 7 Radiated ray
164. ging Rel standing Of Absolute Most programs will probably export as Absolute ODEON has the two other options in order to allow automatic aligning and sort of transducers relative to the upper rel hanging or lower rel standing transducer The origo of the transducers can be offset using the node coordSysoffset node FarFieldDistance 1 IN metres 1 indicates that ODEON should make its own estimate of the far field distance For distances greater than FarFieldDistance ODEON will use a pre calculated balloon calculated for that distance This far field balloon is calculated and handled entirely by ODEON FarFieldResolution 2 Far field balloon resolution in degrees 1 2 3 5 and 10 degrees allowed NumberOfSubBands 6 Frequency resolution per octave band applied for phase summation in the calculations Can be 3 6 9 A resolution of 6 is suggested as a good compromise between calculation time and quality of results Nodes to ArraySource Position Orientation CoordSysOffset EQ 12 139 Transducer there can be multiple Position Node Attributes to Position x 1 ee Z Uses the same coordinate system as in ODEON and as in the room to be imported into Defaults to 1 1 1 and can easily be changed from within ODEON Orientation node Attributes to Orientation Azimuth 180 around vertical axis counter clockwise is positive Elevation 90 up is positive and down is negative Ro
165. gram and extend or correct it using tools which come with ODEON Appendix G gives an overview of which file formats can be used with ODEON No matter which approach you choose for modelling always check the validity of the models The room model must form a almost closed enclosure It should also be almost free from warped twisted duplicate or overlapping surfaces ODEON has several tools for checking models for such problems The tools are presented in section 3 4 It is suggested that you always use these tools when working on models of some complexity 3 1 Guidelines on room modelling Whether you choose to model your rooms by typing your rooms directly into a text file by using the ODEON Extrusion Modeller or by using a CAD program there are considerations that are common to either case Some guidelines of general nature are given below Default coordinate system To make it as easy as possible to operate ODEON the following orientation of room geometries Should be applied using a concert hall as the example e X axis pointing towards the audience e Y axis pointing to the right as seen from the audience e Z axis pointing upwards Recommended size of a surface An important theoretical consideration concerns the size of surfaces in a room model The classical laws of geometrical acoustics are such that for the purpose of calculating how much energy is reflected all surfaces are considered to be infinitely large in co
166. h few surfaces this is easily accomplished however for rooms with thousands of surfaces this can lead to huge number of images sources which for geometrical reasons are not valid anyway Instead another approach is used in ODEON early rays up to the transition order Specified in the room setup are used in order to detect possible image sources A number of early rays are generated ODEON suggest a number based on room dimensions transition order and surface sizes The rays are reflected specularily and each time a new combination of reflecting walls are found a new image source is added to an image source tree The number of images stored in the image source tree after this process is usually much lower than all combinations of reflecting walls but the images are all valid in the sense that each of them can be seen at least from some receiver position in the room Late part finding the secondary sources The late ray tracing is different A number of Late Rays specified in the Room setup are emitted from the source and reflected according to the vector based scattering method described later taking into account scattering due to surface size and surface roughness At each reflection point of a ray a secondary source is generated if the reflection order is above the Transition order The early and late processes described use ray tracing which is carried out taking into account the Impulse response length and the Max Reflection order aS Speci
167. h a single plane at 45 which might then act like a reflector Concave curves naturally focus sound energy and since focussing is a fault we wish to model we must try to arrange that it be preserved However this does not mean that a large number of subdivisions are the solution Using many surfaces in the model will e Make the model visually complex and increase the probability of errors in the model typically small leaks may become a problem e Not combine with the image source theory used for the early reflections point sources e Increase the calculation time In order to calculate focusing from concave surfaces the wall type of surfaces forming a concave shape should be set to fractional in the Materials List Otherwise the concave surface will scatter sound too much taking into account the small areas of the individual surfaces forming the concave shape rather than the total area of the concave shape The Reflection based scattering method would produce too much scattering in this case Subdivisions about every 10 to 30 will probably be adequate to reproduce focussing trends of concave surfaces without excessive number of surfaces thus walls in a cylindrical room may be modelled from 12 to 36 surfaces A cylindrical column which disperses energy may probably be modelled from say 6 to 8 surfaces What to model How to model an audience area Modelling each step between the rows in an audience area is not recommended
168. h the 2 impulse response If the user wishes to process another impulse response he should crop the desired part of the recording and save it as a new file zoom the relevant part then save it using the c shortcut Once the file has been saved it is automatically opened in the Measured Response Window 12 121 C Odeon12Combined Measurements Clapping wav Raw decay curve broad band Jv E Measured M Noise floor Onset time Truncation time 10 alts 20 225 30 SPL dB ii I I Lal 35 he stall ee 4 sarah ooh 0 8 0 6 0 4 0 2 0 2 0 4 0 6 0 8 1 1 2 1 4 1 6 1 8 2 2 2 2 4 2 6 Odeon 1985 2011 Licensed to Odeon A S ume Geconds 40 45 50 z595 60 Fig 12 5 An example of recording that contains four impulse responses in a row Hand claps have been used for excitation ODEON detects the second impulse response as being the strongest one and sets an onset and a truncation time for it Calculation of the onset time is performed on the broadband signal as suggested in ISO 3382 1 A 3 4 and not for each Octave band separately An interesting case for the same impulse response is illustrated in Fig 12 6 At 125 Hz the signal to noise ratio is very poor for the selected impulse response and its length is too short so that a stable noise floor cannot be derived Instead of a truncation time ODEON displays an estimated end of the response No acoustic parameters can be calculate
169. he addition of energy contributions from different reflections in a response is valid This manual will not cover the use of the individual parameters in depth and suggestions on ideal parameters choice should only be sought of as a first suggestion instead refer to relevant literature e g some of the following references for a further discussion on parameters and design criterions Auditorium acoustics as Concert Halls Opera Halls Multipurpose halls etc are dealt with in Beranek 1996 and Barron 1993 where different halls around the world are presented along with judgement of their acoustics and guidelines for design Short guidelines on which values to expect for Clarity and G in concert halls based on some simple design parameters as width height floor slope etc are given in Gade 1997 Some recommended values for room acoustical parameters are given in the following table symphonic music Lome 5 1 eee eee field Fraction Early Support gt 13 dB es Total Support gt 12 dB Se Recommended values for objective room acoustical parameters ISO 3382 1 2009 in large music rooms with audience according to Gade Gade 2003 Subjective limen as given by Bork Bork 2000 and Bradley Bradley 1986 dB Early Decay Time and Reverberation time The energies of all the reflections received at the receiver point are collected in histograms with class interval specified in the Room setup Impulse response res
170. he full case there are 36 lines of data for each frequency The first 36 lines are for 63 Hz the next 36 lines for 125 Hz and so on As a minimum there must be 1 36 8 lines in a full input file e 1 line is vertical upper plot 0 12 o clock plot when looking from the front of the source towards it e g at a loudspeaker membrane e 10 line is horizontal left plot 90 9 o clock plot e 19 line is lower vertical plot 180 6 o clock plot e 28 line is right horizontal plot 270 3 o clock plot 10 104 An example Full_Omni dat on the full input format can be found in the DirFiles So8_ASCII_input_file_samples directory created at the installation of ODEON When the directivity pattern is rotationally symmetric SYMMETRIC The first non comment line of the file should start with the word SYMMETRIC In the symmetric case there is one line of data for each frequency As a minimum there must be 1 8 lines in a symmetric input file The symmetric sources could be a Trumpet Or the Omni directional source An example Symmetric_Omnidat on the symmetric input format can be found in the _ DirFiles So8_ASCIL_input_file_samples directory created at the installation of ODEON Creating a new directivity pattern using a text file as input Once the text input file has been created in one of the formats specified above e g in the ODEON editor ODEONEdit it can be translated into an ODEON Directivity file which can be applied to
171. he snap is 0 25 and X of the clicked position was 0 15 then the X coordinate of the point will be 0 25 if the Snap to grid option is enabled It is possible to fine adjust the coordinates in the Point editor lower right corner of the Extrusion modeller If Snap to existing points is enabled the X Y or Z coordinates of already defined points are also Snap able Ortho snap Enable Ortho snap if the surface to be drawn have many edge angles of 90 or 270 degrees The option can be turned on and off while drawing a surface Lock equal points When this option is enabled it becomes possible to move points in multiple surfaces if their X Y or Y Z or X Z coordinates are equal This is useful for multi level rooms Snap to existing coordinates Makes it easy to draw new point making use of horizontal or vertical coordinates in existing points even when the do not match current snap size Lock H and V snap If this option is checked then Horizontal snap size will automatically be updated when the vertical snap size is changed and vice versa Relative or absolute extrusions Use the ctritH shortcut to toggle between relative or absolute extrusions in the Surface editor table When extrusions are displayed in relative measures an extrusion may be defined as z 10 and dz 5 telling that the extrusion starts at a height of 10 and has an extrusion height of 5 If toggling to absolute extrusion then the same extrusion is displayed as zi 1io and z2 15 tel
172. his parameter is suggested in Bradley amp Soulodre 1995 and has a very high correlation with the subjective parameter Listener envelopment LEV Stage Parameters Stage parameters are calculated as a part of the Single Point response Auditorium and Combined versions only if the job only contains one active source the active source is a point source and the distance between receiver and source is approximately 1 metre 0 9 to 1 1 metre The parameters are called Support for early late and total energy and are described in more detail in Gade 2003 Early Support or ST1 E ST 20 100 dB early E 0 10 Late Support ST E 00 1000 dB late Ei 0 Total Support E ST ota r oa dB 0 10 STeary Or ST is used as a descriptor of ensemble conditions i e the ease of hearing other members in an orchestra STjae describes the impression of reverberance and STiotai describes the support from the room to the musicians own instrument If the early late averaging is turned ON averaging in time is performed as for the other parameters In case of the stage parameters the following limits of time intervals are used 9 ms 10 ms 11 ms 18 ms 20 ms 22 ms 900 ms 1000 ms and 1100 ms IACC Inter Aural Cross Correlation Since the hearing process is binaural the spatial impression in a concert hall can be quantified by measuring the inter aural cross correlation between the left and right ear canal ISO 3382
173. hough To allow reading the XML document by eye consider to set the xmLDocument Options doNodeAutoIndent if that option is available in your programming environment XML document content Many of the data given in the XML file is optional if not given in the XML file ODEON will set a default value The nodes and Attributes of the tree structure is described below and should be compared with the XML file to keep on track See also figure E1 and E2 Main node all nodes below included ArraySource Main node in the XML file which holds the entire array Attributes to ArraySource ODEONArrayVersion 10 0 If this number is higher than the version number known by the READER then the reader should not accept to read on This version number is the version number of ODEON when the format was last revised That is to say if the READER is ODEON 10 0 or another program aware of ODEONArrayVersion 10 0 then it should not accept data written in ODEONArrayVersion 10 2 This on the other hand implies that if your WRITER does not use any specifications added in a later ODEONArrayVersion then you might consider using the lowest version number possible to make it compatible with READERS not knowing of the higher version READER should assume no more than 4 decimals in the version number Gain 8 Overall in dB per octave band defaults to 0 Delay 0 007 Delay in seconds of the entire array ArrayCoordSys Absolute Can be Rel han
174. hould furniture such as tables chairs and shelves be included in a model of an office If a table plate is close to a source or receiver point then it is likely to produce a strong specular reflection at the receiver so if this is the case then it should be included Furniture such as shelves and screens in large office environments which subdivides the room breaking up long reflection paths and introducing extra absorption and scattering should neither be omitted Furniture at more distant locations in the room which does not produce any strong early reflections to the receiver can be greatly simplified or even omitted from the model as long as the extra absorption and scattering produced by that furniture is somehow included on other surfaces in the same regions of the room Orientation of surfaces does tilt of a surface have any significance on room acoustics Small changes to the orientation of surfaces can indeed cause dramatic changes Making dominant surfaces slightly off angle can cause extra scattering in the room almost as if extra scattering had been assigned to the surfaces in the room A classical example on this is the box shaped room where a flutter echo can be removed changing the angle of a surface by a degree or two 3 2 Modelling tools There are a number of choices available for modelling rooms for use with ODEON No matter the choice of modelling the room used for calculation with ODEON is stored in a file with th
175. how Gria button Note If the Define Grid button is disabled this is because some process is open which requires data to be saved In this case it is probably the Estimate Reverberation display that needs to be closed To find this open window use the windows menu item on the menu bar Other displays containing calculation processes may cause the same kind of disabling of miscellaneous options Close the Define Grid dialog to save the grid definition Calculate grids Click the job list button again Activate Grid option from the Job List check the Gria option for job 1 4 and click the run al button ODEON will now start calculating the grid response for the four jobs this may take a while When the calculations have finished select job number 1 in the Job List and click the view Grid Response Dutton to view the grid results To learn more about the results and options available from this display use the Fi shortcut El 3D Investigate Rays 3D Investigate Rays Visualises the ray tracing as it is carried out during any point response calculation By default its calculation parameters are also set up as the parameters used for the point response calculations multi and Gria This display is a very valuable tool for debugging of new models e g to detect missing or misplaced surfaces It may also give an impression of what is happening in the calculations e g the effect of the scattering assigned to the surfaces Click the ok button then click
176. hted speech at 4 meters Nominal A weighted sound pressure level of normal speech at a distance of 4 m from the sound source The levels are summed up over the octave bands from 125 to 8000 Hz A weighted background noise The quantity shows the level of background noise summed up over the octave bands from 125 to 8000 Hz Ey Edit Room Acoustic Parameters in ODEON In the latest ODEON version the user is able to edit the room acoustic parameters calculated in the point response or to define his own ones The Room acoustic parameter list WINdOW allows several manipulations such as change of the limits for the reverberation time or editing the formula corresponding to each room acoustic parameter An additional feature is the manual definition of the grid range The user can define the type of a parameter Reverberation T30 SPL Centre Time Formula Dietsch The values of the energy intervals on the left of the window can be used as variables in a parameter expression When someone wants to use an energy interval from a specific time point t to the end of the response he has to make use of the predefined whole response length and subtract the interval from t 0 sec to t e g E_Omni50ms_Total E_Omni_Total E_Omni50ms For a formula type the equation can be written explicitly in the white box A list of all mathematical expressions available in the edit formula mode is given in Appendix F 7 91 7 92 8 Calculation Parameters Room Setup and Def
177. hts are reserved by Odeon A S GRANT OF LICENSE In consideration of payment of the License fee Odeon A S grants each customer a private person or a company registered in a country a non exclusive right to use the ODEON software This Agreement grants you the right to make copies of the software for archival purposes and to copy the software on the hard disk of your computer The software may be loaded onto multiple computers but can only be fully operational on a single computer at any given time The computer operating the ODOEN software needs to have the hardware key delivered with the software attached to the USB port HARDWARE KEY Granting of a license is bound to ODEON software use with a hardware key The hardware key holds the license information and determines the version and edition of the Odeon software that can run when the hardware key is attached to the computer If a hardware key is defective during the warranty period first licensed year Odeon A S will replace the hardware key The customer will pay the hardware key fee for replacing the hardware key should it become defective after the warranty period The hardware key contains the name and country of the licensee which are displayed in the software on print outs from the software and on graphics exchanged from the software LICENSE RESTRICTIONS The modification adaptation translation reverse engineering de compiling disassembling attempt to discover the source co
178. ians Inverse Tangent in radians Inverse Tangent II in radians Inverse Sine in degrees Inverse Cosine in degrees ArcCosD X Inverse Tangent in degrees ArcTanD Y Inverse Tangent II in degrees ArcTan2D X Y Exponential Exp Natural Logarithm m Logarithm base 10 Losi 000 Logarithm base 2 0520 Square Su Square rooi Syn Sand 1 Sian O 0 Sian 1 Mind TABE MaX Ma2 2 12 173 12 174 Appendix G Importing geometries compatibility ue MicroStation peo ArchiCAD IntelliCAD 7 AutoCAD en wha nd f 3dstudioMAX ED aas SONarchitect IFC2SKP Odeon Google SU2Odeon 3 Editor 3 SketchUp i Odeon Import Odeon Extrusion Odeon Export ees gt Optional T N 7 gt Recommended 3D modelling program Converter Cant cad geo 12 175
179. ifferent materials It is possible to select among the defined sources However the source position will only have minimal effect on the global estimated reverberation time unless strong coupling effects are present in the room ET Room setup calculation parameters At this point you should have an idea of the order of size of the reverberation time To continue the series of calculations you should enter the Room setup and specify the impulse response length The Impulse response length Should cover at least 2 3 of the decay curve in this case 2000 ms Should be sufficient To learn more about the other parameters available from this page use the Fi shortcut L amp lGlobal Estimate reliable method for estimation of reverberation time RUN Global Estimate and let it run until you are satisfied that the decay curve has become stable then press the Derive results button Note the longest reverberation time The reverberation time differs from the values calculated by Quick Estimate because the room shape and the position of absorbing material are taken into account It is important that the Impulse response length in the Room Setup iS at lease 2 3 of the reverberation time 2 31 calculating point responses At this point we are ready to calculate point responses Two different point response calculations are available in the industrial edition e Multi Point Offering room acoustical parameters for all the receivers defined in the Receiver
180. ified by the width and height Dome2 may typically be used for modelling dome shaped ceilings The syntax for Dome is Dome2 lt Number gt lt NumberOfSurfaces gt lt Width gt lt Height gt lt RevAngle gt lt optional name gt lt Number gt A unique number from 1 to 2 147 483647 for identification of the first point and surface in the Cone Using the same number but with negative sign defines the surface and its mirrored counterpart in the XZ pane Y 0 A Cone will take up several point and surface numbers which must all be unique lt NumberOfSurface gt Specifies the number of surfaces in one horizontal ring of the dome around 16 to 24 surfaces per ring is suggested ODEON will automatically calculate the number of subdivisions in the vertical level If the revolution angle is 180 the number is stored in the ONVert variable would have been 9 in the example above The ONVert variable may help when connecting a Dome2 to a Cylinder2 in order to specify the correct number of surfaces in the cylinder lt Width gt Width at the beginning of the dome The width must always be greater than zero lt Height gt The Height must be different from zero If the height is less than zero the orientation of the dome is inverted Height must be different from zero and less or equal to 2 Width lt Revangle gt Revangle must be within the range 360 and different from zero If RevAngle is 180 a half cone is generated if its 360
181. in detection algorithm In order to limit the complexity and time consumption of the detection there are some limitations to the type diffraction paths ODEON can detect In order to understand the limits here is a short and slightly incomplete description When a source is not visible from the receiver ODEON will try to detect the shortest diffraction path from source to receiver in the following way 1 A ray is sent from source towards the receiver and the first surface hit is registered A 2 Aray is sent from receiver towards the source and the first surface hit is registered B A diffraction path should follow the path Source A B Receiver where A and Bn are the nt and m point on an edge of each of the surfaces The shortest path with full visibility between the three sub paths Source A An Bm and B Receiver is used for the further calculations In cases where there is another surface which blocks the paths between one of the sub paths ODEON will right or wrongly not detect a diffraction path An Bm An An Bm An Bm R N N AN i S S S I a b C d Figure 6 8 Diffraction paths and their detection a Odeon detects a 1 point diffraction path over a thin screen b Odeon detects a 2 point diffraction path over a wide barrier C Odeon fails to detect a diffraction path because the path from A B is obscured by a third surface in fact it s a 3 point diffraction path d Odeon detects a diffraction path over two
182. include a sub directory name it probably should e g Balloon LspManufacturerName SpeakerModel23 CF2 Balloons can be in CEL y GF2 and sos formats Delay 0 012 Delay of that transducer in seconds 12 140 InvertPhase false If phase is inverted 180 defaults to FALSE SampleRate 9 44100 Hz OF 48000 Hz Not in use yet Specifies the sample rate if the filter for a transducer is a FIR filter PhaseCF2 false True if directivity balloon containing phase angles should be used for the transducer See section on phase balloons at the end of this appendix For transducers which have been assigned a directivity pattern in the Common Loudspeaker Format CF2 version 2 the transducer may belong to multi part speaker e g having separate balloons for the low frequency unit and the high frequency unit in a loud speaker I that case there may also be assigned a filter e g low pass and high pass to each transducer This is what CLFPartNo CLFPartMax and CLeFilter iS for CLFPartMax 2 How many transducers with CLF2v2 balloons belongs to this speaker array CLFPartNo 1 Which part of a multi part CLF is this transducer e g part 1 or two of a two way speaker CLFFilter true Is a filter assigned to the transducer in the CLF2v2 file e g a low pass or a high pass filter Domain Frequency So far options are Frequency for beem steered otherwise octave future should include Time in which case an a
183. inds of point response calculations the single Point Response the Multi Point Response and the Grid Response e Single Point Response The Single Point Response iS Calculated for a selected receiver position which must be defined in the Source Receiver list The Single Point Response iS the most detailed calculation method allowing e Prediction of room acoustical parameters including stage parameters e Display of predicted Decay curves e Tracking of individual reflections in a reflectogram and display and tracing the reflection s in 3D displays of the room e g for tracking down echo problems e Auralisation see chapter 5 Multi Point Response Multi point response Calculates room acoustical parameters for all the discrete receiver positions defined in the source receiver list fed Grid Response Grid Response Calculates room acoustical parameters for a mapped receiver area The surfaces over which grids should be calculated are selected in the Define Grid display Auralisation The Auralisation features are available from within the job list Auralisation is based on impulse responses BRIR s and Surround Impulse responses which may be calculated as a part of the Single Point Response Fast and easy to use binaural auralisation is provided by the streaming convolution facility to learn more about this facility use the online help from within the JobList If greater flexibility is needed a separate auralisation display a
184. ine Grid The Calculation parameters specify how calculations are carried out in ODEON and as a starting point ODEON suggests values that can be considered suitable for most calculation parameters Select one of the presets Survey Engineering OF Precision representing the quality of results desired ODEON will adjust the calculation parameters accordingly There are a few additional parameters in the General settings that may also need attention the Impulse response length and Number of late rays The Specialist settings need normally not be adjusted Impulse response length Job calculations and Global Estimate Always specify the Impulse response length It Should be at least 2 3 of the reverberation time the longest reverberation time over all 1 1 octaves It determines how many milliseconds of decay curve are to be calculated It is a key parameter if it is shorter than app 2 3 of the reverberation time in the room then T3 cannot be calculated because the dynamic range of the decay curve is less than 35 dB then it will be displayed as in result displays For reliable result it is recommended to use an Impulse response length Which is comparable to the estimated reverberation time To get an estimate of the reverberation time in a room use the Quick Estimate available in the materials list The maximum allowed Impulse response length IS 32000 ms Number of late rays Job calculations The number of Late rays determines density
185. information on the sound levels for the eight frequency bands 63 Hz to 8 kHz in dB for each 10 azimuth and 10 elevation These files are 10 102 binary and have the extension sos An example on a directivity pattern is the pattern stored in OMNLSO8 Entering a directivity plot using the Directivity polar plot editor i A aE a AE T ati The easiest way to enter a s s o os SENG F AM FE ESE new directivity plot is to use _ Te the built in polar plot editor which allows building a directivity plot from a vertical and a horizontal polar plot Enter the dB values sound pressure level for the horizontal and vertical plots at the selected frequency band in the corresponding tables The angular resolution is 10 degrees If data are not entered for all angles e g if the data are Se not available ODEON will tuS aa UU L am mimos do interpolation between the angles entered For angles between the polar plots ODEON will perform elliptical interpolation wh j x se gt E ARTE ot are ik ve ie e rw Abd s e D a tama tee ade Ka ano m Ita seamen mi me smen e Equalization If the source to be used in ODEON has a fixed frequency dependent sound power level the equalization option in the Polar plot editor is used for entering the dB values Calibration Three different options are available in the Polar plot editor e If No calibration S selected ODEON will use the
186. ing plane then a chair may in effect be considered an extrusion which excludes the top and three of its sides In this example we will create a chair with the seat dimensions 0 4 x 0 4 and a back rest with the height of 0 4 Legs and other small details should be omitted To make things easier do the modelling around origo then move the chair to its final location when finished When modelling around the origo it becomes easier to read the dimensions of the seat of the chair and to use grid and snaps without the need to calculate dimensions of the seat e Set the snap size s to 0 4 metres e Click the 4 points in the seat of the chair Insert Or Esc toggles point input on off e Change the z coordinate in the chair to 0 4 metres in the Surface editor to define seat height e Change az to 0 4 metres in the in the Surface editor in order to define the height of the back of the chair Uncheck Top in the surface editor Uncheck the 3 sides which are not the back of the chair in the Point editor Finish the surface by pressing the Insert Or Esc key Finally move the chair to the desired location using the left mouse button Using the circle tool and the mirror Loo looo hoo Loo lo o0 hoo l 1 00 hoo 0 00 O00 god 0 00 1 00 100 1 00 1 00 T T O n T 2 00 200 2 00 2 00 1 00 j1 00 j1 00 ji 00 In this example a table plate with circular ends is modelled a First a circle is created b Then half of the circle
187. ing back wall using the ceiling cylinder points which is still stored in PListB 12 170 Dome2 and cylingder2 x 2 room par HHH Se const H 5 Const L 10 Const W 15 Const N 12 Const HCurve 4 NAMWARWNE MRotateZ 90 Cylinder 1000 N W 2 180 H N 10 Storres PListA for later use with floor 11 PList0O PListaA 90 12 MTranslate 00 H 13 Dome2 2000 N W HCurve 180 Halfdome 14 MReset 15 MRotateZ 90 16 MRotateY 90 17 MTranslate 00 H 18 Cylinder2 3000 ONVert W HCurve L n Cylindric ceiling 19 MReset 20 Ptl 0W 20 21 Pt2 LW 20 22 Pt30W 2H 23 Pt4 LW 2 H 24 Surf 1 Floor 25 2 PList0 2 26 done with PList0 its a good habit to Reset it 27 ResetPList0 28 Surf 2 Side Walls 29 1243 30 Surf 3 Back Wall 2 PListB 2 31 F Defining surfaces with concave edges Most surfaces in the geometries used with ODEON will probably have convex edges rectangles cylindrical surfaces etc however in ODEON it is possible to define surfaces with cavities even surfaces with holes Such surfaces are defined just like any other surface by creating a list of corners where the listing is obtained by travelling around the surface s edge in either direction Below are two examples one with a donut shaped balcony floor and another with a cylindrical window opening in a ceiling In the donut example two rings of corners are created using the CountPt statement notice that the point 100 is equal
188. ion may lead to an excessive number of surfaces and may not work with poly faces Max point margin If points in the pxr file are within this margin the points will be considered equal Allowing a certain amount of point margin will allow the Glue function to perform better if the coordinates in the model are not exact However if you have modelled both sides of a surface e g outside and inside surface of a balcony front edge the Max point margin Should be smaller than the distance between these surfaces otherwise the points on either side of the surface will be considered the same with disastrous results Max warp ODEON will split four point surfaces into 2 three point surfaces if the surface s warp exceeds this value The glue option on the other hand will try to glue surfaces as long as this does not lead to a surface exceeding the max warp Editing the imported geometry It may be necessary or at least desirable to make changes to geometry after it has been imported The 3DView display which displays the geometry once it has been imported is a useful tool for this purpose please see the context sensitive help available in this display from within ODEON for further details shortcut F1 Example Importing the supplied ElmiaDXFSample dxf and changing its Origo Try importing this axf file which is located in the room directory To make the operation of ODEON as smooth as possible it is desirable to move the Origo of this ge
189. ious comment fields in ODEON the material library is not fully Unicode enabled yet In particular Unicode allows text in Asian character sets Japanese Chinese and Korean to be saved from within the ODEON application It is also possible to save text which is a mix of texts in different character sets When upgrading to version 10 or later the order of materials in the Material list has been revised please see Chapter 4 Features introduced with version 9 1 With ODEON 9 1 is delivered a new type of Dongle which makes it easier for the user to install new upgrades This is more thoroughly described below in chapter 1 4 and at www odeon dk dongle update Version 9 1 has a far better auralisation option than previous versions for presentation through 2 loudspeakers called Super stereo With Super stereo you can make 2 loudspeakers have a much more spacious sound with the right frequency response for this type of auralisation In Chapter 2 an intro on how to do this can be found As an example of use if you are both musician and acoustician you can make an auralisation of a recording of your own music played in a room you have modelled in ODEON so it sounds right on your own loudspeakers 1 13 Some outdated directivity files such aS TikNorm sos have been replaced by TikNorm_Natural sos which is smarter for auralisation use where there might be a risk of adding the overall frequency response twice to auralisation output once from the di
190. irect indirect consequential or incidental damages resulting from any defect in the software update version or its documentation or arising out of the use the results of use or inability to use the product even if ODEON has been advised of the possibility of such damage or claim LIMITED WARRANTY ODEON A S make no warranty or representation either expressed or implied including but not limited to implied warranties or merchantability and fitness for a particular purpose with respect to this product As a result this software is sold as is and you the licensee are assuming the entire risk as to its quality and performance No ODEON A S Distributor agent or employee is authorized to make any modification extension or addition that will increase the scope of this warranty UPDATE POLICY ODEON A S may create from time to time update versions of the ODEON software Odeon A S reserves the right to make changes to the software or its documentation without notice Major updates e g from Odeon 11 to Odeon 12 will be made available to registered users who have a valid Maintenance and Support Agreement or who purchase an upgrade Minor service updates e g from v 12 0 to 12 01 or 12 1 may be made available for download and may also be used by the licensee without a valid Maintenance and Support Agreement if the hardware key permits running the update USE OF ANECHOIC ORCHESTRA RECORDINGS DELIVERED WITH THE SOFTWARE The Odeon Auditor
191. is deleted c Finally the surfaces is mirrored in a horizontal mirror at y 1 3 48 creating a circular surface To create a circular surface first draw a line a surface with two points in order to specify centre and radius of the circle then use the ctrit o shortcut to activate the circle tool and accept to create a circle from 12 points If the circle tool is clicked when the selected surface contains less than two or more than three points then a help text is displayed this text will also explain about ellipses Make a circle half a circle Delete the 5 upper points in the circle in order to reduce the circle to half a circle At this point you should have created the half circle in middle of Figure above Mirroring the surface In order to create the complete table the mirror functionality can be used select the horizontal mirror and specify the coordinate of the mirror line in the Figures the coordinate was 1 00 Select the first of the two points to be connected across the mirror line and finally use the Mirror shortcut ctrit m to create the full table The position of the mirror is easily changed if holding down the snit key while pressing Right mouse and moving it if performing a very significant move in the horizontal or vertical direction this will toggle between a horizontal and a vertical mirror line blue dashed line Mirror manipulation Mouse operation Move mirror line toggle between vertical and horizontal mir
192. itle bar of the 3pview will be blue or some other colour indicating that this is the active window Being the active window the 3pview menu item is added to the menu bar next to the Toolbar dropdown menu You can operate the functions of the window using this menu or the shortcut keys displayed in the menu z 4 Define sources and receivers Before any calculation can be carried out in ODEON one or more sources will have to be defined Of course a receiver will also have to be defined in order to calculate a point response In this guided tour we shall define a point a line and a surface source Finally we define a receiver Click the Source receiver list button at the toolbar to open the Source receiver list from which sources and discrete receivers are defined If the Source receiver list is already open but hidden behind other windows etc clicking this button will rearrange the windows as needed Obetine a point source Click the New point source Dutton in the local toolbar at the right side to open the Point source editor Enter the values x 3 metres y 2 metres and z 1 2 metres If you are not sure of the position of the source you can select the 3D Edit source display If you do so you should notice how the menu item 3D Edit Source appears on the dropdown menu when this window becomes active The 3D Edit Source Receiver Menu will allow you to operate the 3D display e g use the space key to switch between different p
193. ium and Combined excluding the demo version installs with a number of anechoic recordings that may be used with the Odeon software without restrictions except for the orchestra recordings For the orchestra recordings in the WaveSignals Orchestra folder special restrictions apply Customer acknowledges that the anechoic recordings are the sole property of TKK Helsinki University of Technology Customer acknowledges the right to use the recordings for internal use only and the right to make one copy for archival and backup purposes Customer agrees not to modify or remove and not to tamper with or disable any automated display performance or execution of any credits references or notices without the prior written consent of TKK Helsinki University of Technology Customer agrees not to copy modify adapt combine publish rent lease sell distribute the recordings or sublicense or otherwise transfer the sublicense If the anechoic recordings are used in the Customer s work in such a way that an ordinary reasonable user familiar with the recordings would be likely to recognize it Customer agrees to include the following notice in the resulting work Derived from anechoic symphony orchestra recordings by Jukka Patynen and Tapio Lokki Helsinki University of Technology and licensed from Odeon A S L GENERAL This Agreement constitutes the entire agreement between you and Odeon A S concerning the ODEON product If any provision of
194. l time streaming convolution binaural auralisation for headphone playback Select job number 1 in the jJobtist and click the Streaming convolution Dutton This will open the Streaming convolution dialog Select the voice Sabine Short file in the Source signal field this is an anechoic recording of voice stored in a Windows Wave file residing in the directory set in the Options Program setup Auralisation Wave signal file Directory ODEON will start convolving the selected signal file with the selected Binaural Room Impulse Response BRIR in this case the BRIR for job 1 Listen to the output over headphones to benefit from the binaural quality of the auralisation The real time auralisation facility allows auralisation with two simultaneous channels e g simulating the left as well as the right part of an orchestra using a stereo recording as input signal also the input from the soundcard may be used directly for auralisation that is on most computers this is possible if the windows play and record controls have been correctly setup Please press Fi from within the Streaming Convolution display to learn more about operating the options available Before leaving this example you may want to try the Listen to input signal option Listen to a stereo setup The next example will demonstrate how to set up a classic stereo setup with a receiver position and two loudspeaker positions To run this example you need to have a stereo recording sto
195. lable from the Toolbar dropdown menu Setup for print outs and graphics available from the options Program Setup Menu item Export of calculated data in ASCII text format for use in a spreadsheet or other post processing Ja 33 2 3 Short guided tour Basics edition Run the ODEON application You will find the ODEON program at the windows Menu Start Program files ODEON ODEON Execute the program and begin the tour Slopen a room model to work on Select the Open a room mode button to select a room The room files containing the geometries for ODEON carry the extension par or sur for compatibility with previous versions of ODEON and is plain ASCII text files following the format outlined in chapter 0 For this guided tour select the room model named eExample par Ee DView Have a look at the room Whenever ODEON loads a room it is displayed in a 3Dview This allows you to investigate the geometry and check it for errors etc Several facilities are available in the 3pview e g rotation zooming highlighting of selected surfaces and corner numbers etc Press F1 to get overview of the facilities and their use Having assigned a room this is a good time to get familiar with the MDI concept Multiple Documents Interface At this point the title bar of the 3pview will be blue or some other colour indicating that this is the active window Being the active window the 3pview menu item is added to the menu bar next to the Tool
196. layback Calculation of these impulse responses are based on the Ambisonics technique which is covered in Gerzon 1992 Bamford 1995 Malham 2005 Furse Most of the ODEON specific steps involved in the generation of these filters are similar to those used for generation of BRIR s there are however two differences HRRF s are not used in this calculation which is aimed at loudspeaker representation where the listener will receive reflections from own head and torso The other difference is that reflections are added with random phase 6 9 Calculation method for Reflector Coverage 25000 rays are send out from the selected source if the rays hit one of the surfaces defined as reflector surfaces at the Define reflector surfaces menu a Cross is painted where the reflected rays hits the room surfaces Note that the value of the Transition order is taken into account if it is zero and the Lambert scattering is active the chosen reflectors will exhibit a degree of scattered reflection corresponding to their scattering coefficients Sound from line and surface sources will always reflect scattered if the Lambert scattering is on 6 85 6 86 7 Calculated Room Acoustical parameters This chapter will shortly describe the derivation of energy parameters for Single Point Multi Point and Grid response calculations for the Industrial edition only EDT T SPL SPL and STI are available All the parameters are derived on the assumption that t
197. layers to make them invisible in the extrusion modeller but deactivated invisible layers will still be loaded into ODEON The current layer ticked as Current is the one that new objects are created in By checking Move all layers on layer it is possible to multiple surface in one operation It is possible to change the layer of an extrusion surface in the surface editor allowing you to group Surfaces on one layer prior to moving them 3 47 Modelling a chair Odeon extrusion modeller version 3 0 C Users Claus Documents Odeon filer Rooms oes Office inventory OES File Edit Help 7 20 1 30 ho h s50 h s0 h 70 Modeling plane g YZ estica cross sechon D xY Horizontal XZ Verica ength Giid and snap options Snap to ond Ortho sna Honzontal V Grid spacing on Snap see 025 0 25 Metres J Snap to existing cocedinates Lock H and V sn Sutlace edilo Sutace Lay 209 R8O 4 ws Gos oss 2 Eas og i O j Vest miror at 0 009 Mewes Hor ontal tsccie Minor at 0 000 a Point edtor E j140 p 50 j1 0 ee Poir x Y Extrusion Surface x Y 1 00 metres Point input Locked Mouse Drag Selection Scroll RMB Zoom Alt LMB Select Point C X The easiest way to model a chair like the one in the left Figure is to simply enter the same data as displayed in the screenshot of the Extrusion Modeler in the right Figure however a few tricks may be found in the description below If modelling a room in the XY Modell
198. lected surface e Assigning wall Type allowing either calculation Of Transmission through walls or a Normal Exterior Or Fractional Surface property Select the field at the surface and enter the wall type using the mouse e Repeat wall Type Select surfaces for which you want to repeat wall type by holding down shift and use the arrows and repeat wall type with ctri v e Quick Estimate for fast evaluation of reverberation times and listing of summarized absorption areas while assigning materials etc 4 63 e Add Edit Delete a material Four buttons allow you to create new materials or to edit existing ones in the material library The material editor available assists in mixing different materials into one It is also possible to edit materials directly in the material library file e Find surface or Material type Three buttons makes it easier to find a certain surface in the material list or material in the material library The surface search material button for finding material in the library and the toggle interior exterior aNd the layer button for finding an appropriate list of surfaces to edit e Toggle between Global and Local Material Library switches between the Global material library and Local material library e Remove extreme absorption removes absorption coefficients below 0 05 and above 0 95 from the materials in the surface list This should be used if there is doubt whether the absorption is estimated correctly Because th
199. ling that it starts at z 10 and ends at z 15 Modelling an array of surfaces Each extrusion surface has a set of array properties associated with it N Dist Ny dist Nz Dist one set for each of the three main orientations in the room These properties can be found in the Surface editor and define how many times the surface should be repeated in each of the main directions and the distances between the repetitions This feature is typically used in order to create a number of columns beams tables or chairs with a regular spacing When editing an array surface e g modifying a point all the repetitions of the surface will be changed accordingly BExploding an array of surfaces If individual changes are needed the arrayed surface must be exploded Once this operation has been carried out the surfaces in the arrayed surface has been turned into individual Surfaces which can be modified surface by surfaces e g delete some of them It is not possible to perform the reverse of the explode operation so before exploding an arrayed Surface make sure all operations common to the surfaces in the array have been carried out Define Layers For later management of acoustics materials inside ODEON the Extrusion modeller has layers This allow you to assign materials to all surfaces on one layer very fast in the Material list in ODEON Create layer with a name and colour in the layer box above the surface editor You can deactivate
200. lmost self explaining those are the classic textbook examples built from 1 2 4 and 8 sources These sources utilize the omni sos directivity pattern for all their transducers The four sources are all conventional arrays which have been assembled inside the ODEON Array source editor and exported from there Only trick is that the Invert phase Option has been applied to half of the transducers in the Dipol Quadropol and Octopol arrays in order to get the special behavior of those source types The Dipol_Domain_Frequency xm file is essential identical to the bDipol xmi and will give same results when used inside ODEON but this file has been defined using Domain Frequency which is the option that can be used when defining beam steered arrays 12 135 Attributes Array Source Coerion 5 veiy _ gt C sain Z _ CoordSys CoordSys a Qr N Se A lt gt Figure E1 Tree structure for the Array source node The Domain Data nodes are described separately in figure E2 i Y Domain Frequency Domain Octave Domain Frequency Domain Octave EQ Figure E2 Tree structure with the details of the Domain Data node This note comes in two versions depending on weather Domain Octave or Domain Frequency 12 136 Figure E3 Images of the Mono Dipol Quadropol and Octopol directivity patterns installed with Odeon Auditorium and Combined as viewed in the
201. lumn and should never exceed O dB The recording level corresponds to the recording level on a tape recorder If you wish to compare different simulations you should use the same recording level Creating multi channel auralisation is by nature a little complicated and you should get familiar with one channel simulations before using this feature the mixer Multi channel simulations can be created using the mixer in the auralisation display the two rightmost tables The mixer allows you to mix together up to 300 one channel simulations from the Convolve BRIR and Signal file table The simulations can only be mixed together if they e use the same receiver position Point Response Receiver e use the same orientation Receiver towards source To check this scroll through the cConvolve BRIR and Signal file table and view the receiver column Rec and the Receiver towards source point which is displayed as a red cross in the corresponding 3D display Extended Auralisation examples with complete orchestras ne Installed with ODEON 10 are a number of auralisation setups where entire orchestras have been modelled for auralisation in a concert hall and in an opera The installation includes music pieces of Beethoven 21 channels Bruckner 47 channels Mahler 39 channels and Mozart 11 channels To listen to these auralisations e Open one of the rooms in the Orchestra folder e g C Rooms Orchestra ComptonVerneyOpera par e
202. ly image source method to the late ray radiosity method In special cases you may want to alter the parameters to conduct special investigations E g to investigate a high order echo problem you may want to increase the Transition order to get the reflections displayed in the Single point response reflectogram display Auditorium and Combined editions only However this will rarely result in better calculation results for the room acoustical parameters In such cases create an extra copy of the room using the Files Copy files Menu and conduct the special investigations on the copy The Transition order applies only to point sources Current recommendation is to 2 for most rooms For rooms that are heavily packed with various fittings or rooms where no or few image sources are visible from the receivers a lower Transition order Of o Or 1 may be used If a Transition order Of zero is selected then point responses will be calculated using ray tracing ray radiosity only which has better robustness to cases where the wave front is cut into small pieces e g by apertures in the room a situation which is not handled elegantly by the Image source method Number of early rays Job calculations only The Number of early rays iS Normally best left for ODEON to decide ODEON will estimate a Number of early rays to use in order to detect important early reflections Image sources based on the number and size of surfaces the dimensions of the room as well as the
203. m or translation in the 3DView Model appears in a strange position on the screen and zoom translation does not work as expected This problem is probably caused by some small invisible and irrelevant surface s located at odd position s in the imported model Solution 1 Try importing the geometry once again with some of the entities unchecked turned off it may be that some of the entities such as 3ppPoLy or the like were not intended to be surfaces Solution 2 Removing the unwanted surface e In the 3DView turn on the Modelling options M shortcut look out for odd positioned points e Move the mouse cursor to the position of the odd point read one of these point numbers e Click the ODEONEditor icon to open the par file remove the point and try to reload the room by clicking the ODEON icon in the Editor Now ODEON will hopefully report an error stating a surface is referencing the point which no longer exists e Remove that surface along with ALL the points it is referencing out comment them e Reload the room Problem with display of coordinate system The blue coordinate system looks odd or behaves strangely Solution If the Origo is situated in a point far away from the geometry the coordinate system may not display properly when projection is turned on in that case turn off the projection using the P shortcut In order to fully solve the problem the position of the origo should be altered as described in the ex
204. mal separator to use internally in ODEON may also be selected from the OptionsiProgram settingslOther settings Entry 2 18 Define a line source Combined edition Click the New line source button to open the line source editor Enter the values x 4 metres y 2 metres z 2 metres Length 2 metres and Azimuth 135 Finally set the Overall Gain tO 65 dB TO Save the new source just close th Line source Editor and confirm 8 Define a multi surface source Combined edition Click the New multi surface source button to open the multi surface source editor Select Surface 2001 End wall behind podium for this source and click the Invert normal button or shortcut ctri 1 to make the multi source radiate into the room a surface in a multi surface source can radiate energy from one of its two sides or from both its sides Finally set the overall gain to 65 dB TO save the new source just close the multi surface source Editor and confirm fd Surface source Combined edition The facilities of the Surface source are fully included in the multi surface source the Surface source iS Only available for backwards compatibility 2 Define a receiver Click the New receiver button to open the Receiver editor Enter the values x 18 metres y 5 metres and z 3 metres To save the new source just close the Receiver Editor and confirm Define other receivers at x y Z 12 3 2 2 x Y Z 8 7 1 5 x y Z 21 1
205. map of room acoustical parameters if a grid has been specified from the Define grid Menu Setup a Single point response and run it e Optionally Select source number 1 as the Receiver towards source for each of the jobs 1 4 Notice how the blue cross changes into red in the Source Receiver View indicating that it has been selected as orientation of the receiver for the selected job e Select receiver number 1 as the Single Point receiver for job 1 2 3 and 4 e Activate source 1 in job one source 2 in job two source 3 in job three and all three sources in job four You can see which sources are active in a selected job by looking at the 3D Source Receiver View e Click the Run all button in the local toolbar at the right side to run the jobs and the four Single Point response responses will be calculated View Single point response Select job number 1 in the job List and click the view Single Point response button when the calculations have ended to see the results You will find seven tab sheets available in the single Point Response window displaying room acoustical parameters energy curves Reflection density reflectograms 3D reflection paths and Binaural Room Impulse Response filters BRIR You can view results for each of the four jobs by first selecting the job in the Job List then clicking the view Single Point response button To learn more about the results and options available from the Single Point response Window ple
206. menu Context sensitive help Context sensitive help is available using the F1 shortcut key throughout the program The help includes description of the facilities available in a particular window suggestions on the choice of calculation parameters hints on the evaluation of calculation results etc Answers to questions which go on a specific window are found in the context sensitive help rather than in this paper manual Saving data and maintaining consistent results The ODEON program automatically saves the user entered data such as sources and materials with the room Whenever data need to be defined in order to carry out calculations ODEON will prompt whether to accept or discard changes If the changes are accepted ODEON will automatically erase results that are no longer valid ensuring that results are always consistent with data entered When you close a window data is automatically saved upon your acceptance so as a general rule there is no Save buttons available in ODEON dialogs 2 17 2 1 Short guided tour Combined and Auditorium editions Onun the ODEON application You will find the ODEON program at the Windows Menu StartlAll ProgramslOdeon Odeon Execute the program and begin the tour Open a room model to work on Click the Open a room model button to select a room Room files containing the geometries for ODEON carry the extension par or sur for compatibility with previous version of ODEON and are
207. method IS Set tO Lambert The scattering coefficient can be assigned values between O and 1 see section 6 5 Table 1 With the suggested scattering coefficients it is assumed that Diffraction surfaces and Oblique Lambert has been enabled in the Room Setup If this is not the case then a minimum scattering coefficient of 0 1 is suggested 0 3 may be more appropriate for disproportionate rooms such as class rooms If some details are not modelled in a room then the scattering coefficient may also need to be increased a coffered ceiling where the coffered cells have not been modelled may typically have a value of 0 3 to 0 4 for the mid frequencies around 700 Hz Transparency coefficient semi transparent surfaces A transparency coefficient is assigned to each surface this is a way to make the surface semi transparent This feature may be used for modelling many small surfaces in real rooms E g a reflector panel built from many small surfaces with space in between can be modelled as one large surface having a transparency coefficient of e g 0 5 The transparency coefficient can be assigned values between 0 and 1 e 0 0 is assigned to all solid walls This value should always be assigned to the boundary walls of the room otherwise rays will escape from the model e Very small transparency coefficients should be avoided unless the number of rays is increased substantially Instead consider modelling the surface as solid Using a transparenc
208. mnW 0 3 mTranslate 1 2 0 0 Box 1 lw h tb walls in the room modelling the columns for ColYCnt 1 NumColY MReset MTranslate L NumColX 1 w 2 ColYCnt W NumColY 1 0 for ColXCnt 1 NumColX NumbOffSet NumbOffSet 8 comment hint setting NumbOffSet to Auto would do the same job Box 1 ColumnW ColumnW hn columns in the room MTranslate L NumColX 1 0 0 end end HHH Using hybrid statements and coordinate manipulation The following example demonstrates an example on how to use the hybrid statements Cylinder2 and Dome2 as well as the coordinate manipulations which are essential to the use of the hybrid statements This example is a rather complex one so the main parts of the file is explained below Line 3 7 Defining constants Line 8 9 Inserting the cylindrical wall which needs a rotation of 90 around the Z axis Line 11 The foot points of the cylindrical wall which is temporarily stored in PlistA are stored in Plisto for later use definition of the floor Line 12 13 Inserting the dome shaped ceiling The Z rotation has already been set to 90 when the wall was created Line 14 18 Setting the coordinate manipulation for the ceiling and creating the ceiling Line 19 Resetting the coordinate manipulation to work in absolute coordinates Line 20 23 Creating Wall floor point Line 24 25 Defining floor using the cylinder points stored in Plisto Line 28 29 Defining side walls using symmetric modelling Line 30 31 Defin
209. mparison to the wavelength For practical room models surfaces are not infinitely large and ODEON is to some degree able to take into account the limited size of surfaces in calculations using the Reflection Based Scattering method see section 6 4 Still ODEON is a high frequency model so Surfaces should be kept reasonably large don t use more surfaces than needed in order to mimic the geometry modelling a lot of very small surfaces to achieve high geometrical fidelity will not improve quality of results but it will increase calculation time It is difficult to put concrete limits on the size of surfaces which should be used there will always be a need for Small surfaces to fill in awkward corners of the geometry but a rule of thumb may be to keep surface dimensions larger than one wavelength at the mid frequencies one wavelength at 3 40 1000 Hz is approximately 0 34 metres It should be possible to model most concert halls with a surface count of say in between 100 and 2000 surfaces Curved surfaces All surfaces in ODEON must be almost planar so curved surfaces have to be approximated by dividing them into plane sections The question of how finely to subdivide depends on the type of curved surface and how important the surface is Convex curves naturally disperse sound energy so if the surface is in an exposed position e g the end of a balcony near the stage one should avoid for example simply replacing a quarter circle wit
210. mprecise source and receiver positions 9 1 Sources of error There are many sources of error in a room acoustical simulation leading to results which are less than perfect within one subjective limen Sometimes this is quite acceptable because we are just interested in rough results at other times we are interested in results as good as possible In any case being aware of the sources of error may help getting the maximum out of ODEON The sources of error or at least some of them are The approximations made in the ODEON calculation algorithms Inappropriate calculation parameters Imprecise material absorption coefficients Imprecise material scattering coefficients 9 97 e Not accurate or optimal geometry definition for use in ODEON e Not accurate measured reference data to which simulations are compared Approximations made by ODEON It should be kept in mind that algorithms used by software such as ODEON are only a rough representation of the real world In particular the effect of wave phenomena are only to a limited extend included in the calculations There is very little to do with this fact for you the user except to remember that small rooms and rooms with small surfaces are not simulated at high precision Optimum calculation parameters A number of calculation parameters can be specified in ODEON These settings may reflect expected reverberation time a particular shape of the room or a trade of between calculati
211. mpulse response Detection of Noise Floor Most of the impulse response recordings whether recorded directly or obtained using the Sweep method come with a noisy tail due to the ambient background noise and noise of the transmission line involved PC sound card cables and microphone This noisy tail Should be removed before deriving the decay curve and the ISO 3382 room acoustic parameters The ODEON measurement system utilizes a modification of the algorithm by Lundeby for automatically detecting the noise floor and truncating the impulse response at an appropriate time Lundeby 1995 Detection of Direct Sound An ideal impulse response according to geometrical acoustics Kuttruff 1973 would consist of an ensemble of Dirac impulses with appropriate delays and strengths The ideal direct sound from a source should be a perfect Dirac impulse too arriving at a time equivalent to the distance between the source and the receiver However in reality the direct sound and all the other reflections are not perfect Dirac impulses In fact each reflection consists of an onset and some decay As the frequency gets lower the decay of a reflection may overlap with the onset of a subsequent reflection In the derivation of many of the ISO 3382 parameters it is vital to capture the amount of early energy correctly ODEON uses advanced algorithms for successfully detecting the energy from the direct sound and discriminating it from the following reflections
212. mulas are listed and where you may even enter new formulas It is worth to notice that parameters that rely on the E term assumes that time a and b are well defined however this is not the case when there are no direct sight between source and receiver This does make results questionable in simulations as well as in real measurements when direct sight between source and receiver is not present Cso Clarity E C loog Fe dB 8 Q co Dso Definition T Centre time SPL Sound Pressure Level SPL 10log Ey dB The value of SPL becomes equal to the value of G which is the total level re to the level the source produces at 10 m in free field as defined in ISO 3382 1 2009 when an OMNI directional source type and a power of 31 dB Octave band is selected from within the appropriate Point Source Editor LFgo Lateral Energy Fraction E cos f Lk E39 The LFgo parameter has a high correlation with the apparent source width ASW as shown in Bradley amp Soulodre 1995 Lj Average Nioo Lj Average 10log 2 gt gt E cos GB dB Ni 254z t 80 1 Lj Average was known as LG80 in earlier versions of Odeon Only available in Odeon Auditorium and Combined 7 88 The calculated value of Lj Average is according to ISO 3382 1 2009 a source with an OMNI directional source type and a power of 31 dB Octave band is selected from within the appropriate Point Source Editor T
213. n a door hole or the surfaces being made of different materials provides the phase shifts which results in diffraction Therefore it may be reasonable to assume that the boundary walls have a minimum depth of say 10 cm in order to account for such phase shifts Boundary Furniture Interior Margin Figure 6 5 Ground plan of a room with the interior marin marked as a dashed green line Surfaces between the boundary and the interior margin provide low scattering at low frequencies while surfaces inside the interior margin provide high scattering throughout the whole frequency range 6 80 The typical depth of geometry s wall construction should be specified in the Interior margin in the room setup ODEON will use this number in order to distinguish between interior and boundary surfaces Once the margin has been entered and the room setup dialog has been closed the 3DView will display surfaces which are considered to be interior in a greenish colour while the exterior is displayed in black Diffraction from the exterior will be calculated taking into account that diffraction is limited towards the lowest frequencies because of limited depth of the wall constructions Limitations In special cases the Reflection Based Scattering Coefficient may overestimate the scattering provided by small surfaces which are only fractions of a bigger whole e g small surfaces being part of a curved wall or dome Such surfaces should not cause diffraction due to
214. n diffraction When no direct sound is received from a point source at a receiver position ODEON will try to detect a one or two point diffraction path using the methods suggested by Pierce in Diffraction of sound around corners and over wide barriers Pierce 1974 By only calculating the diffracted contribution when the point source is not visible the contribution can be added to the impulse response without considering the phase interaction between direct sound and the diffracted component just like the reflections are added to the impulse response Only diffraction from one edge of the diffracting object is taken into account the one with the shortest path length The edge of diffraction is considered infinitely long More information and validation is found in Rindel Nielsen amp Christensen 2009 By using the algorithms by Pierce rather than less complicated ones ODEON is capable of handling more complicated objects than the single surface screen e g objects such as book Shelves the corner in e g a L shaped room and buildings out doors or diffraction over a balcony front edge or over the edge in an orchestra pit Estimating diffraction points around objects In order to calculate diffraction it is essential that the diffraction path is established In rooms with just moderate complexity it becomes virtually impossible for the user to describe which Surface edges will act as diffracting edges and therefore ODEON has a built
215. n for the lack of energy at the end of the response which is caused by the backwards Schroeder s integration 12 116 Decay Curves all bands Here the corrected energy decay curves E Corrected are displayed for all bands on the same graph You can enable disable the different octave bands in the right side menu Energy parameters All calculated room acoustic parameters are displayed in a table of the same format as that for the single and multi point responses see section 2 1 Parameter curves The room acoustic parameters are displayed in bar graphs You can scroll among the different parameters by using the Left and Right arrow keys in the keyboard Inserting measured room acoustics parameters into a multi point response If a room model has been loaded into ODEON then it is possible to insert the room acoustics parameters derived from a measurement file which has been opened with the Load Impulse Response Use the Add measured parameters INS Shortcut Or Add measured parameters and close Ctri 1NS Shortcut available from the Measured response Menu and specify appropriate job and receiver number in the dialog that appears Once parameters has been added you may view them in the mutti point response al with the given job number and if the receiver number has been specified in the Source receiver list available from the JobList e g together with simulation results see section 2 1 Even if no simulations have been carried out
216. n of receivers receiver grids different kind of sources and the presentation of results Section 2 1 is intended for the auditorium and Combined editions Section 2 2 is intended for the Industrial edition while section 2 3 givesan overview of the Basics edition If you are new to ODEON chapter 2 is a must Chapter 3 covers geometry modelling New releases of ODEON often include new facilities which can speed up the modelling process as well as tools for verification of geometries Some of the facilities are a plug in for Google Sketchup extensive support for import of CAD models in the axf as well as the 3ds 3D Studio format and a stand alone drawing program for modelling of so called extrusion models Tools for verification of room models are also covered in this chapter With improved support for 3 party tools for geometry modelling knowledge about ODEON parametric modelling language is becoming of less importance The advanced user will find that the description of the par format has been moved to appendix E The format features support for symmetric and semi symmetric rooms use of constants variables counters loops etc and can be useful when studying geometrical parameters such as angle of reflectors etc As all geometry also imported ones are stored in the par format it is possible to add features described in terms of parameters to an imported geometry if familiar with this format Chapter 4 deals with the materials to assig
217. n short terms the BRIR is a two channel filter through which a mono signal passes from the sound source s to the left and the right ear entrance of the listener receiver Using convolution techniques to convolve a mono signal with the BRIR a binaural signal is obtained which when played back over headphones should give the same listening experience as would be obtained in the real room Mixing such binaural signals created with different source positions and signals but with the same receiver position and orientation multi channel simulations are possible e g simulating a stereo setup background noise versus loudspeaker announcements or singer versus orchestra k l istening to Binaural Room Impulse Responses As mentioned above the basis of binaural auralisation in ODEON is the BRIR s which are calculated as a part of the Single Point Response ONCE a Single point response iS Calculated it is possible to play the BRIR clicking the Play Single Point BRR Dutton The BRIR may give a first clue as to how the room sounds and it also allows some evaluation of the quality of the calculated point response e g whether to use a higher Number of late rays iN the Room setup Although the BRIR may sound a little rough it may work quite realistic when convolved with a signal less transient than an ideal Dirac delta function can be google d To get a more realistic presentation of a BRIR as it would sound in the real world you might want to
218. n to the surfaces of the rooms absorption scattering and transparency coefficients as well as transmission data Special materials that may speed up the modelling process and how to manage the material library are also covered in this chapter Chapter 5 deals with the auralisation options in ODEON auditorium and Combined the hardware requirements how to publish calculated sound examples on the Internet or on audio CD s etc Chapter 6 introduces the calculation principles used in ODEON giving an idea on the capabilities and limitations the simulation part of the program Chapter 7 describes important calculated room acoustic parameters available in ODEON how they are calculated and how to interpret the results Chapter 8 describes the various calculation parameters available in the program Most of the parameters are automatically set to reasonable values by ODEON however for special cases you may need to adjust some of the calculation parameters Chapter 9 is the discussion on quality of results and how to achieve good results This chapter may be relevant once familiar with the program 1 4 Chapter 10 describes how to extend the library of directivity patterns available for point sources and the use of directivity patterns in the common Loudspeaker Format CLF Chapter 11 introduces the line array sources discussing some basic principles behind array source design Chapter 12 presents the integrated impulse response measuring syst
219. nd Strength the system set up should be calibrated Two calibration methods are available from the Tools Calibrate measurements menu in ODEON that follow the ISO 3382 1 standard Diffuse Field Calibration This should be carried out in a room with long reverberation time and diffuse field preferable a reverberation chamber A group of source receiver combinations is required Two source positions and three receiver positions are probably enough The impulse response for each combination should be recorded and saved Afterwards the files can be loaded using 12 117 Tools Calibrate measurements Diffuse field calibration YOU Should select and load all impulse responses obtained for the same calibration at once use the Ctrl key and mouse in the Open calibration files menu when displayed so that ODEON will calibrate the level according to the average of the values The volume of the reverberant room must be stated Free Field Calibration Ideally this should be carried out in an anechoic room but in many cases it can be carried out in a relatively dry room The receiver should be placed close to the source and the impulse response should be recorded ODEON will try to capture the very early part of the response corresponding to the direct sound According to the distance between the source and the receiver and their heights from the floor the arrival time of the 1 reflection is calculated so that the impulse response is truncated at this place I
220. ng Menu to locate your image file e Double click on your desired origo in the drawing as requested could coincide with an intersection between a horizontal and a vertical module line e Double click at a point having some horizontal distance from the origo as requested could be another vertical module line e Enter the distance between the two points e g distance between vertical module lines e If the drawing is very dark this may be disturbing use the File Make background drawing lighter to lighten the drawing This can be repeated The drawing has now been scaled and is fixed to the drawing canvas when scrolling the drawing canvas or zooming the drawing will adjust appropriately If not satisfied with your scaling of the drawing repeat the process above 3 45 O prawing an extrusion surface Left click the mouse at the positions where the points in the surface are desired if no points and lines are generated then you need to bring the current surface in edit mode using the Insert or Esc Shortcut or by double clicking a point in the surface Once all points in the surface have been defined finish the current extrusion surface by starting a new one using the cti a Shortcut or pressing the Insert Or Esc Shortcut To assign a drawing depth x y or z and an extrusion dx dy or dz select the surface in the Surface editor table where it can also be specified whether the extrusion surface should have a bottom and a top and a De
221. ngle will be valid for version 9 x e g 9 1 9 2 9 21 or whichever versions are released before the next full release number e g ODEON 11 22 The software for updating versions in between the full version numbers can be obtained free of charge from www odeon dk Update to full version number In order to update to the most recent full version the dongle must be updated Once updated it allows running the previous versions from version 9 1 and up The software update can be obtained from www odeon dk updates Update User name For copy protection your user name and country is embedded in the dongle If you should wish to you can change your user name by checking the box Update user name the user name can only be updated separately from the other updates When you send the request file to sales odeon dk you should write the user name you wish in the email Upgrade option only relevant if edition is Basics Industrial or Auditorium Upgrade current Basics In case your current edition of ODEON is ODEON Basics Industrial or Auditorium edition it is possible to request ODEON Industrial ODEON to Combined edition Auditorium or ODEON Combined In case your current edition is ODEON Industrial or ODEON Auditorium it is possible to request ODEON Combined It is not possible to upgrade from ODEON Industrial to ODEON Auditorium nor from a restricted licence to a full commercial licence Time license only relevant if the current version is
222. nnel Left speaker playing left signal IN Convolve BRIR and Signal file table Setup Conv no 2 Row number 2 e Select a stereo signal file e g MyStereoSignal in the signal file Column e Select channel 1 to select the left channel of the signal in the channel column e Select job number 5 in the job no column to simulate the left channel being played through the left loudspeaker In a stereo wave file the first channel is always the left channel and the second channel is always the right channel 2 23 e Adjust the Rcd Lev Recording level to 40 dB or use the overall recording level available in the Auralisation setup Binaural settings this setting is effective on all convolutions Right speaker playing right signal IN Convolve BRIR and Signal file table Setup Conv no 3 ROW number 3 e Select the same signal file as above e g MyStereoSignal in the signal file Column e Select channel 2 to select the right channel of the signal in the channel column e Select job number 6 in the job no column to simulate the right channel being played through the right loudspeaker e Adjust the rca Lev Recording level to 40 daB Mixing signals So far we have setup two mono simulations one playing the left channel and another one playing the right channel of a stereo signal To finish the stereo setup we need to mix the two binaural signals together The binaural mixer is in the right part of the auralisation display If you are using
223. nt edition is Basics Industrial OF Auditorium by requesting a remote licence upgrade Your wishes for update or upgrade could be a combination of the above 4 points which can be fulfilled by generating a remote request file and following the steps described below Remote License Update or Upgrade is divided into four steps 1 Generate a license request file and send it to sales odeon dk 2 You will receive a mail with the license file when your update or upgrade has been generated 3 Download the received license file to your dongle 4 Update your ODEON software installation as needed from the www odeon dk homepage For more info on dongle update please visit www odeon dk dongle update Generating remote request file req The steps involved in Remote request are Epc the following amp Up q k 1 Attach your ODEON dongle to the Update to most resent version of Odeon USB port on the PC Update user name must be supplied seperatly 2 Run the ODEON program Time license 3 Check what your current license Requested update type includes usi ng the Tools License No update to time license information menu entry ee eee ecibas 4 Generate your license request file using the Tools Generate Remote Update Remove time limitation Request fie Menu entry this will display the shown dialog 5 Email the generated request file e g User2005_Dongle102009 req tO sales odeon dk ELZ Once your ODEON dealer has
224. nted for easy identification of the surfaces Could be something like Main floor Example on multi surface containing 5 sub surfaces MSurf 1 5 Steps on a stair 5544 gt 5534 5112 gt 5122 5111 gt 5101 5212 gt 5222 5211 gt 5201 5312 gt 5322 5311 gt 5301 5412 gt 5422 5411 gt 5401 5512 gt 5522 Elevation surface 12 151 Use The ElevSurf statement to define a series of vertical surfaces from a series of perimeter points plus an elevation height The perimeter points are typically defined using the MPt statement The syntax of ElevSurf is ElevSurf FirstSurfaceNumber gt lt FirstPointNumber gt lt SectionsInElevSurf gt lt Height gt lt Optional name gt Example on use of the MPt and ElevSurf statements First the perimeter points point 1 to 23 at the floor level of an office environment are described using the MPt statement Then the elevation surface is created from these points creating the perimeter walls of the office with a constant height of 2 7 metres Finally the floor and ceiling is created using the Surf statement 0 00 110 00 120 00 130 00 140 00 metres Perimeter points at the floor level Example file MPt and ElevSurf Par Demonstrates the use of MPt multi point Surf Surface and ElevSurf Elevation surface statements In this example the X coordinates are made in absolute values whereas the Y coordinates in most cases are in or de creased using the or options To create a closed ElevSurf that is the
225. nvolved and mixed files from the auralisation display using the surround sound hardware 2 25 Trouble shooting surround playback There are a few reasons that we know of why the playback of surround files may fail the most obvious not mentioned here e Make sure that headphones are disconnected If the headphones have their own separate connection then the loudspeaker output may be disconnected when the headphones are connected e If Windows Media Player iS not the default program for playback of wave files then the Surround files may not play unless the software selected for default playback of wave files is also capable of playing this format The problem may be solved by telling ODEON where the Media Player resides this is done in the oOptions Program setup Auralisation Surround Player field e g type C Program Files Windows Media Player wmplayer exe if this is where the media player resides If you are not aware of the location of the wmplayer exe file then you may locate it using the search facility in Windows found in the start menu Getting further To familiarise further with ODEON you should try to change some of the materials sources etc in the room and make new calculations A suggestion is to try changing the scattering coefficient on surface 2004 Rear wall behind audience from 0 7 to 0 05 and listen to the change in sound quality echo problems Create a copy of the room using the File Copy files option then make
226. o short source receiver distance Source Receiver distance Point response calculations made in ODEON are to be compared with point response measurements and as such the ISO 3382 1 2009 standard should be followed 9 99 To obtain good estimates of reverberation time the minimum source receiver distance should be used in order to avoid strong influence from the direct sound The minimum source receiver distance according to ISO 3382 1 is V d 2 m CSI where V is the volume of the room m C is the speed of sound m s T is an estimate of the expected reverberation time s Thus for a typical concert hall a source receiver distance less than 10 metres should be avoided in order to get good predictions measurements of the reverberation time Minimum distance from the receiver to the closest surface If a receiver is placed very close to a surface then results will be sensitive to the actual position of the secondary sources generated by ODEON s late ray method If such a secondary source happens to be very close to the receiver e g 1 to 10 centimetres this may produce a spurious spike on the decay curve resulting in unreliable predictions of the reverberation time indeed if the distance is zero then in principle a contribution being infinitely large would be generated To avoid this problem it is recommended that distances to surfaces are kept greater than say 0 3 to 0 5 metres Anyway for measurements it is for o
227. o the surface in the surface file if given any name Area Lists the calculated area for each surface 4 3 Manage material library and material list Material Toolbar Some of the functions available at the local toolbar as well as from the toolbar dropdown menu allows you to manage the global and local material library and surface properties in the Surface list Osp 4 lT MCE AOE eS e Assign Material assigns the material selected in the material list to the surface s selected in the surface list e Global Replacement replaces all appearances of the material assigned to the selected surface in the surface list with the material selected in the material list This is useful if you wish to replace all materials of one type with another type e Assign Material for all surfaces assigns the material selected in the material list to all the surfaces in the room or in the selected layer e Assigning Scattering coefficient is done a little different You simply select the field at the surface and enter the scattering coefficient using the keyboard e Repeat Scattering coefficient assigns the scattering coefficient last entered in the surface list to the current selected surface e Assigning Transparency coefficients select field at the surface and enter the transparency coefficient directly using the keyboard e Repeat Transparency coefficients assigns the transparency coefficient last entered in the surface list to the current se
228. od of sweep as well as during the Impulse response length period Load Impulse Response You can load an impulse response file in uncompressed wav format by pressing the Load Impulse Response button or by clicking Tools Load Impulse Response SHIFT CTRL L In principle you can load and process any sound wav file in the ODEON measuring system You should be able to see even a music signal in the ODEON measuring system editor but calculated parameters may not make any sense and the room acoustic parameters may not be calculated at all for such a file The larger the file is the longer it will take for ODEON to open it A folder called measurements iS included in the ODEON main folder where all the impulse responses are stored by default High quality Impulse responses can be measured using the sweep facility in ODEON if loudspeaker amplifier microphone etc is available It is also possible to record a handclap the popping of balloon or paperback etc e g using a smart phone if an App has been installed for that and then load the impulse response file into ODEON If a file contains multiple impulse responses such as hand claps ODEON will try to make use of the one providing the best signal to noise ratio S N Figure 12 1 shows a typical impulse response loaded on the Measured Impulse response window 12 115 I Measured response C Odeon12Combined Measurements ImpulseResponse wav Capex Raw Impulse response at 1000Hz Raw decay c
229. of the Sub bands are centered around the full octave band centre frequency in order best to simulate the energy in each octave band If N is odd e g 5 then these frequencies will coincide with ISO centre frequencies Be aware though that the centre frequencies used will differ if an even number e g 6 is used Getting the voltage and energy right Values are in tension V The values should be reduced by a factor which compensates for the NumberOfSubBands N used if N sub bands are used then the re and Img attributes of each node ws 1 should be multiplied by a factor If there were 6 sub nodes in each band and Re 1 15534266201273234 and Img 0 0 for each of them then the equivalent voltage for one sub band representing the total power in that band would be 1 15534266201273234xSaqrt 6 2 83 v 2 83 V is the standard voltage for which sensitivity at 1 metre is given for loudspeakers so with this setting it will reproduce the sensitivity values at a distance of 1 metre se the Dipol_Domain_Frequency xml Sample 2 83 V may seem like an arbitrary value but it is generally agreed upon as standard voltage this is the voltage at which an 8Q 12 142 speaker deliver 1W The reason why the industry has moved from 1W to 2 83V Loudspeakers rarely have a frequency linear impedance of 89 whereas an amplifier is actually fairly capable of supplying constant voltage Position node Attributes x 1 Y 2 Z 0 324 Position of So
230. of the sample having the highest value in the resultant wave file this value should not be confused with loudness or RMS 2 24 Auralisation on loudspeakers It is possible to create auralisation files for playback on a surround sound system The operation of surround sound auralisation is more or less a repetition of the process just described however there are different hardware requirements and a loudspeaker rig must be defined before ODEON can calculate a surround file which is suited for the surround setup available Hardware requirements for loudspeaker auralisation In order to play the surround sound files which can be generated by ODEON a suitable soundcard such as a 4 1 5 1 or 7 1 Surround soundcard must be installed on the computer and connected to a matching loudspeaker system The soundcard must also be setup correctly in order to recognize which loudspeakers system it is currently connected to in the relevant software application which comes with the soundcard Defining the speaker rig In order to create surround sound output enter the Auralisation setup and check the create 2D surround sound impulse response Secondly click the Define speaker rig Dutton in order to define the positions of your loudspeakers If you have a common surround soundcard then click the button for the Speaker system which best resembles your system e g a 5 1 system It is possible to fine tune the positions of the loudspeakers in the Speaker list table
231. olution After completion of the response calculation early decay time and the reverberation time are calculated according to ISO 3382 1 2009 e The Reverberation time T39 is calculated from the slope of the backward integrated octave band curves The slope of the decay curve is determined from the slope of the best fit linear regression line between 5 and 35 dB obtained from the backward integrated decay curve e Early Decay Time EDT is obtained from the initial 10 dB drop of the backward integrated decay curve Sound Pressure Level Cso D gt s0 LFso STearlyr STiate and STiotal The energy of each reflection is added to the appropriate terms in the formulas for all the energy parameters according to its time and direction of arrival After the response calculation Cgo Clarity Ds 9 Definition Centre Time SPL Sound Pressure Level LFgo Lateral Energy Fraction STearny STiate ANd STiotay are derived In the following formulae E is the sum of energy contributions between time a and time b after the direct sound time t is the end of the calculated response and t is for the reflection 7 87 arriving at time t the angle between the incident direction and the axis passing through the two ears of a listener Only the few most common of the parameters that are available in ODEON are listed here in fact you may also look up the definitions of parameters from within the Room Acoustic Parameter list in ODEON where the for
232. ometry Once the geometry has been imported this change may be made as follows Investigate the coordinates of the front edge of the stage 1 Turn on the modelling options in the 3DvView shortcut M and move the mouse in order to investigate the corner s coordinates 2 If pressing the Ctrl key while Left clicking the mouse then the data for the closest corner is copied to the clipboard the data text can be pasted into ODEON s editor using the Ctrl V shortcut 3 54 Pasted corner data from the 3DView Pt 248 10 500 5 90000 24 00000 for a left point on the stage Pt 247 10 500 5 90000 24 00000 for a right point on the stage We may want to locate Origo at the front of the stage This can be done using the Mtranslate statement in the geometry file in order to move the mid point average of the two points above of the stage to 0 0 0 open the par file clicking the ODEON editor icon then just after the sign type MTranslate 10 54 10 5 2 5 9 5 9 2 24424 2 At the end of the file just before the sign type MReset in order to make the coordinate system neutral this is desirable when adding new surfaces to the geometry Click the ODEON icon inside the editor in order to save the modified geometry and reload it into ODEON Other coordinate manipulations to the geometry may be desirable in particular the CoordSys statement described in section 0 may be useful Trouble shooting Problem with zoo
233. on speed and accuracy Number of Late rays ODEON by default specifies a suggested Number of late rays to be used in point response calculations This number is derived taking into account the aspect ratio of the room as well as the size and number of surfaces in the geometry In short this means that ODEON will suggest more rays for very long room with many surfaces than for a basically cubic room with few surfaces The suggested number of rays will be sufficient for many rooms however in some cases more rays may be needed in order to obtain good results in particular in rooms with 1 Strong decoupling effects 2 Very uneven distribution of the absorption in the room Ad 1 If a dry room is coupled to a reverberant room then more rays may be needed in order to estimate the coupling effect well An example could be a foyer or a corridor coupled to a classroom If the room where the receiver is located is only coupled to the room where the source is located through a small opening then more rays are also needed Ad 2 In some rooms the reverberant field in the x y and z dimensions may be very different An example of this could be a room where all absorption is located on the ceiling while all other surfaces are hard Another example could be an open air theatre where the ceiling is modelled as 100 absorbing In particular if surfaces are all orthogonal while having different materials in the x y and z dimensions of the room and if l
234. on type For each radiated ray a random point or origin is chosen at the line or surface source From this point a ray is send out in a random direction and two types of radiation can be chosen Lambert and Spherical When Lambert is chosen for the radiation the strength of each ray is proportional to the cosine of the angle between its direction and the normal Practically rays radiated parallel to the surface have zero strength Whereas rays perpendicular to the surface carry the maximum of the energy Spherical radiation introduces uniform strength to the rays regardless of their direction Lambert radiation is preferable for ordinary surface sources such as noise emission from machinery Spherical radiation is recommended when several point sources are modeled as a surfaces source instead of each one individually e g many people distributed over a large canteen hall Spherical radiation is also a good option for modelling traffic noise which can be regarded as a dense array of vehicles acting as individual point sources s Figure 6 9 Lambert left and spherical right types of radiation applicable to line and surfaces sources 6 8 Processing reflection data for auralisation in Single Point Response A typical point response calculation in ODEON includes some 100 000 to 1 000 000 reflections per source receiver The reflections are calculated in terms of time of arrival strength in 8 octave bands and angle of incidence
235. one becomes large If Oblique Lambert was implemented as described without any further steps this would lead to an energy loss because part of the Lambert balloon is radiating energy out of the room In order to compensate for this the directivity pattern has to be scaled with a factor which accounts for the lost energy If the angle is zero the factor is one and if the angle is 90 the factor becomes its maximum of two because half of the balloon is outside the room Factors for angles between 0 and 90 have been found using numerical integration Oblique Lambert attenuation factors Correction coefficient Oblique angle Figure 6 7 Correction factor for Oblique Lambert When the oblique angle is zero Oblique Lambert corresponds to traditional Lambert and the correction coefficient is one When the oblique angle is 90 corresponding to grazing incidence on a smooth surface the correction factor reaches its maximum of two A last remark on Oblique Lambert is that it can include frequency depending scattering at virtually no computational cost This part of the algorithm does not involve any ray tracing which tends to be the heavy computational part in room acoustics prediction only the orientation of the Oblique Lambert source has to be recalculated for each frequency of interest in order to model scattering as a function of frequency 6 82 6 6 Diffraction over screens and round objects Scree
236. ossible to design a sound radiation that is asymmetric and directed off the horizontal axis see the example in fig 11 7 This can be used to create a very uniform sound level over an extended audience area 2H SH 1DOD He gt DDH DDH J D He Figure 11 7 The radiation in octave bands from 250 Hz to 8 kHz for a line array with 7 units The time delay is 0 1 ms per unit and the level increases by 2 dB per unit from bottom to top 11 5 Using the equalizer In addition to the general equalizer for the array there are equalizer options for each transducer This may be used for fine adjustments or to turn off some transducers at some frequencies E g if you want to use a shorter array at the high frequencies you can enter a high attenuation of the transducers in question 11 6 Bringing the array into the room The position of a line source in a room is similar to that for a simple point source but with some extra options 11 111 e If the transducer coordinate system is Absolute it means that the x y z coordinates of the array indicate the position of the transducer with relative coordinates 0 O 0 if any there need not be a transducer in this position but all transducer coordinates are relative to this point e If the transducer coordinate system is Relative hanging it means that the x y Z coordinates of the array indicate the position of the transducer in the top of the array and the coordinates of the other
237. ould occur on one line Comment lines must begin with a colon a semicolon or an asterisk When only horizontal and vertical polar plots are known POLAR The first non comment line of the file should start with the word POLAR In the polar case there are four lines of data for each frequency band The first four lines are for 63 Hz the next four for 125 Hz and so on For a given frequency the first and last values must agree on all four lines since all the polar plots meet at the front and back polar axe The first line of a group of four is the upward vertical polar plot as seen from in front of the source 12 o clock plot Then comes the left horizontal plot 9 o clock plot downward vertical plot 6 o clock plot and finally the right horizontal plot 3 o clock plot As a minimum there must be 1 4 8 lines in a polar input file Elliptical interpolation When ODEON translates the polar input file it has to interpolate values between the four polar planes given in the input data This is done using elliptical interpolation independently for each frequency band creating the 8 x 4 plots missing between the four input plots An example PolarOmnidat on the polar input format can be found in the DirFiles So8_ASCII_input_file_samples directory created at the installation of ODEON When the complete directivity characteristics are known FULL The first non comment line of the file should start with the word FULL In t
238. ow scattering properties on the surfaces are used then more rays should be used More rays needed There are no way of telling if more rays are needed for a certain calculation but to get an idea whether a room has strong decoupling effects you may try to run the Global Estimate calculation If e Global Estimate Stabilizes slowly e The Global decay curve make sudden jumps like steps on a stair e The Global decay show hanging curve effect this could be an indication that more rays are needed Let the Global Estimate run until the decay curve seems stable then use say 1 10 1 times the number of rays used in the Global estimate to specify the number of rays to be used in the calculation of the point responses specified in the room setup Transition order The Transition order applies only to point sources Current recommendation is to 2 for most rooms For rooms that are heavily packed with various fittings or rooms where no or few image sources are visible from the receivers a lower Transition order Of o Or 1 May be used 9 98 Materials absorption data Wrong or imprecise absorption data are probably one of the most common sources of error in room acoustic simulations This may be due to lack of precession in the measurements or limitations to the measurement method itself of the absorption data or because the material construction assumed in the simulations are really based on guesswork in any case it is a good idea to
239. plain text files following the specifications outlined in chapter 0 For this guided tour select the room model named Example par Ea 3D View Have a look at the room Whenever ODEON loads a room it is displayed in a 3pDview This allows you to investigate the geometry and check it for errors etc Several facilities are available in the 3pview e g rotation zooming highlighting selected surfaces and corner numbers etc Hit the Fi shortcut to get an overview of the facilities and their use Having assigned a room this is a good time to get familiar with the MDI concept Multiple Document Interface At this point the title bar of the 3Dview will be bright blue or some other colour indicating this is the active window Being the active window the 3Dview menu item is added to the menu bar next to the toolbar dropdown menu You can operate the functions of the window using this menu or the shortcut keys displayed in the menu qs Define sources and receivers Before any calculation can be carried out by ODEON at least one source will have to be defined Also a receiver will have to be defined in order to calculate a point response In this guided tour we shall define point line and multi surface sources although only the point source is relevant to this auditorium type of room Finally we define a receiver Click the sSource receiver list button at the toolbar to open the Source receiver list from which sources and discrete receivers are defin
240. plication may emit the message SketchUp is not responding while it is in fact still working on creating the par file normally it only takes a few seconds but in some extreme cases it may take hours 3 42 The models created in SketchUp and exported by su20pdEon are inherently compatible with the requirements set by ODEON Plane surfaces No repeated points No surfaces without area Multi loop surfaces are converted into single loop surfaces Layer support Automatic explosion of blocks and components Unique surface numbers Surface properties assigned in ODEON such as materials surface sources reflectors and grid surfaces are preserved when the model is re modeled in SU and re exported for ODEON In version 11 and later the Google Sketchup file skp file is automatically copied with an ODEON project when using the File Copy files menu from within Odeon 3 43 ODEON Extrusion Modeller A small modelling program the ODEON Extrusion Modeller is included with ODEON The program is found in the Windows start menu along with the ODEON program It can also be launched from within the ODEON editor The Extrusion modeller allows modelling so called extruded geometries in a graphic environment or in other words to draw geometries using the mouse An extruded surface is a flat 2D outline drawn at a specified drawing depth the third coordinate and with an extrusion height When assigning an extrusion height to the 2D outline
241. ponent is reduced by a factor 1 s The edge scattering coefficient is defined to be 0 5 if the reflection occurs at the edge of a surface saying that half of the energy is scattered by the edge and the other half is reflected from the Surface area If the reflection point is far from the edge the edge scattering becomes zero initial investigations suggests that edge scattering can be assumed to zero when the distance to the edge is greater than approximately one wave length therefore we define the edge scattering coefficient as O for dogge X COS O gt e J a d4 X COS OX 0 501 edge COSC X SF for dage COSO lt E c As can be seen scattering caused by diffraction is a function of a number of parameters some of which are not known before the actual calculation takes place An example is that oblique angles of incidence lead to increased scattering whereas parallel walls lead to low scattering and sometimes flutter echoes Another example is indicated by the characteristic distance a if source or receiver is close to a surface this surface may provide a specular reflection even if its small on the other hand if far away it will only provide scattered sound Sa 71 6 79 fw Log frequency Figure 6 4 Energy reflected from a free suspended surface given the dimensions I w At high frequencies the surface reflects energy specularily red at low frequencies energy Is assumed to be scattered blue fw is the upper specular cu
242. ppears when using the toggle button Alt T from within the JobList Offline convolution for flexible Auralisation In the left part of the auralisation display mono signals are convolved with impulse responses in the right part of the auralisation display such convolved signals may be mixed together in order to create multi channel simulations The Auralisation results may be either two channel Signals binaural which should be listened to through headphones or multi channel signals to be played through a surround system The mono input signal is selected in terms of a signal file and a channel in that file In a stereo signal file channel 1 is the left channel signal channel 2 is the right channel signal and average is the average signal of the channels included in the file A Signal file is typically 1 channel mono or 2 channel stereo but may in principle contain many channels 2 27 The impulse response is selected in the Job no column and refers to the Single Point Response With that job number Once the impulse response has been selected the point through which the receiver is oriented is displayed in the corresponding 3D display and the used receiver position is displayed in the table in the auralisation display The recording level may have to be adjusted in order to get a good dynamic range or on the other hand to avoid overload The output level achieved when convolution has been carried out is displayed in the rightmost co
243. ral Reflections in Concert Halls The Derivation of a Physical Measure Journal of Sound and Vibration 77 pp 211 232 Beranek L L 1962 Music Acoustics and Architecture New York John Wiley Beranek L L 1996 Concert and opera halls how they sound Acoustical Society of America Beranek L L 2004 Concert halls and opera houses music acoustics and architecture Acoustical Society of America Beranek L L amp Hidaka T 1998 Sound absorption in concet halls by seats occupied and unoccupied and by the hall s interior surfaces J Acoust Soc Am 104 3169 3177 Bobran H W 1973 Handbuch der Bauphysik in German Berlin Verlag Ulstein Bork I 2000 A Comparison of Room Simulation Software The 2nd Round Robin on Room Acoustical Computer Simulation Acta Acustica 86 943 956 Bork I 2005 Report on the 3rd Round Robin on Room Acoustical Computer Simulation Part II Calculations Acta Acoustica United with Acoustica 91 753 763 Bradley J S 1986 Predictors of speech intelligibility in rooms J Acoust Soc Am 80 837 845 Bradley J S amp Soulodre G A 1995 Objective measures of listener envelopment J Acoust Soc Am 98 2590 2595 Christensen C L amp Rindel J H 2011 Diffusion in concert halls analysed as a function of time during the decay process Proceedings of the Institute of Acoustics Vol 33 Pt 2 pp 98 105 Dublin Christensen C L Nielsen G B
244. re hit very often then carry greater weight in the overall mean absorption coefficient of the room Surfaces which are not detected at all in the ray tracing process are left out of all calculations and surfaces which are hit on both sides are included twice in the calculation As a result the estimated reverberation time corresponds to the sub volume in which the selected source is located Note however that if a part of the area of a surface which is present in the sub volume is located outside that sub volume e g if two sub volumes share the same floor surface then area and surface estimates for the Statistical calculations may not be entirely correct In that case it is possible to set a volume manually The classical mean absorption coefficient is given by Sa rs A where S and amp are the area and absorption coefficient of the i room surface respectively The modified mean absorption coefficient as experienced by the particles is gt HG l pA where H is the number of hits on the i room surface a In ODEON both of these mean absorption coefficients are inserted in the Sabine and Eyring formulae to calculate reverberation times the classical values are labelled Sabine and Eyring and the values using the modified mean absorption coefficient are labelled Modified Sabine and Modified Eyring The mean absorption coefficients used for the Arau Puchades formula are derived in similar ways except that s
245. received your request file an invoice is processed and sent to you When the invoice has been paid an encrypted license file is e mailed to you and this file has to be downloaded into your dongle for a license upgrade see below 1 15 Updating the dongle downloading license file cif to dongle Extract the license update file from e mail to your hard disk e g to your desktop Attach your ODEON dongle to the USB port on the PC Run the ODEON program Use the Tools Download license update to dongle Menu entry Select the file using the Select license update file cif dialog e g select User2005_Dongle102009_ODEON Industrial_V5__Restricted_Oh cif ie ae a Update installation When the license has been downloaded to your dongle you can find and install the new version or edition from the webpage www odeon dk updates You may choose to uninstall the previous version before installation We recommend that you keep a safety copy of the installation file e g if you at some point want to reinstall the downloaded version The window below shows all the update options that may be available whether all these options will be displayed available depends on the license currently stored in your dongle Update option Update to most recent version When a license of ODEON has been purchased for one of ODEON version of ODEON it is valid for the full version number If the license was purchased for ODEON 9 1 then license stored in the do
246. rection t10 Snell s law is the law of Billiard saying that the reflected angle equals the angle of incidence 6 76 Often the resulting scatter coefficient may be in the range of say 5 to 20 and in this case rays will be reflected in directions which differ just slightly from the specular one but this is enough to avoid artefacts due to simple geometrical reflection pattern Incident lt Specular weight 1 s on Ze Resulting ty _ Scattered weight s K gA g Figure 6 2 Vector based scattering Reflecting a ray from a surface with a scattering coefficient of 50 results in a reflected direction which is the geometrical average of the specular direction and a random scattered direction Note Scattering is a 3D phenomena but here shown in 2D 6 4 The Reflection Based Scattering coefficient When the reflection based scattering coefficient is activated in the room setup ODEON will do its best in estimating the scattering introduced due to diffraction whether it occurs due to the limited size of surfaces or as edge diffraction When the method is activated the user specified scattering coefficients assigned to the surfaces should only include scattering which occur due to surface roughness diffraction phenomenons are handled by ODEON The Reflection based scattering method combines scattering caused by diffraction due to typical surface dimensions angle of incidence incident path length and ed
247. rectivity pattern and once more from the auralisation signal which inherently includes the same source spectrum please see chapter 5 for further information With the _Nnatural version of the directivity files it is possible to obtain correct equalization of auralisation output while also achieving correct prediction of SPL Therefore the _Natural versions of the directivity files should be used when defining new sources The old versions of the files are kept in old_sos a subdirectory to the pirfiles directory If you wish to use the old directivities in old existing projects then open the Source receiver list and click the Repair broken directivity links button shortcut ctri L See Chapter 10 for more information about sources and directivities Upgrading from versions earlier than version 8 When upgrading from versions earlier than version 8 it is essential to learn about the new methods for handling of scattering Chapter 4 covers the material properties to assign to Surfaces chapter 6 covers the calculation principles including handling of scattering and chapter 8 covers the choice of calculation parameters Major upgrade If performing a major upgrade typically a full version number or more e g from version 8 to version 9 then ODEON will install to a new directory for that version without changing the existing installation If you have no wishes to use the old version of ODEON then it is recommended to uninstall the version s using
248. red on your hard disk aS a windows wave file at a sampling rate of 44100 Hz or to be able to use the soundcard as the input This file which does not need to be an anechoic recording for this demonstration should be residing in the directory set in the Options Program setup Auralisation Wave signal file Directory 4 Enter the Source receiver list Make a copy of the point source source 1 To do this select source 1 in the Source list then press the c shortcut to copy this will open the Point Source Editor with the new source change the Y coordinate to 4 and type Left source in the Description field Following the scheme above create a copy of source 4 change the Y coordinate to 4 metres and type Right source in the Description field Ea Enter the Job list to carry out calculations First activate source number 4 in job 5 and source number 5 in job 6 then select the receiver and point towards which the receiver is oriented For both jobs you will be sitting in receiver position 1 looking towards source 1 therefore select source 1 as the Receiver towards source point and receiver 1 as the Single point receiver for both jobs Source number 1 is not activated in Job 5 or nor 6 we are only using this dummy source as a an aiming point for the receiver You have now set up job 5 left speaker and job 6 right speaker for calculation of the two binaural impulse responses Click the Run All Jobs to carry out the calculations a Two channel re
249. redefined views Finally set the overall gain to 65 aa 65 is just an arbitrary value To save the new source just close the Point source Editor and confirm New sources are by default turned orf therefore it will not be visible in the 3D Edit source display Press the space key to activate the source for the current Job more on Jobs later on Hint Use the Tab Or Shift Tab Shortcuts to move between data fields hefine a line source Click the New line source Dutton to open the Line source editor Enter the values x 2 metres y 2 metres z 2 metres Length 2 metres and azimuth 135 Finally set the overall gain to 65 dB TO Save the new source just close th Line source Editor and confirm 6 Hint Use the Tab or shift Tab keys to move between fields Depending on the language selected on your computer or is used as decimal point The decimal separator to use internally in Odeon may also be selected from the options Program settings Other settings Entry 2 30 98 Define a multi surface source Click the New multi surface source button to open the multi surface source editor Select Surface 2001 End wall behind podium for this source and click the Invert normal button to make the multi source radiate into the room a surface in a multi surface source can radiate energy form one of its two sides or from both its sides Finally set the overall gain to 65 dB TO Save the new source just close the mutti surfac
250. referenced using the statement 100 gt 100 Sections 1 rather than writing each of the sequential points this is not only a faster way to write things it also allows a rapid change to the number of sections in the cylinder by simply changing the N constant Parametric sample a cylinder RevSurfCylinder Par HHH const N 16 const R 15 const H 10 CountPt 100 N 1 R CosD PtCounter 360 N R SinD PtCounter 360 N 0 CountPt 200 N 1 R CosD PtCounter 360 N R SinD PtCounter 360 N H RevSurf 300 100 200 Sections cylinder walls 12 169 Surf 100 Circular floor 100 gt 100 N 1 Surf 2 Circular ceiling 200 gt 200 N 1 HHH Modelling a box shaped room with columns in two dimensions using two level For End constructs When modelling geometries having more than one level of symmetry it is advantageous to use For End constructs This example shows how to model columns in two dimensions in a room using a two level For End construct Each column is created using 8 points and 4 surfaces thus the numbering used by points and surfaces is incremented by 8 each time a column is created This is done by incrementing the predefined variable NumboffSet by eight for each column in order to make surface and point numbers unique The different positions of the points used for each column are obtained USING MTranslate and MReset Parametric sample BoxColumnRoom Par HHH const L 10 const W 4 const H 3 const NumColX 4 const NumColY 3 const Colu
251. remember this and to estimate the size of error on the material data as well as the impact on the simulated results It has been seen that absorption coefficients outside the range 0 05 to 0 9 should be used with care Christensen Nielsen amp Rindel 2008 In the Material list in Odeon there is a button which will limit the range of absorption coefficients assigned to surfaces in a room to a selected range Solution if materials data are uncertain There is really not much to do about the uncertainty of material data if the room does not exist except taking the uncertainty of the materials into account in the design phase If the room does indeed exist and is being modelled in order to evaluate different possible changes it may be a good idea to tweak adjust uncertain materials until the simulated room acoustical parameters fits the measured ones as good as possible Absorption properties in a material library are often by users assumed to be without errors This is far from being the truth For high absorption coefficients and at high frequencies the values are probably quite reliable However low and even mid frequency frequency absorption data and absorption data for hard materials will often have a lack of precision Low frequency absorption At low frequencies the absorption coefficients measured in a reverberation chamber are with limited precision because e There are very few modes available in a reverberation chamber at lowest frequ
252. rement while still in the field to see if it is consistent If not try to make a measurement with a much longer sweep if using the sweep method that is Normally such errors will issue a WARNING message in the titlebar of the measurement window stating the value of XI non linearity parameter being too high In the following examples of good and bad impulse responses are given Impulse response with well defined noise floor Fig 12 3 displays the raw decay curve for a typical impulse response filtered at 1000 Hz The particular impulse response has a well detected noise floor solid blue line with well defined onset and truncation times In the ODEON measuring system the noise floor is automatically calculated individually for each octave band Impulse response with fluctuating noise floor The tail of the impulse response in Fig 12 4 is polluted by a high degree of non flat noise floor full of spikes and hills This can be an indication of presence of strong background noise during the measurement and the signal to noise ratio is unsuffient for the calculation of all room acoustic parameters In such a case it is wise to repeat the measurement under less noisy conditions C Odeoni2Combined Measurements IR_Basement wav Raw decay curve at 1000Hz M E Measured M Noise floor Onset time Truncation time SPL dB MA 0 0 1 0 2 0 3 04 05 06 0 7 0 8 0 9 1 1i 1 2 Ee edt A e E 1 8 1 9 2 Odeon 1985 2011
253. rface the first one containing the numbers given in the ListOfPointNumbers the next surface with 1 added to all the corners in the list etc Of course all the points referred to need to be defined typically this is done using a CountPt definition for each of the corners referred to in the corner list of the CountSurf statement In the above example the points 1000 1004 1100 1104 1200 1204 and 1300 1304 need to be defined 12 154 Sample room files Beams Par BeamBox Par BeamBoxWithWindows Par Revolution surface RevSurf RevSurf must follow the syntax RevSurf lt FirstSurfaceNumber gt lt CurveStartl gt lt CurveStart2 gt lt SectionsInRevSurf gt lt Optional name gt The RevSurf command is typical used together with two CountPt statements to create a revolution Surface using two curves of points The curves must contain the same number of points The RevSurf command will always create a number of surfaces each build from four points lt FirstSurfaceNumber gt A unique number from 1 to 2 147 483647 for identification of first surface in the revolution surface Using the same number but with negative sign defines the surface and its counter part mirrored in the XZ plane Y 0 lt CurveStartl gt First point number in the first revolution curve The curve of points is typically created using the CountPt statement and the curve must contain one more point than number of sections in the RevSurf lt CurveStart2 gt Fir
254. rface cipic ucdavis edu index htm If you have the capability of measuring HRTF s it is possible to import new sets for use with ODEON Scattering Coefficient It has values from O to 1 Defines the portion of energy that is reflected in a diffuse manner from a surface The rest energy is assumed to be reflected in a pure specular manner 12 132 Appendix C Specify Transmission through walls A new feature in ODEON 9 is the ability to handle transmission through walls taking into account multiple transmission paths allowing walls to have a thickness and to have different materials on either side of the transmission wall Y Assigning transmission data Once a Type of a wall has been set to Transmission in the MaterialList it becomes possible to specify transmission data using the Edit transmission data for surface Option shortcut Alt Y This opens a dialog where Reduction indexes can be specified in one third octave bands from 50 Hz to 10 kHz The data can be entered directly or copied from a spreadsheet or from a text file using the common shortcuts Ctrl C and Ctrl v see description below EJ Microsoft Excel Lydisolation eks xls io x 2S File Edit View Insert Format Tools Data Window Help X A2 v fe Light double wall ar A SB Ree Oe SEs SEe SCN Shae SISK Ewes 1 Sound Transmission Loss SD 53 80 100 125 160 200 250 315 400 500 630 S22 2 iLight double wall 14 14 14 17 21 27 32 3 41 45 48 49 2 M 4 gt M Sheeti
255. rial 1 may be used for modelling outdoor situations e g an open roof This is the only material which will stop the rays during ray tracing and no reflections are generated from surfaces assigned this material Editing and extending the Material Library The materials displayed in the left side of the Materials List window resides in an ASCII file called Material Lis This library provided with ODEON may be altered and extended at will by the user using the material editor available from the material list If you should wish to add several materials e g by copying them from some other file this is possible by editing the file using the odwedit editor which is also available from within the Materials list and following the ODEON material format Furtherit is possible to import multiple material from a datasheet from the manufacturer This is further described at www odeon dk acoustic absorption data Special Materials There are three special materials in the library e Material 0 transparent e Material 1 totally absorbent e Material 2 totally reflective Although the material library Material lis may be edited materials 0 1 and 2 must remain as originally defined Data format for materials in Material Li8 The data format for a material in Material Lis is very simple each material is described by two lines ID_Number Descriptive text up to rest of line a63 al25 a250 a500 alk a2k a4k ask ID_Number must be a unique number betw
256. rials that are not in the global material library and that has a number which conflicts with one from the new material library will get a new number at the end of the local room material library If not satisfied with the new global material library it can be replaced with another library under materials in the installed files 4 64 4 65 5 Auralisation Combined and Auditorium editions only Although much effort has been made to make it as easy as possible to use the auralisation capabilities available in ODEON its felt that a separate chapter is needed as this is where all the threads from room acoustics modelling signal processing wave signal files transducers psycho acoustics recording techniques etc meet In the description of auralisation techniques special words are frequently used please refer to appendix B Vocabulary for a short description In this chapter it is assumed that you have tried the short guided tour in chapter 2 1 The basis for auralisation in ODEON is either Binaural Room Impulse Responses BRIR s or Surround sound impulse responses BFormat is also available for the advanced user which can be calculated as part of the Single Point Response iN the Job List if the Auralisation Setup Create binaural filters OF Auralisation Setup Create 2D Surround Impulse Response Option is turned on In this section only the binaural simulation is covered but most of the points also go for surround Auralisation I
257. rnrsnnnrnn 12 115 Load Impulse RESPONSE ccceeceeceeceeceeceeeneeneeneeneeneeneeaeeneeaeeneeneeneeneeneeneeneees 12 115 12 3 Measurement SOU UD sdgxe ctv coranurndireadaetvenuweianedseonramurce read waueeeeredracdeneureets 12 118 12 4 Examples of Impulse RESPONSES ccc ccccccceee cece scene eee e sees eeeeeeeeeeeeeeeeneeeeennaas 12 119 Impulse response with well defined noise flOOF c cece eeeeeeeeeeeeeeeeeeeeeeeeueueueuaaas 12 120 Impulse response with fluctuating noise floor cece ccc cee scence eee e eee e eee eeeeeeeeaaaaees 12 120 Series Of impulse responses cece eeeeeeeteee eee n ene n eee eeeeeeeeeeeeeeseennnanneeeeesesseeeeanaes 12 121 Impulse response with Magnetic feedback cece eeeeeeeeeeee seen ee eeeeeeeeeeeeaaaaees 12 122 Impulse response with distortion at the ENd cc ccccccccccceeeeeeeeeee seen eee eeeeeeeeenaaaaaes 12 125 Impulse response between buildingS ccccecceesseneneeeeeeeeeeeeeeeeessennnanneeesessseeeeeaaens 12 126 Appendix A References cceeeeeeeecccccccccccccccccccccccccscccsscssccscsssscssssssssssssssssssssssssseags 12 128 APE NAD Br VOCIDU Y sag vacances neriay E EE AEE AE EN naarannrairaee ses eens 12 131 Appendix C Specify Transmission through walls ssssassssensnsnnnnnsrnnnsrrnnenrerrnrerrnrerene 12 133 Appendix D Description of XML format for import of array loudspeaker data 12 135 Appendix E Modelling rooms in the ODEON Editor
258. ror line Creating a mirrored copy Uses the current mirror line in order to create a copy of the currently selected surface Create scaled copy of surface Alt Ctri C shortcut As above but a dialog appears allowing input of a scaling factor Create copy of surface Will create a copy of the selected surface The copy is offset slightly from the original one to make it visible iRotating a surface To rotate a surface select the point in the surface around which the surface should be rotated then activate the Rotate dialog using the ctri r shortcut and enter the number of degrees to rotate the surface positive rotation angles are always counter clockwise CCW A surface can not be rotated around a point which is not included in the surface However this trick will do it insert the point of rotation into the surface e Select the surface e Bring it into editing state Esc Or Insert Shortcut e Add the rotation point it is not important where it is inserted in the sequence of points e Rotate the surface e Delete the rotation point from the surface pei shortcut 3 49 looo hoo zoo 2 pain 3 40 po co MC p 00 To rotate a surface around a point which is not included in the surface a Insert a rotation point in the surface b Use the Rotate surface shortcut Ctrl R to activate the rotation dialog and specify the rotation angle in this case 25 degrees finally delete the rotation point from the surface
259. rray imports without problems otherwise load it into the ODEONEdit editor to study the XML code When the file is loaded you have the chance to study the array in various tabs of the Array source editor Viewing and editing XML documents If your program writes data to be imported into ODEON then we refer to it as WRITER ODEON on the other hand is the READER ODEON will normally be the reader but being able to export array data it is a WRITER as well 12 138 When developing export facilities for array loudspeaker data you may need to inspect or manually edit the files XML files can be browsed and edited in simple programs like Notepad the ODEONEdit editor will however perform syntax highlighting The opeonedit editor is installed with ODEON 10 or later including the free demo version Decimal point can be either or in the XML files ODEON will convert the XML files upon import to conform to the regional settings of the PC on which it s running The format is case sensitive therefore it is important that attribute and Node Names are spelled with upper and lower case as defined use one of the examples installed with ODEON and cut and paste directly from there to your code Encoding and formatting of XML documents Encoding should be set to UTF 8 lt xml version 1 0 encoding UTF 8 gt Or in a coding environment XMLDocument Encoding UTF 8 Most parsers should be able to read a number of other encodings t
260. s calculated at an absolute level e Present the auralisation signal over a loudspeaker in the room in which you are sitting e Measure the sound pressure level in the room at the position where you will be sitting when listening to the auralisation and adjust the output level of the loudspeaker amplifier until the measured Laeg corresponds to the calculated level At this point you have a physical reference level which can be used for calibration of you auralisation playback level e Change between playing your auralisation sample over headphones and over the loudspeaker while adjusting the level of the auralisation playback until you are satisfied that the levels are the same This method is somewhat inspired by the old Barkhausen method for measuring loudness level in Phon and should at least in principle allow perfect calibration of the level the resulting level being within one subjective limen Headphones The binaural auralisation results created in ODEON are binaural signals which should be presented over headphones the objective being to reproduce the same sound pressure at the entrance of the ear canals and at the eardrums for that matter of the subject as would be obtained in the real room if it exists Soundcards A sound card is required in order to play back the auralisation results and may also be useful if you wish to transfer anechoic signals to the hard disk As a minimum the sound card should be capable of handling
261. s estimated using Quick Estimate Reverberation and the room volume estimated by Global Estimate ii Crossing surfaces can look odd and hinder clarity in the 3D displays Do not try to include small geometrical details at the first attempt If there are some large Surfaces which are basically plane but contain complex geometrical features e g a coffered ceiling model them at first as simple planes Then first when this room has been made watertight make the necessary alterations to the geometry file The simplified version can also be used in the prediction exercises to give some idea of the effect of the feature in question Examples on parametric modeling This section will give some short examples on the modelling of rooms using the parametric modelling language of ODEON The options in this modelling format are many ranging from typing the model number by number to dedicated programming This section will try to give an idea on how to use the language and its keywords In the default room directory created at the installation of ODEON you may find several other examples on the Par format Four ways to model a box These examples show four ways to model a box shaped room using plain numbers using constants using constants plus symmetric modelling and using the Box statement along with the MTranslate statement In each example the dimensions of the room are W L H 4 6 2 7 Below the box shaped room is modelled using plain
262. s from a SOULCE iccccccccccceee cece eee eee ee eee Ree e Dene enn EE ee EEE EEE SERED EEE EERE ES 6 83 6 8 Processing reflection data for auralisation in Single Point Response 000e ee 6 84 6 9 Calculation method for Reflector Coverage ccc eeccceceeee eens seen eee e ee eeeeeeeeeeeeeenenenees 6 85 7 Calculated Room Acoustical parameterS c cece cece eeeeeeeeeeee seen eeeeeseeeeeaaaaaanes 7 87 8 Calculation Parameters Room Setup and Define Grid ccc cece cece eee e eee eeeeeeeeeeeee 8 93 9 Achieving good resultS ssssssssssssnsssonesrenssnnnennsnsnnsnsnnenrenennnnesnnnennsnennsnrenenrnne 9 97 9 1 Sources of enO onien aa a a a 9 97 Approximations made by ODEON s assssssssssnsnrsnsnrsrrnnrrrnnnrrnnrnrnnenrrnenrrnrnnrrrnnrrrnnrnennr 9 98 Optimum calculation parameters ssssssssssssrrnrsrrnrrnrenenrerenrrrrnnrrrnnrnrnnrnrnnrnrenrnrenne 9 98 Materials absorption Gata ccece cece eeeseeeeeeeeeeeeeseeeeeeeeeeeeeeeeeeseegeeeeeetssaggueeettteaggenes 9 99 Materials scattering COeEPFICIONES cccccccceeeeeeeeeeeeeeseeeeeeeeeeeeeeeeteeeggggueeneeeeesenenegs 9 99 Mea Un MONT eean E decedent hestitnt E E 9 99 Receiver position S ssssssssssssssnssssnssnsnesnssennsnsenessnnssnsnesnsnennsnesnssenneusnnesnnrneensnene 9 99 Source Receiver distance ssssssssssssnrrrnnsnsensnronensnneurnnesnsnssnsnennsnsnnenrenennnnennnnne 9 99 Minimum distance from the receiver to the closest surface
263. scription May be entered The drawing depth and extrusion for each extrusion surface is displayed graphically at the bottom of the application window Editing or correcting an extrusion surface In order to make corrections to an extrusion surface select it in the Surface editor table and bring it into edit mode using the Insert Or Esc Shortcut Once in edit mode it is possible to change coordinates of the points insert or delete points and to move the surface using the mouse operations listed below It is also possible to enter the precise coordinates of points in the Point editor table which list the point in the selected surface so it is an option to draw a sketch using the mouse and then fine tune the coordinates afterwards in the Point editor table Operation on surface Mouse operation Create a new point in selected surface LeftClick mouse Select the point in selected surface which is closest to Mouse pointer Ctrl LeftClick mouse Move closest point in selected surface Ctrl Alt LeftClick mouse Move selected surface Shift LeftClick mouse Move selected surface when its not in edit mode LeftClick mouse Manipulating the viewport The viewport can be manipulated using the shortcuts listed below It is possible to make changes to the view while drawing a surface View operation Mouse operation Scroll drawing area Right mouse button Zoom In Out Alt Left mouse button Snap to grid Snap to grid enables points new points or
264. signals in stereo in a 16 bit resolution at a sampling frequency of 44100 Hz To transfer signals without loss in quality to from a DAT recorder the soundcard Should be equipped with digital input and output and the soundcard should be able to handle a sampling frequency of 48000 Hz It should also be considered whether the card is immune to electromagnetic noise which is always present in a PC and whether its analogue output for headphones is satisfactory For surround auralisation obviously a multi channel surround soundcard is needed along with the necessary loudspeakers and amplifiers Input signals for auralisation anechoic recordings For auralisation you will be using input signals to convolve with the calculated BRIR s Usually the signals will be anechoic signals although it may also be other types of signals e g if you 5 69 are simulating an ordinary stereo setup in a room you will probably be using a commercial stereo recording The input signals to be used with ODEON are stored in uncompressed wave files having the well Known wav extension Most if not all resolutions are supported so files edited by programs such aS CoolEdit OF Adobe Audition Can be used without any conversion being required e 8 16 24 32 bit PCM e 32 bit IEEE Float e 8 16 24 32 bit PCM Extensible tells the number of significant bits e 32 bit IEEE Float Extensible includes some additional info which is not used for input by ODEON To be
265. sions in the rooms and to use high level statements to describe multiple points and Surfaces in a fast and flexible way Before starting your first large modelling project it is a very good idea to read through chapter 3 or at least skim it it will pay off in the end Another way to learn about the modelling language is to study the examples which are installed in the ODEON Rooms Manual samples directory along with the ODEON program open the room s in ODEON then click the Open the ODEON Editor icon on the toolbar in order to study the geometry file Components in the modelling format The basic function of the modelling format is to allow modelling of surfaces in room geometries The surfaces can be modelled point by point surface by surface however it is also possible to make use of symmetry and to create repeated features in a room such as columns using programmatically loops finally it is possible to use hybrid functions which creates points as well as surfaces in terms of shapes such as boxes cylinder and domes Constants variables and counters Constants and variables can be defined and used in the file format It is a good habit to use constants whenever a value is used more than a few times in a file this reduces typing errors and it also makes it easier to make general changes to geometry such as changing the height of a room Mathematical expressions Mathematical expressions can be used to express any real or integer n
266. sssasssssnsssssnnrsrrnnsrrnrenrerrnrerenrsrene 12 145 The ODEON Par modeling format language ssssssssssrssnssrrenrrnnrnrrnrrnrrnrrnrrnrrrrrnn 12 145 Creating a new Par file time saving hints ssssssssssnnnssrnnsnrnnrnrsnenrnrrnnrrrnnsrrnn 12 167 Examples on parametric modeling sssssssssssssssnssnsnssnsrennsssnnesennessenessnnesnsnesnsnene 12 167 Appendix F Mathematical expressions available in the Par modelling format and the Room ACOUSUC Parameter LIST srecne aai an R Ea EnA 12 173 Appendix G Importing geometries compatibility ccc cccccceeee sees seen eens eeeeeeeeeaanaes 12 175 1 Installing and running the program 1 1 Installing and running the program To run ODEON your PC must be running one of the operating systems supported by ODEON 32 bit Windows XP 32 bit Windows Vista 64 bit Windows Vista 32 bit Windows 64 bit Windows 7 32 bit Windows 8 and 64 bit Windows 8 ODEON comes on a CD ROM containing the edition of ODEON purchased Basics Industrial Auditorium or Combined As an alternative you may download the most resent updated version including service updates that has been made since the production of the CD ROM from www odeon dk updates To install the program a Double click on the file with the name of the edition you wish to install e g InstallOdeon12Combined exe to install the program b To run the program the supplied hardware key Rockey 6 Smart R6 Smart must be insert
267. ssumed to be metres however if you prefer to model in another unit this is possible using the Unit statement Check the example below Example modelling in Inches Unit Inches You may choose your unit among the following predefined Metres Centimetres Millimetres Inches Feets and Yards Or if you need a different unit simply type the scaling factor from your unit into metres e g Unit Inches corresponds to Unit 0 0254 The Unit statement may be used more than once in the same par file HHH Unit Inches e g imported model data in inches Unit 0 57634 model data measured on a paper drawing which appeared in an odd unit Unit Metres model data appended in the ODEON editor modelling environment sit is most practical to use metres as the unit when modelling in the ODEON environment then coordinate values will be the same in the Editor as inside the 3D View in ODEON HHH 12 156 CoordSys statement The CoordSys statement is used if you wish to redefine the orientation or the coordinate system in which the geometry was modelled The statement is typically used if the geometry was by accident modelled in an orientation different from the one assumed by ODEON or if it was imported from a CAD drawing where the orientation may also be different To obtain the easiest operation inside ODEON the following orientation should be used using a concert hall as the example e X axis pointing towards the audience
268. st point number in the second revolution curve The curve of points is typically created using the CountPt statement and the curve must contain one more point than the number of sections in the RevSurf The second curve must always contain the same number of points as the first curve lt SectionsInRevSurf gt The number of surfaces to be created by the RevSurf statement If creating a cylinder a number between 12 and 24 is suggested Although it is easy to create many surfaces in a revolution Surface too many small surfaces should be avoided If the FirstSurfaceNumber is 100 and SectionsInRevSurf iS 3 surface 100 101 and 102 will be created lt Optional name gt Optional user defined name for easy identification of the surface e g cylindric wall Example RevSurf 1000 100 200 6 Cylinder creates a revolution surface divided in 6 surfaces surface 1000 1005 This call requires two curves of each 6 1 points to be defined namely point 100 to 106 and point 200 to 206 If the two curves of points define corners in the lower and upper edge of a cylinder a cylinder of 6 sections is created see example room RevSurfCylinder Par Loops using the FOR END construct The For statement must follow the syntaks For lt CounterName gt lt CountFrom gt lt CountTo gt lt CounterName gt Name of counter to be used by the For statement The counter is automatically defined by the For statement and becomes undefined when the loop finish
269. struct in the following way adding a point number at a time for MyCounter 0 10 PList0 100 MyCounter 10 end It is also possible to add a number of points to a point list e g another PList to a PList In the following example PList is assigned the points 100 110 120 130 140 150 160 170 180 190 200 10 11 12 13 15 Plist PlistO 10 gt 13 15 A point list can be referenced in the following way adding point 1 before and 2 after the list in this example Surf Test_surface 1 PListO 2 To reset the list use the statement list O used in this example ResetPList0 Multi Surface MSurf The multi surface MSurf is essentially just a variant of the Surf statement Instead of typing one header line e g Surf 1 A surface name for each surface the header can be shared by multiple Surfaces MSurf lt SurfaceNumber gt lt NumberOfSurfaces gt lt Optional Description gt lt ListOfPointNumbersI gt lt ListOfPointNumbers2 gt lt ListOfPointNumbers3 gt ere lt NumberOfSurfaces gt lines with lists of points describing each surface lt SurfaceNumber gt A unique number from 1 to 2 147 483647 for identification of the surface Using the same number but with a negative sign defines the surface and its counter part mirrored in the XZ plane Y 0 The surface number may be defined using mathematical expressions lt NumberOfSurfaces gt The number of surfaces in the MSurf lt Optional Description gt A string displayed and pri
270. t To learn more about the other parameters available from this page please press Fi LS Global Estimate a reliable method for estimation of reverberation time RUN Global Estimate and let it run until you are satisfied that the decay curve has become stable and then press the Derive results Dutton Note the longest reverberation time The reverberation time differs from the values calculated by Quick Estimate because the room shape and the 2 19 position of absorbing material are taken into account It is important that the impulse response length IN the Room Setup is at least 2 3 of the reverberation time FN Define room acoustic parameters In the room acoustic parameter list Select which acoustic parameters will be calculated in the Single Point response Multipoint response and Grid response It is also possible to create parameters which are not included in the default list if you click the expand tables button so that three tables are displayed ready for advanced editing Ea Calculating point responses in the Job list At this point we are ready to calculate point responses Three different point response calculations are available e Single Point response Offering detailed calculation results and auralisation options for one selected receiver e Multi Point response Offering room acoustical parameters for all the receivers defined in the Receiver list at the Source receiver list e Grid response Offering a calculated grid
271. t of a start gun e g using a smart phone with an App installed that supports recording wave files such applications are available from the relevant application stores for Android as well as IPhones The clapping hands is the source and the phone acts as the receiver microphone The files containing impulse responses can be loaded into ODEON using the Load impulse response button As the energy of a handclap is limited ODEON may not be able to derive energy at all in particular lower frequency bands due to background noise still this may be better than nothing Technical Background High quality measurements using the sweep method The room impulse response measurements in ODEON can be performed using linear and exponential sweep signals which have been judged to be superior in suppressing the background noise leading to a high signal to noise ratio Muller 2001 A sweep is simply a pure sinusoidal signal whose frequency varies in time monotonically The sweep method for measuring impulse responses is the least sensitive method to time variance and distortion and it is expected to work well on most hardware systems ODEON uses sweeps to excite a room and records the response to this signal at a microphone receiver position in real time This sweep response is then deconvolved to give the impulse response between the source and the microphone For this process upward Sweeps are used instead Of downward Meaning that low frequencies
272. t off frequency defined by the shortest dimension of the surface fl is the lower cutoff frequency which is defined by the length of the surface Boundary walls and interior margin As long as surfaces are truly freely suspended surfaces they will act as effective diffusers down to infinitely low frequencies For surfaces which are elements in the boundary of the room such as windows doors paintings blackboards etc one should however not expect these elements to provide effective scattering down to infinitely low frequencies From diffuser theory it is found that typical behaviour is that the effectiveness of a diffuser decreases rapidly below a cut off frequency which can roughly be defined from the depth of the diffuser wall construction being less than half a wave length Two octave bands below the cut off frequency the diffuser is no longer effective At the lowest frequencies however the dimensions of the room will provide some diffraction therefore the dimensions of the reflecting panel as used in the formulae for fi and fy are substituted with the approximate dimensions of the room at the lowest frequencies and a combination of surface and room dimensions are used for frequencies in between high and low frequencies It is worth noticing that it is not only the depth of the wall construction which enables the elements of the wall construction to provide diffraction also angling between the surfaces offsets e g the door being mounted i
273. tation 10 180 counter clockwise rotation around loudspeaker axis is positive Nodes to Orientation Vector Vector node Attributes to Vector Z 0 Is used for defining orientation need not be a unit vector Above is the default orientation of an array or a loudspeaker right turned coordinate system assumed Vector is just another way to specify Azimuth and Elevation not needed if Azimuth and Elevation have been specified defaults to 1 0 0 READER should allow both WRITER should normally just use the one most comfortable CoordSysOffSet node Offset of array coordinate system see ArrayCoordSys Attributes to CoordSysOffSet x 1 Y 0 Z 0 EQ node Overall equalization in dB of the array speaker one value for each octave band Attributes to EQ Octave_31 0 Octave_63 0 Octave_125 0 Octave_250 0 Octave_500 0 Octave_1000 0 Octave_2000 0 Octave_4000 0 Octave_8000 0 Octave_16000 0 ODEON will only make use of 63 to 8000 Hz octaves other bands are ignored by ODEON Any band omitted defaults to O dB Transducer node there should be at least one transducer in an array typically there will be more Transducer all nodes below included Attributes Description A descriptive text Gain 5 Overall in dB per octave band defaults to 0 Balloon Omni So8 Balloon data are stored in a directory known to the reader e g c ODEON9Combined DirFiles The balloon name may
274. ted individually for each reflection as calculations take place s l s d s The formula calculates the fraction of energy which is not specular when both diffraction and Surface roughness is taken into account 1 s denotes the energy which is not diffracted that is energy reflected from the surface area either as specular energy or as surface scattered energy the resulting specular energy fraction from the surface is 1 S 1 S 6 77 S Surface scattering Surface scattering is in the following assumed to be scattering appearing due to random surface roughness This type of Set of scattering coefficients 0 015 0 06 0 25 0 55 E 0 8 gt 0 9 scattering gives rise to scattering which increase with frequency In Figure 6 3 typical frequency functions are shown In ODEON these functions are used in the following way Specify scattering Scattering coefficient coefficients for the middle frequency around 700 Hz average of 500 1000 Hz bands in the materials list then ODEON 63 125 250 500 1000 2000 4000 8000 expands these coefficients into values for Frequency Hz each octave band using interpolation or extrapolation Figure 6 3 Frequency functions for materials with different surface roughness The legend of each scattering coefficient curve denotes the scattering coefficient at 707 Hz At present it has
275. tem 12 1 Introduction Method A measurement system has been integrated into ODEON version 12 so simulated and measured decay curves as well as room acoustic parameters can be done in the same software This allows ODEON to function as a room acoustics simulation as well as a room acoustics measurement program Indeed both measurements and simulations can be displayed side by side at the same time for easy comparison of results as ODEON to a large extend aims at displaying measured and simulated results in similar displays It has been made easy to transfer measured room acoustics parameters to the multi point response displays available from the joblist making it easy to compare measurements and simulations and or to get statistic values for a number of measured receiver positions even if no simulations have been made Two extra buttons have been added in the toolbar in ODEON 1 Measure impulse response By and 2 Load impulse response he buttons which are always active whether or not a room has been assigned The Room Acoustic Parameter List button EY remains always active too in order to make it possible to edit parameters that are displayed in the Load impulse response window there are some limited options in the Industrial edition Sketchy measurements If you are not bringing the full set of measurement equipment PC amplifier loudspeaker etc you can record a hand clap the popping of a balloon or a paper bag or indeed the gunsho
276. ter flexibility and reusability Parametric modelling defining multiple points Use the mPt statement to define a series of points which is typically used in connection with the ElevSurf or ElevSurf2 Statement The syntax must be as follows MPt lt Number gt lt NumberOfPoints gt lt XMathExpressionl gt lt YMathExpressionl1 gt lt ZMathExpressionI gt lt XMathExpression2 gt lt YMathExpression2 gt lt ZMathExpression2 gt NumberOfPoints lines each defining a point in the multi point sequence should follow the MPt statement lt Number gt A unique number from 1 to 2 147 48364 7 for identification of the first point in that multi point sequence lt NumberOfPoints gt The number of points defined by this multipoint statement if the number is 3 then 3 lines should follow each describing the coordinates of a point Example 1 defining point number 100 in x y z 1 1 1 and point number 101 in x y z 2 2 2 MPt 1002 1 0 1 0 1 0 2 0 2 0 2 0 As a special option for multi points it is possible to repeat a coordinate used in the previous point of that multipoint sequence or to repeat the coordinate while adding or subtracting a value from that point 12 149 Example 2 defining point number 100 in x y z 1 1 1 and point number 101 in x y z 1 2 0 MPt 1002 1 1 1 l Defining a series of points using the CountPt statement The CountPt statement must follow the syntax CountPt lt FirstPointNo
277. the audience area can be simplified a lot without compromising the quality of the results in fact using the Suggested method below is likely to produce better results a Model the audience area as audience boxes with a height of approximately 0 8 metres above the audience floor b Assign appropriate absorption material e g ODEON material 11001 4 Yt PA pace c Assign a high scattering coefficient Of DE MIE gt 0 7 to the surfaces of the audience Myo box EZ SS d Position the receivers some 0 4 LOSS metres above the modelled SLL audience box SS An obsolete alternative solution was to model the audience just as a flat absorptive surface on the floor mainly for simplifying the model for computational issues The main problem with this approach was that the absorption area of the room looked smaller since more rays were likely to hit a hard surface like the isles between audience areas than in real life In order to 3 41 compensate for that the same absorptive material had to be assigned to the isles too Nowadays there is no need to follow this approach Modelling audience as a box has been proved to be a very realistic and reliable assumption without affecting the computation cost How to model the podium on stage Same guideline as for the audience area goes here Rather than modelling each step of the podium on stage the podium can be simplified into a few sloped surfaces S
278. the changes to this room model In this way you will have results from both of the rooms present for comparisons Pre calculated Rooms Round Robins At this point you have tried the basic functions in ODEON and may want to view results for more realistic rooms A few pre calculated examples are covered in section 2 3 The examples include rooms which were used in the 2 and 3 Round Robins on Room Acoustic Computer Simulations along with the measured and simulated results Summary of the calculation methods Global Estimation of reverberation time There are two calculation methods for the calculation of global reverberation time built into ODEON The two global estimation methods for reverberation times estimates reverberation time for the complete room with one selected source position Quick estimate Quick estimate is the fast method which is found in the material List This method is based on the Sabine Eyring and Arau Puchades formulas and as such assumes diffuse field conditions Diffuse field cannot be assumed if e Room absorption is unevenly distributed e Room contains de coupling effects e g connected corridors or niches Thus the results given by Quick Estimate Should not be considered to be a final result Even so the method is useful in the initial work on assigning reasonable materials to the surfaces in the room S Global estimate Global estimate IS a More precise method which doesn t make any assumptions about
279. ther reasons recommended to keep distances greater than a quarter of a wavelength i e 1 3 metres at 63 Hz A distance of 1 metre is required by ISO 3382 9 100 10 Directivity patterns for point sources 10 1 Generic point sources Generic point sources such as the OMNI or SEMI directional sources are typically used for calculating the frequency response and parameters characterizing the room acoustics Typically for the generic source is that it is defined mathematically 10 2 Natural point sources With natural sources we refer to sources such as human voice an acoustical instrument or similar Natural sources are typically used for auralisations and or calculation of acoustical parameters that depends on a specific sound power of a natural source E g speech intelligibility of a person or sound pressure level by a smaller machine A recorded signal for auralisation is associated with the directivity pattern of the actual source present during the recording In an auralisation the directivity pattern for natural sources in ODEON is used together ace SD with the recorded frequency spectrum of KD e g a voice and if not handled correctly this will result in auralisation where the overall Be JI frequency response is included not once but twice first time through the directivity pattern which includes the overall frequency of natural source response second time through the recorded source signal which inherently include th
280. tion index itself takes into consideration the wall thickness So for a wall persisting of two parallel surfaces the reduction Index should only be used once To accomplish this it is important that e Transmission type is assigned to both surfaces in the MaterialsList e Same set of reduction indexes are selected on either surface in the Transmission dialog e Double sided wall check mark is selected for both surfaces in the Transmission dialog Most of the above can usually be accomplished if the Update double sided wall upon exit is checked when Transmission data for the first wall is edited It is recommended checking and rechecking the data entered for transmission data before making calculations a check may involve using the 3DBilliard OF 3D Investigate Rays to ensure that walls do in fact transmit sound and that double sided walls has been set up correctly 12 133 0 2 4 6 8 10 12 14 metres 6 metres Path lt m gt 8 50 Refl order colour 0 1 2 3 4 5 6 7 8 9 10 11 gt 12 Time lt ms gt 25 Odeon 1985 2008 Licensed to Odeon A S Dead balls _0 Figure D2 3DBilliard display illustrating Transmission through a double sided wall as can be seen ODEON understands correctly that balls should jump through the wall from one surface to another The principle of calculations is shown in Figure D2 Statistically 10 of the balls rays are transmitted and 90 are reflected However this is compensated for
281. to point 112 and point 200 is equal to point 212 The donut surface is created simply by connecting the inner and outer ring of points into one surface It doesn t matter whether one of the rings are created clock or counter clockwise The surface is created from the following list of points 100 101 102 110 111 112 200 201 202 210 211 212 DonutSurface par HHH Const RI 10 Const R2 15 Const N 12 201 CountPt 100 N I1 R1 CosD 360 PtCounter N R1 SinD 360 PtCounter N 0 CountPt 200 N 1 R2 CosD 360 PtCounter N R2 SinD 360 PtCounter N 0 Surf 100 Donut surface 100 gt 100 N 200 gt 200 N HHH 12 171 The window example shows how a cylindrical window opening is created in ceiling surface The interesting surface in this example is surface 1 the ceiling surface The surface is created from the following list of points 1 100 101 102 103 111 112 1 2 3 4 Ceiling With WindowTube par HHH Const R1 0 75 Const R2 0 5 Const N 12 Ptl1110 Pt21 10 Pt3 1 10 Pt 4 110 CountPt 100 N 1 R1I CosD 360 PtCounter N R1 SinD 360 PtCounter N 0 CountPt 200 N 1 R2 CosD 360 PtCounter N R2 SinD 360 PtCounter N 2 Surf 1 Ceiling 1 100 gt 100 N 1 gt 4 RevSurf 2 100 200 N Window tube Surf 100 Window glass 200 gt 200 N 1 12 172 Appendix F Mathematical expressions available in the Par modelling format and the Room Acoustic Parameter List Constants variables point numbers surface numbers and coordinates ma
282. to the HIDE or the RENDER commands when imported into e g AutoCAD however it is possible to convert POLYLINE s into REGION entities which are visualized correctly as surfaces in some CAD programs if the 3DPoly s are not plane this may not work In some cases it may be desirable to switch this import option off when importing to ODEON as the DXF file may contain such entities which the modeller did not intend to be included in the 3D surface model to be imported the entities may have been modelled for other reasons e g as assisting lines in the modelling phase POLYLINE when the POLYLINE is closed and the elevation height is set to zero This entity is not really a true surface however in some cases it may be used by some CAD programs including AutocAD in order to bypass the limitation of maximum four points in a surface If a geometry which was exported from ODEON to the CAD program is to be imported into ODEON again this option should be on in order to import all 3D data In some cases it may be desirable to switch this option off as the DXF file may contain such entities which the modeller did not intended to be included in the 3D surface model to be imported the entities may have been modelled for other reasons e g as assisting lines in the modelling phase 3DSOLID REGION BODY recognized but not supported These entities are acis solid modelling entities which are not directly supported by ODEON However solid modelling is prob
283. to the interior margin will be reflected in this display when the Room Setup dialog is closed This measure tells ODEON that effective scattering provided by boundary room surfaces should be restricted below a frequency derived from this measure see chapter 6 5 for details To get an idea of our suggestions to this value please look into the geometries supplied with the installation of ODEON whether a value of 10 or 20 centimetres is chosen may not be critical but for rooms with a very jumpy boundary it should be considered to specify this parameter Key diffraction frequency Default is 707 Hz in order to obtain the best result in the mid frequency range for speech and music This is the frequency at which diffraction is calculated for the ray tracing part of calculations All other parts of point response calculations take into account frequency dependent scattering Only in special cases where the focus is on another frequency range should this frequency be changed Scatter coefficients gt x xx handled as uniform scatter From published material on measured scattering coefficients there seems to be a general trend that modest scattering tends to be area based whereas high scattering is better represented by uniform scatter In ODEON small scattering coefficients i e below x xx iS handled either with the Lambert Oblique OF Lambert algorithms whereas scattering coefficients above x xx are handled using uniform scattering Scattering coef
284. transducers are relative to this e If the transducer coordinate system is Relative standing it means that the x y Z coordinates of the array indicate the position of the transducer in the bottom of the array and the coordinates of the other transducers are relative to this e In all three cases it is possible to include an additional offset of the coordinate system For example this can be used with the relative standing position to specify the distance from the centre of the lowest transducer to the physical bottom of the array loudspeaker The direction of the array is controlled from the acoustic centre of the array see fig 11 8 It may be convenient to define a receiver point to be the aiming point or the OpenGL option will let you look into the room from the centre of the array and the aiming point is the centre of the picture the crossing point of the two diagonals will indicate the exact point lka ha Ine See 0 0 0 3 0 5 0 8 1 0 metres 1 0 metres Path lt m gt 0 70 Refl order colour 0 1 2 3 4 5 6 7 8 9 Time lt ms gt 2 Odeon 1985 2009 Licensed to Odeon A S Dead balls 0 Figure 11 8 An array source with 7 units as specified in Table 11 1 The ray tracing in the room acoustic simulations is made from the acoustical centre shown just behind unit T4 The coordinates defining the position of the array refers to the cross on top of the array the hanging option 11 112 12 Measurement Sys
285. ttribute SampleRate is needed e g 44100 Hz OF 48000 Hz Nodes Position Orientation DomainData LAA DomainData node There are two kinds of domain data so far also described in figure E2 If Domain Octave simple octave band equalization is applied to each transducer This can be used for exporting and importing simple array types as they are defined inside ODEON the format being compact it may in some cases even be used for typing data manually into a text file If Domain Frequency then beeming filters are entered as a number of Complex numbers per octave band We suggest that NumberofsubBands an attribute of the ArraySource iS set to 6 Attributes DomainData has no attributes Nodes to DomainData EQ or Octave_31 Octave_63 Octave_125 Octave_250 Octave_500 Octave_i1000 Octave_2000 Octave_4000 Octave_8000 Octave_16000 EQ node EQ node is only present if Domain Fulloctave Attribute of Transducer Attributes to EQ Octave_31 0 Octave_63 0 Octave_125 0 Octave_250 0 Octave_500 0 Octave_1000 0 Octave_2000 0 Octave_4000 0 Octave_8000 0 Octave_16000 0 ODEON will only make use of 63 to 8000 Hz octaves other bands are ignored by ODEON Any band omitted defaults to O dB Octave_31 Octave_63 Octave_125 Octave_250 nodes These nodes are only present if Domain Frequency then a number of Octave nodes are defined each of these Octave nodes have Sub nodes 12 141 Nodes Sub
286. type will usually be preferable for modelling cylindrical ceilings The syntax for Cylinder is Cylinder lt Number gt lt NumberOfSurfaces gt lt Radius gt lt RevAngle gt lt Height gt lt T B N gt lt optional name gt lt Number gt A unique number from 1 to 2 147 483647 for identification of the first point and surface in the Cylinder USing the same number but with negative sign defines the cylinder and its mirrored counterpart in the XZ pane Y 0 A Cylinder will take up several point and surface numbers which must all be unique lt NumberOfSurfaces gt For a full cylindrical room with a revolution angle of 360 around 16 to 24 surfaces are recommended For columns a number between 6 to 8 is recommended lt Radisus gt Radius of the cylinder must always be greater than zero lt Revangle gt Revangle Must be within the range 360 and different from zero If RevAngle is 180 a half cylinder is generated if its 360 a full cylinder is generated Positive revolution angles are defined counter clockwise lt Height gt If the height is less than zero the orientation of the cylinder is inverted If height equals is zero one circular surface is generated Insertion point The insertion point of the cylinder is always the centre of the floor bottom surface Connection points The foot points in Cylinder are stored in PlistA The top points in Cylinder are stored in PListB The example shown was generated
287. udspeaker channel in the specified surround setup The impulse response has the extension surRoundnn wav where nn refers to the relevant job number The convolved files have the extensions convSurRoundAuralnn wav where nn refers to the row in the table conv no and vice versa for the mixed files These files should be playable using the Windows Media Player 5 70 Publishing audible results on the Internet To publish calculated demonstration examples on the Internet it may be useful to convert the result wave files into compressed mp3 files Or wav Mpeg Layer3 files as download times for wave files can be lengthy One minute of compressed stereo signal will depending on the compression rate take up approximately 1 MB If publishing examples make sure that copyrights are not violated You are free to publish examples which are calculated using the anechoic examples supplied with ODEON For the orchestra recordings the conditions as specified in the software license agreement 8 must be observed see p 1 7 Remember to inform the end user to use headphones when listening to the samples Publishing results on an ordinary audio CD If a CD R drive is installed on your PC it is quite easy to transfer the wave result files into an ordinary audio CD most CD R drives comes with the necessary software for this purpose Most people have access to a CD audio player so publishing results on an audio CD makes it easy to send demonstrations to
288. uild yet The aim is to provide the same three dimensional listening experience to the listener as would be achieved in the real room at the given receiver position with the simulated source position s and signals Binaural recording Humans usually listens using two ears This allows us to perceive sound as a 3D phenomenon To create a binaural recording it is not enough to create a two channel recording stereo also the colouration created by diffraction from the human body has to be included This is usually done by using a dummy head with a microphone mounted at the entrance of each ear canal this recording may be recorded using an ordinary stereo recorder but is now refereed to as binaural Binaural recordings are usually played back through headphones to avoid colouration from the room in which it is played as well as avoiding diffraction from the human body to be included twice at the recording and at the playback If one has measured or indeed simulated the BRIR s see below in a room it is possible to simulate a binaural recording BRIR Binaural Room Impulse Response The BRIR is the key to binaural room acoustic auralisation The BRIR is a set of impulse responses detected at the left and right entrance of the ear canals of a dummy head or indeed at blocked entrenches of the ear channels of a living person residing in a room when a sound source or some sound sources has emitted an impulse The BRIR should include
289. ulation results and short calculation time A complete histogram containing both early and late energy contributions is generated and used to derive Early Decay Time and Reverberation Time The other room acoustical parameters are calculated on basis of energy collected in time and angular intervals For surface and line sources a number of secondary sources are placed randomly on the Surface of the source each emitting one ray and radiating a possible contribution to the receiver The rays emitted from these source types generate an independent secondary source each time they are reflected Compared to the calculation principle applied to the point sources one might say that transition order is always zero and that only late energy contributions are collected for these source types or rather that calculations are based on a sort of ray tracing Vector Based Scattering reflecting a Late ray Vector based scattering is an efficient way to include scattering in a ray tracing algorithm The direction of a reflected ray is calculated by adding the specular vector according to Snell s law scaled by a factor 1 s to a scattered vector random direction following the angular Lambert distribution of ideal scattered reflections Sin2 Rindel 1995 which has been scaled by a factorswhere sis the scattering coefficient If s is zero the ray is reflected in the specular direction if it equals 1 then the ray is reflected in a completely random di
290. ulti Point ANd Grid Response results from within the Job lis The results of the simulations are similar to what can be obtained from impulse response measurements in a real room Source types calculation methods Responses from point sources are calculated using a hybrid calculation method where the early reflections are calculated using a mixture of the Image source method and ray tracing and the late reflections are calculated using a special ray tracing process generating secondary sources that radiates energy locally from the surfaces of the walls Responses from line and Surface sources are carried out using the special ray tracing method Energy Reflection order 6 73 The calculations carried out are divided into a two step process a receiver independent part and a receiver dependent part Receiver independent ray tracing The purpose of this process is to find virtual sources that radiate energy into the room Rather than thinking of reflections the idea is so to speak to substitute the room with a number of sources at various positions and delay in space The process is divided in to an early part based on the image source method for point sources and a late part based on a secondary source method ray radiosity Early part finding the image sources Image sources can be found by just taking all combinations of walls up to a given reflection order e g Source Wall1 Wal2 Wal1 Wall3 and so on For simple rooms wit
291. umber in the file e g coordinates constants variables counters point numbers surface numbers etc If you use a value that is not an integer to describe a point or surface number then that value will be rounded to the nearest integer value You may describe coordinates using mathematical expressions like 12 145 Length Sin PI 4 where Length is a user defined constant or variable Mathematical expressions may not contain any SPACE or TAB tabulation characters To get a complete overview of the mathematical functions available please refer to appendix F Points A point is made up from an unique point number and its X Y and Z coordinates Use the Pt MPt and CountPt statements to define points Points can also be defined implicitly using one of the hybrid statements Surfaces A surface is made up from a unique number an optional descriptive text and a number of points connected to one another All the points must be coplanar otherwise the surface cannot be constructed To define surfaces use the Surf MSurf CountSurf ElevSurf ElevSurf2 and RevSurf statements Surfaces may also be defined implicitly using the hybrid statements Hybrid statements Hybrid statements are Box Cylinder Cylinder2 Cone Dome Dome2 and ElevSurf The hybrid statements create the points and surfaces needed to model the specified shape The points and surfaces created must always have unique numbers Coordinate manipulation functions A set o
292. urce of transducer origin given in metres Position defaults to 1 1 1 Orientation node Attributes Azimuth 27 180 around vertical axis counter clockwise is positive Elevation 10 90 up is positive and down is negative Rotation 10 180 counter clockwise rotation around loudspeaker axis is positive Nodes Vector Vector node Attributes X 0 993768018134063 Y 0 0694910287794796 Z 0 0871557402186753 12 143 12 144 Appendix E Modelling rooms in the ODEON Editor The ODEON Par modeling format language Geometry models can be made using the parametric modelling language which is built W in to ODEON The model data are typed into a text file given the file extension Par using the modelling language described below You may use the supplied editor opEoneait to create and edit your text files The ODEON modelling format is not case sensitive so upper and lower case letters can be used as desired A simple modelling example At its simplest but not fastest a floor with the dimensions 4 x 4 metres can be defined as follows using the reserved keywords Pt and Surf in order to define points and surfaces FloorSurface Par HHH Pt Pt Pt Pt Surf 1 HHH Ne AR WN waocrnARS KASS esses A One may choose to model the room point by point and surface by surface as in the example above however for many geometries it will be an advantage to use parameters to describe basic dimen
293. urn on the multi option for the jobs 1 to 4 in order to calculate the point responses for the four receivers you have defined Notice how the active sources are displayed in the 3D Source receiver display as you scroll through the Job list viewing results When the calculation has finished select job number 4 in the job list and click the view multi button to view the multi point response results To learn more about the results and options available in this window press Fi You may also select the page of interest and investigate the dropdown menu which then appears in the top of the program window You can view the Multi point response results for each of the four jobs by first selecting the job in the Job List then clicking the view mutti Point response Dutton 2 335 3D Investigate Rays 3D Investigate Rays ViSualises the ray tracing as it is carried out during any point response calculation By default its calculation parameters are also set up as the parameters used for the multi point response calculations This display is a very valuable tool for debugging of new models e g to detect missing or misplaced surfaces It may also give an impression of what is happening in the calculations e g the effect of the scattering assigned to the surfaces Click the ok button then click the single forward button a few times and note the behaviour of the ray tracing Other facilities in ODEON Apart from the features which have been demonstrat
294. urve at 1000Hz Decay curves at 1000Hz T 30 0 34 seconds Decay curves all bands Energy parameters Parameter curves C Odeon12Combined Measurements ImpulseResponse way Ray Impulse response at 1000Hz2 p x E 2 3 a D time seconds incl filter delay Figure 12 1 The measured response window in ODEON Raw Impulse Response The Raw Impulse Response displays the broadband and filtered pressure impulse response see Fig 12 1 You can switch between different octave band filters by using the up and Down arrow keys on the keyboard A vertical dashed purple line indicates the onset time of the impulse response ODEON detects the strongest peak in a recording whether this is a typical impulse response or any sound file If the recording consists of a series of impulse responses e g hand claps the onset time of the strongest impulse response will be detected A vertical dotted red line indicates the truncation at the noise floor Whenever there is not sufficient signal to noise ratio in the impulse response recording the truncation time cannot be determined safely Instead of the truncation time the estimated end of the response is displayed again by a vertical dotted red line You can zoom in by clicking the left mouse button and dragging towards the lower right corner of the graph In that way a zoom in rectangle is specified between certain values of the horizontal and the vertical axes Releasing the mouse button the r
295. ware soundcards and loudspeakers Windows as well as the native software associated with soundcards are capable of remapping loudspeaker signals that is if the signals are mapped in the first place As an example a 7 1 soundcard may have a program e g SoundBlaster has an application called creative Speaker Settings Which allow you to select the output format to be 5 1 or indeed stereo if that is the layout of your loudspeaker system In the other end of the signal chain the same thing is the case if a 5 1 system is asked to play a mapped 7 1 signal then Windows will remap the Signal in order to match it with the hardware available or rather the hardware which the system is aware of In order to achieve optimum results it is highly recommended that speaker rig defined in ODEON matches that of the physical loudspeaker rig and that the setup of the soundcard is also in agreement with that Calculating surround files If the speakers have been correctly defined you may enter the auralisation setup and calculate the surround results e g click the Run All Jobs Dutton Once calculations have finished an extra button will be available in the toolbar in the right side of the joblist allowing you to toggle between the binaural and surround sound mode if both options were chosen in the Auralisation setup Click the button until the title bar in the jJoblist display surround Mode At this point it should be possible to play impulse responses as well as co
296. with the following code 12 162 CylinderStatement Par HH const N 16 const R 15 const H 10 Cylinder 1000 N R 270 H TB Cylindrical room HHH Hint The cylinder can be made elliptical using the MScale statement The Cylinder2 statement Cylinder2 is a cylinder shell of the calotte type Rather than specifying the radius and revolution angle Cylinder2 is specified in terms of the width and height Cylinder2 is typically used for cylindrical curved ceilings The syntax for Cylinder2 is Cylinder2 lt Number gt lt NumberOfSurfaces gt lt Width gt lt Height gt lt Length gt lt T B N gt lt optional name gt lt Width gt Width is oriented in the X direction on the Figure lt Height gt Height of the cylinder shell is oriented in the Y direction on the Figure and may be positive concave shell as well as negative convex shell Height must be different from zero and less or equal to Y2 Width lt Length gt Length of the cylinder shell is oriented in the Z direction the Figure If Length is negative the orientation is inverted Insertion point The insertion point of Cylinder2 is always foot point of the calotte floor bottom surface Connection points The foot points in Cylinder2 are stored in PlistA The top points in Cylinder2 are stored in PListB The example shown was generated with the following code HH Const N 10 Const W 5 Const H 1 Const L 10 Cylinder2 1 N W H L TB Cylinder calotte HHH Hint The
297. y be defined using mathematical expressions Where integer numbers are expected Counter ranges in for end loops point surface numbers etc the results of mathematical expressions are automatically rounded to the nearest whole number Operation Syntax Example Addition Subtraction 2 5 7 3 1 2 23 6 4 2 2 Multiplication oo t ae 2 o S N a ee a a o ooo Base Exponent Division Power Power Exponent Base Power 3 2 8 Root Index Radicand Root 3 8 2 Round X Round 2 67676 3 Trunc X Trunc 1 7 1 Root Round Truncation Int X Sin X Cos radians Sin O 0 Cos PI 4 0 707106781 186547573 Tan PI 4 1 Cotan 180 0 Sinh Q 0 Cosh 0 1 SinD 90 1 CosD O 1 Sine of an angle in radians Cosine of an angle in radians Tangent of an angle in radians Tan radians Cotan radians Sinh radians Cosh radians SinD radians CosD degrees TanD degrees TanD 45 1 CotanD degrees CotanD 90 0 ArcSin Y ArcSin Sqrt 2 2 180 PI 45 ArcCos X ArcCos Sqrt 2 2 180 PI 45 ArcTan Y ArcTan 1 180 PI 45 ArcTan2 X Y ArcTan2D 1 1 180 PI 45 ArcSinD Y ArcSin Sqrt 2 2 180 PI 45 Cotangent of an angle in radians Hyperbolic Sine of an angle in radians Hyperbolic Cosine of an angle in radians Sine of an angle in degrees Cosine of an angle in degrees Tangent of an angle in degrees Cotangent of an angle in degrees Inverse Sine in radians Inverse Cosine in rad
298. y coefficient greater than zero will cause the Image source method to be discarded for rays hitting such surfaces only relevant for point sources Another problem is that only very few rays will be transmitted making the results on the other side of the surface statistically unreliable e Very large transparency coefficients e g 0 95 should also be avoided Instead consider removing the surface from the model An easy way to do this is to assign Material 0 transparent to the surface The Transparency value should not be used for modelling sound transmission through walls instead use the wall type for this purpose see below HINT If assigning scattering and transparency coefficients between 1 and 100 ODEON will assume that the values are in percent and divide by 100 Type The wall Type can be set tO Normal Exterior Fractional Transmission The type Normal Exterior and Fractional relates to the way Reflection Based Scattering is calculated for sound reflecting from the Surfaces Transmission iS for walls which transmit sound to another room e Normal is the default value which results in default handling of scattering and diffraction taking the Reflection Based Scattering method into account if it has been enabled in the Room setup e Exterior forces a Surface to be handled as an exterior surface even if it was not detected as such by ODEON the result is that less diffraction is applied at the lowest 4 62 frequencies where o
299. y of a line in the par file there The contents following the Debug keyword is evaluated or if it can t be evaluated then echo ed directly to the debug window in ODEON when loading the geometry and it has no effect on the geometry If DebuglsOn is set to FALSE then debug lines are ignored Contents in the Debug strings which can not be evaluated are displayed in quotes Example When loading the following par file into ODEON HHH DeBugIsOn TRUE debug option turned on if DebugIsOn is set to false then Debug lines are ignored const L 6 Debug L debug a single constant const W 4 Debug const W 4 const H 2 7 Debug L W H Debug values of L W and H Box 1 L W H TB Walls floor and ceiling Debug Box 1 L W H TB Walls floor and ceiling Debug a complete line HHH ODEON will create this Debug window as a response Debug window a DebugleUn it TRUE at places in par file thus user defined Debug messages may be displayed in this window In order to prepare the geometry for calculations and skip debug messages the DebuglsUn flag must be FALSE everwhere in the par file Line 4 L 6 Line 6 const Wr 4 4 4 Line 6 L 6 Wwf 4 H 2 FO000000000000032 i 11 Bos 1 1 L 6 We4 H 2 70000000000000032 TB walls floor and ceiling 12 166 Creating a new Par file time saving hints The golden rule when creating a par file to model a room is to think carefully before you start typing For very simple rooms
300. you may benefit from the Multi point response display as it can provide results that related to multiple receivers e g statistics or results according the new ISO 3382 3 standard on open plan offices You can toggle between simulated and measured mode in the multi point response by pressing m Figure 12 2 shows an example of measured and simulated T3 in the multi point response Multi point response parameters job 1 Simulated mode eng Energy parameter curves 1 Energy parameter curves 2 Parameter versus distance Statistics Spatial decay curves STI versus distances Noise control Energy parameters Measured versus Simulated T 30 at 8000 Hz Receiver 2 E Simulated gt lt Measured T 30 s T 30 s 00 E E E 9 wo its f a o rvs w w w m N Ts ita K ig o Distance Frequency Hertz R1 at 10 12m R4 at 12 76 m Q Q tO 63 125 250 4000 8000 2000 Fig 12 2 Simulated and measured reverberation time T3 inside the Auditorium 21 at the Technical University of Denmark The graph on the left shows the values at all receivers for a given octave band while the graph on the right shows the values at all octave bands for a given receiver Press the Up and Down arrows to change frequency Press R to change receiver Calibrate Measurements So far recording and processing of impulse responses have been described without calibration taken into account In order to calculate the Sou

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