Home

A-112

1. MIDI output A 112 Sampler 3 Controls Atten Control attenuates the level of the voltage at input Depending upon the mode this voltage is the audio signal in sampling or effect mode or the wavetable control voltage in wavetable mode Tune The tune control is used to adjust the sampling frequency during record or the pitch tune during playback see table below Exception In wavetable record mode one of the 256 pages is selected with the tune control see following table In this case the sampling frequency defaults to the last frequency that was set prior to switching into wavetable mode System A 100 tune page sampling tune page sampling position appr freq kHz position appr freq kHz 0 0 2 0 6 154 18 5 1 26 2 9 7 179 26 5 2 51 4 2 8 205 38 5 3 77 6 1 9 231 56 2 4 103 8 8 10 255 79 4 5 128 12 7 The data in the table are approximate values DHEP FER iS The voltage generated with the tune control is internally added to the voltage at input 6 This input is normally used to control the pitch of the sampler wavetable oscillator in play mode with an external control voltage following the 1V oct standard e g the A 190 MIDI to CV interface Run LED is used for different monitoring purposes depending upon the mode selected A description of the respective function is given in the corresponding paragraph elsewhere in this
2. Additio nally the current sampling frequency is transmitted 6 MIDI Out The MIDI output transmits MIDI dump information during sample or wave dumps 18 System A 100 5 User Examples The obvious application of the A 112 is the sampling and playback of external sounds or sounds generated with other A 100 modules On top of this the module opens up a huge number of sound experiment possibi lities far too many to be covered in this manual The following examples concentrate on wavetable applications of the module Wavetable Oscillation The wavetable oscillator feature and the loop feature of the A 112 have already been described in chapter 3 Smooth sequencing of the wavetables with an external control voltage requires a certain amount of subtle intuition and additional A 100 modules as it is necessary to control the offset and amplitude of the voltage applied You do then also have the ability though of selecting a specific starting wavetable offset and starting the up down sweep through the waves amplitude at this particular point For the most effective wavetable control we recom mend using the A 129 3 attenuator and offset genera tor see below UOEPFER System A 100 The control voltage range 0 5V corresponds to the 256 tables OV table no 1 5V table no 256 To move from one table to the next one a voltage diffe rence of about 0 02 V 5V 256 is required Example To sweep with
3. Oscillator with two con trol voltages one for the audio frequency pitch tune one for the wavetable number Normally suitable wavetables are generated by a com puter and transferred to the A 112 via MIDI Dump Effect mode Additionally the module offers some effects like De lay Reverse Delay and Pitch Shifter Of course due to the 8 bit resolution these effects are not to be compared however with the results from high end effect devices but should be considered as a free extra gift for strange sounds a Cb A kz rm a 2 m rm I System A 100 Sampler A 112 2 SAMPLER Overview Controls Atten A 112 SAMPLER VC Sampler Wavetable Osc Tune Ps MIDI Out Eff SZ 4 Run e WGRA 6 Dmp CJ Rec Man Trig m MIDI In Trig D owe Switches MJ Norm A u Gate ln pam Audio Out In Outputs PR 9 Run 3 l 0 O Audio a Wave CV In Audio In Wave CV In e CV In CV In eo e Gate In Audio Out MIDI In MIDI Out Attenuator for Audio Wave CV Input Manual control for Sampling fre quency Gate indicator LED overload warning during record manual trigger start button 3 position switches for mode se lection Input for audio signal resp wa vetable control voltage in wa vetable mode pitch control input 1V oct for tuning or sampling frequency Gate input Audio output MIDI input
4. a SysEx dump via MIDI OUT and LED turns on same function as sample dump request via MIDI in iS To trigger a sample dump manually a short high gate level is sufficient It is not neces sary to keep the gate level high e Wave dump mode System A 100 QHEP FER The number of the wavetable is determined by the position of the tune control and the voltage applied to CV input 6 e Delay mode Audio Wave CVln Tune CV Eff Del Norm audio signal sampling fre quency Audio Wave CVIn Tune CV S1 Dmp Wav wave page num 2 ber This mode is very similar to the normal dump mode see above The difference from the normal dump mode is that the data of a single wavetable page of 256 bytes is transferred instead of the complete sampling memory of a bank 12 This mode generates a simple delay The incoming audio signal is delayed and passed to the audio out put iS The memory bank S2 is overwritten in this mode Principle The incoming audio signal is sampled and written into a memory position in bank S2 Before this the old value at this position is transferred to the audio output The number of the memory position is in creased by 1 and the process is repeated When reaching the last memory position the process starts at memory position 1 The last memory position depends upon the length Len see below DHEP FER The length
5. an LFO Triangle output through 64 tables starting with table no 96 i e pas sing through the tables 64 128 the following conditi ons are required An offset voltage of 96 5V 256 1 875V and an attenuation of the LFO signal to 64 5V 256 1 25V peak to peak Using a A 129 3 the offset voltage is adjusted with the offset control and the LFO level with the attenuator control If each of the 64 tables are to be used i e none of the tables is to be skipped there is a maximum frequency that the controlling signal LFO must not exceed Ifthe sampling frequency is 32kHz each wavetable 256 byte takes 8 milliseconds All 64 tables take 512 milliseconds This corresponds to 1 95 Hz LFO fre quency Consequently the frequency of the LFO must be about 2 Hz or less to play each table without skipping This sounds very mathematical and theoreti cal but it is a good idea to understand these facts as some unforeseen things may happen if one ignores these details In practice of course the resulting sound is all that counts Sampler A 112 Sequencer controlled wavetable playback In the patch in fig 6 the Analog Trigger Sequencer A 155 controls the playback of different wavetables step 1 4 5 and 7 The sawtooth output of the LFO patched via offset generator A 129 3 generates the control voltage to sweep through the wavetables This voltage is added to the sequencer voltage post out 2 Thus different ranges of the wavetable mem
6. formats Stereo WAV files are converted to mono before transfer to the A 112 22 System A 100 DHE FER The WAV file format opens up a wide pool of sounds for use with the A 112 You may try out Windows sy stem sounds or modifying sounds with a sample editor program and then re loading back into to the A 112 For the next version of the sample dump loader pro gram we are planning to include the ability to generate sample dump MIDI files iS The latest version of the sample dump loader can be found on our internet home page http www doepfer com for free download QOOEPFER System A 100 Sampler A 112 MPU 401 Portadr EESJO ira gt EJ Creationdate Creationtine User Sanplefrea gt KENEN Code fornat Channels Sanpl Sec Bytes Sec Bytes Sample Bits Sample Datasize YYYYYYYYYY 1 2 Folzr el ayar 1995 fig 7 A 112 sample dump loader 23 A 112 Sampler 7 Patch Sheet The following diagrams of the module can help you recall your own Patches They re designed so that a complete 19 rack of modules will fit onto an A4 sheet of paper Photocopy this page and cut out the pictures of this and your other modules You can then stick them onto another piece of paper and create a diagram of your own system Make multiple copies of your composite diagram to use for remembering good patches and set ups cm lt Draw in patchleads with coloured pens lt Draw or write co
7. of the delay memory is defined by the parameter Len see below The maximum length is the complete sampling memory 64kbyte 65536 bytes With a sampling frequency of 32 kHz this corresponds to 2 seconds delay time The actual delay time is decided by a combination of the length of the delay memory Len and the sampling fre quency Gate low The module is waiting for gate high LED is off The initial sampling frequency is set Gate high The delay mode is started LED turns on Retrigger is active i e a gate transition to low and back to high starts the delay mode again iS Moving from delay mode directly to delay with freeze is not possible To perform this one has to interrupt the delay mode switch to 1 S2 or switch to Len and then select the desired mode By feeding the A 112 output back to its input one obtains a repeat or echo see fig 5 Beware too much feedback leads to an avalanche like effect In this case the feed back component has to be reduced System A 100 Sampler A 112 Audio lt n A Audio W gt Out Feedback fig 5 Echo e Reverse delay mode _ Audio Wave CVIn Tune CV Eff Rev Norm audio signal sampling fre quency This mode is the same as the delay mode but the playback of the delayed signal takes place in reverse iS Memory bank S2 is overwritten in this mode Principle Same as the normal dela
8. the freeze option one simply has to turn the gate to high iS Changing directly to the normal effect without freeze permanently is not possible To per form this one has to interrupt the freeze option switch to 1 S2 or switch to Len and select the desired mode after this e Effect parameter Len Audio Wave CV In O Tune CV Del memory length for Eff Rev Len the effect in que Pit stion In this operation mode the parameter Len is adjusted This value determines the length of the sampling memory in bank S2 used for the effect modes Gate low In this state the Tune control adjusts the Len parameter The resolution for the length is one page 256 bytes The tune knob turned fully to the left ccw position 0 corresponds to one page turned fully to the 15 A 112 Sampler right cw position 10 it corresponds to the whole memory 64 kbyte or 256 pages During the adjust ment of Len with the tune control no external voltage should be applied to the CV input 6 Gate high As soon as the gate goes high the current position of the tune control is used to set the Len value For the different effect modes the following notes also apply Delay Pitch Shift The factory setting is 4 kBytes i e 16 pages This corresponds to a tune control setting of about 0 5 Reverse Delay The factory setting is 64 kBytes i e 256 pages This corresponds to tune c
9. the position of the Tune control and the voltage applied to the CV input The audio input is sampled and 256 bytes are written into the wavetable memory page selected When the last byte of the page i e byte no 256 ofthe page is written record starts again at the first byte of the page This process continues LED on until the gate goes low The record process stops immediately at the present position as soon as the gate goes low You can use this function to sample chosen segments of sound When reaching the last position of the current wa vetable page the number of the next page is defined by the position of the Tune control and the voltage applied to the CV input provided that gate is still high Consequently different pages may be selected during record if the control voltage e g from an ADSR or the position of the tune knob is changed A 112 Sampler In fig 3 the CV input is fed from the sine output of a LFO The sampling frequency is 32kHz the LFO fre quency 21 Hz The resulting wavetable pages are shown in the boxes 251 243 238 N 5V rea N 220 154 128 System A 100 e Wave play mode Audio Wave CVIn Tune CV S1 Play Wav Number of wave sampling fre S2 page quency 51 5V 1 WA U 1 fig 3 wave record m
10. E ee eee d H a ng ee he NE NET a EN Be SS A gece ea EE a Ee a ee ee ee 0 2 Br w Mg Anaa a H 0 40 fig 4 wavetable selection with CV voltage applied to audio wave input System A 100 Sampler A 112 e Normal dump mode Audio Wave CVln Tune CV S1 Dmp Norm 2 In this mode a sample bank 1 or 2 can be transferred as a MIDI system exclusive string SysEx Dump via MIDI out You can then record this string with a MIDI computer sequencer or download it using a MIDI dump program for storage on hard disk or any other storage device The sampling frequency is also transferred within the string It is also possible to receive a sample dump via MIDI input The dump is written to the memory bank selected S1 or S2 Gate low In this state LED off MIDI input is scanned As soon as an incoming sample dump is detected LED turns on and the dump data is written into the memory bank selected If a sample dump request is received via MIDI IN the sample memory is transferred via MIDI OUT as a SysEx string LED turns on as well Refer to the description of MIDI input and output in chapter 5 11 A 112 Sampler iS During Data transmission via MIDI OUT the MIDI input and gate are not scanned There fore a new dump cannot be triggered by mistake Gate high As soon as the gate goes high e g by pressing button the sample memory is transferred as
11. System A 100 or e ee Ma 1 A 112 SAM MIDI In MIDI Out Man Trig Gate In Audio IN Wave CV In CV In Audio Out PLER Modus Atten Sampler A 112 1 Introduction Module A 112 SAMPLER is a combination module including a voltage controlled 8 bit Sampler and a voltage controlled Wavetable Oscillator The module has the characteristic grungy sound of the early 8 bit Samplers and is a welcome addi tion to the A 100 s sound generating capabilities But it should not be compared with the polyphonic 16 bit MIDI samplers available on the market The module contains an A D converter ADC for recording the audio signal 8 bit resolution digital memory for storage of the the sampled signal a D A converter DAC for playback and the control unit The memory is divided into two banks S1 S2 with 64 kbyte each In wavetable mode each bank is arranged as 256 pages of 256 bytes The memory is non volatile i e after power off the sampling data in the memory is maintained A 112 Sampler Sampling mode In sampling mode the incoming audio signal is sam pled with a sampling frequency that is controlled manually and from the external control voltage input The audio signal is converted by the ADC into 8 bit digital data and sequentially written into the me mory memory address 0 65 535 With a sampling frequency of 32kHz this corresponds to 2 sec
12. manual Man Trig Button is used to trigger the sampler manually Depending upon the mode selected a Trigger or Gate leads to different actions A description of the respective functions is given in the corresponding paragraph elsewhere in this manual iS The manual trigger generated with button and the signal at the gate input are inter nally connected to produce a gate trigger signal used for all triggered gated functions System A 100 OD Function Loop not implemented Dmp Norm Dump a sample Wav Dump a wave Loop Play a loop S1 S2 Play Norm Play a sample Wav Play a wave Loop Record a loop Rec Norm Record a sample Wav Record a wave Len Input sample length required Pit Norm Pitch Shift Frz Pitch Shift with Freeze Len Input sample length required Eff Del Norm Delay Frz Delay with Freeze Len Input sample length required Rev Norm _ Reverse Delay Frz Reverse Delay with Freeze Sampler A 112 Switch Switch Switch With the 3 position switches to the operating mode is selected The table on the left lists all possible modes The modes are described in the following paragraphs In particular the gate signal gate input manual trigger controls different functions in the respective operating modes iS Please note that in some modes it is not sufficient to change the switches position to e
13. nal is sampled into the memory bank selected with switch LED is now on Recording starts at address 0 and continues until the last address 65 535 is reached and LED turns off If gate turns low before the end of the sampling memory address 65 535 is reached the record pro cess stops You can use this function to sample cho sen segments of sound e Normal play mode Audio Wave CVIn Tune CV S1 Play Norm sampling fre 2 quency In this mode a previously recorded sample in the sampling memory S1 or S2 depending upon the position of switch is played back DUEPFEA Sampler A 112 E System A 100 Gate low The module is waiting for gate high LED is off see fig 1 a Gate high When the gate level changes from low to high Play back is triggered and the audio signal in the memory bank is played back LED is now on Playback starts at address 0 and continues until the last address 65 535 is reached and LED turns off Even if the gate goes low before the end of the sampling memory is reached the playback continues see fig 1 b Only if the gate goes low and high again before the end is reached the sample is retriggered i e the playback starts again at address 0 see fig 1 c If the gate is still high when the end of the sample memory is reached the playback stops i e no loop if gate remains high For this purpose the loo
14. ntrol settings in the little white circles 24 System A 100 A 112 SAMPLER VC Sampler Wavetable Osc Gi MIDI Out Eff 2 5 x Ei O fe Play a Dmp Rec m Q m a Loop Wav e Norm C y Man 4 A In PY Rune Audio In Wave CV In ye Atten A 112 SAMPLER VC Sampler Wavetable Osc MIDI Out ay s O O jaa AR i n Rev o Loop Wav e E nom EH N y Man Gate In 7 an Audio Out 9 Run A Dmp e e Audio In Wave CV In Atten e 0 10 Ah Tune e J oe
15. occur and lead to interfe rence glitches or clicks in the audio output signal RS All functions and controls read sampling frequency length of delay memory are the same as in the delay mode see above cm Very interesting sounds can be obtained if the original audio signal is mixed with the pitch shifted signal of the A 112 using a mixer A 138a b e Freeze option System A 100 Audio Wave CVIn Tune CV Del Eff Rev Frz audio signal sampling fre Pit quency The effect modes delay reverse delay and pitch shift may also run with the Freeze option In this case the audio input is no longer sampled and the memory data no longer overwritten Instead the frozen memory data are played back The parameters memory length Len and sampling frequency deter mine the effect Gate control The module is waiting for gate high LED is off The initial sampling frequency is determined If only a short gate pulse appears i e gate turns to high only for a short time and becomes low again the effect selected functions without freeze LED is off As soon as gate turns high and remains high the freeze option of the effect in question is active LED is on The data in the memory are frozen as long as the gate remains high Sampler A 112 When gate turns low the freeze option is cancelled and the module returns to the respective effect without freeze To re activate
16. ode with modulated wavetable page number Waves recorded in this way may be played back in the normal play mode often leading to some fairly drastic effects In this mode A 112 works as a wavetable oscillator The wavetable number page that determines the sound of the audio output is set by the control voltage applied to the audio wave CV input Gate low The module is waiting for gate high LED is off The initial sampling frequency i e the first frequency when gate turns to high see below is set Pre listening mode is also used to find out and set the sampling frequency Gate high When the gate goes high the wavetable number audio wave input and the sampling frequency tune control and CV input are set and playback of the recorded wavetable begins using the sampling fre quency previously set LED turns on When the end of the wavetable is reached the process starts again DHEP FER i e the next wavetable and the next sampling fre quency are determined This continues until the gate goes low When a dynamic voltage 2 5 2 5V is used as the wavetable control voltage e g ADSR output connec ted to audio wave input wavetable are swept memory bank Audio In 0 40 O30 t ENEZE 0 20 MK 040 55 etna aiw zez ee O EPS Nn NG ae a 0 00 DAD e E E e E E e a
17. onds sampling time During playback the sampling data in the memory is read sequentially address O 65535 and converted into the corresponding audio signal by the DAC The sampling frequency in play mode is controlled manu ally and from the external control voltage input Play back is stopped if the last memory address 65535 is reached Via MIDI dump the sampling memory can be sent to a computer for storing the data on hard disk or any other storage device The computer may also transmit sampling data to the A 112 via MIDI dump Wavetable mode In wavetable mode the memory access is not sequen tially but by page The page number is selected by an external voltage This voltage can be may genera ted manually e g with the manual control voltage System A 100 QHEP FER source A 176 or it may come from any other voltage source e g LFO ADSR Sequencer Both record and play take place in a loop whereby the complete page is always passed through When reaching the end of a page the run control determines if a jump to another page takes place or the loop remains in the same page depending upon the voltage controlling the wa vetable page Playback with a dynamic control voltage e g ADSR LFO Random Sequencer MIDI to CV results in sweeping through the different pages Wavetable principle If the memory of the A 112 contains sui table wavetables in the 256 pages the result is a voltage controlled Wavetable
18. ontrol setting 10 The reverse delay effect seems to go very strange with tune control settings of about 1 5 down to 0 i e the reverse delay becomes a normal delay but with ex treme distortion System A 100 4 In Outputs Audio In Wave CV In At this socket the audio input signal is patched in i e the signal to be sampled or used for effects This is a line level input 2 5V or 5Vss Note that the audio signal must be at line level microphones won t give enough output iS Exception In wavetable play mode this is the wavetable control voltage input 2 5 2 5V not an audio signal input e CV In Control voltage input for sampling frequency du ring record or pitch tune during play This input follows to the 1V oct standard and has 1 4 semitone resolution iS The control voltage applied to CV in is internally added to the voltage generated by the tune control Gate In At the Gate input the gate signal is patched in The function depends upon the mode selected DHEP FER System IS The gate signal applied to this socket is inter nally connected with the signal coming from the button If either of these is high the module gate is high Gate In Man Trig result Gate high high high high low high low high high low low low Audio Out Socket is the audio output of the A 112 iS The audio signal from the DAC passes a simple low pass filter to suppress the sam
19. ory are used for each step displayed by different sound symbols Regar ding offset attenuation and LFO frequency see the notes on the previous page The sequencer control voltage Post Out 1 is used to control the decay of an VC ADSR i e for different decay times for each step Instead of an LFO an ADSR or VC ADSR may be used The attack control is used in this case to adjust the speed of sweep decay sustain and release con trol 0 19 A 112 Sampler Wavetable playback of a normal sample Very interesting sounds can be obtained if a normal sample is played back in wavetable mode especially if human voice is recorded During normal sample playback the sample length depends upon pitch and the so called Mickey Mouse effect occurs If the wavetable mode is used the sample length depends only upon the slope of the controlling voltage e g sawtooth but not upon the pitch This is adjusted independently with the tune control and pitch CV 20 System A 100 Suggestions for sound experiments e lf the slope of the voltage controlling the wavetable is running backwards e g a falling sawtooth sam pled words seem to be spoken backwards sort of e By selective scanning of a spoken sample one may obtain voice or vowel loops e Using a random or S amp H voltage for controlling the wavetables leads to the basics of what is often referred to as granular synthesis For the above suggestions it is important that
20. p mode is used Audio Out Sample Gate CD fig 1 normal play mode e Loop record mode Audio Wave CVln Tune CV S1 Rec Loop audio signal sampling fre S2 quency only if Gate low This mode is very similar to the normal record mode see above The only difference to the normal re cord mode is that record continues when the end of the sample memory is reached and the gate level is still high A 112 Sampler In this case the record starts again at the first memory address This loop continues LED on until gate turns low e Loop play mode System A 100 Audio Wave CVln Tune CV S1 Play Loop sampling fre S2 quency In normal play mode the playback stops if the end of the sample memory is reached The loop play mode allows the continuous playback of a pre defined section of the sample memory Gate function As long as the gate level is high the sample is played continuously When the end of the sample is reached playback starts again at the beginning see fig 2 a LED is on As soon as the gate goes low the present position within the sample is defined as loop end see fig 2 b Playback starts at the beginning address 0 and runs continuously from the beginning to the loop end as long as the gate level remains low see fig 2 loop 1 If ga
21. pling frequency It is possible to bypass this internal filter if a more sophisticated low pass filter A 120 A 121 A 122 is used or if the sampling frequency should not be sup pressed for special effects For this the inter nal jumper J1 has to be removed A 100 Sampler A 112 MIDI In Socket is the MIDI input used to receive sample data SysEx dump via MIDI For this the dump or wave dump mode has to be selected see above and the gate has to be low Moreover a sample dump request or a wave dump request message can be received by the A 112 in this mode The MIDI SysEx message for a sample dump re quest has the following structure FO 00 20 20 Doepfer SysEx ID 7F lt bank gt bank number 00 S1 01 S2 F7 When receiving this message the A 112 transmits at the MIDI output a sample dump LED is on The length of the dump is 74 909 bytes altogether Additio nally the current sampling frequency is transmitted The SysEx message for a wave dump request has the following structure 17 A 112 Sampler FO 00 20 20 Doepfer SysEx ID 7D lt Wave Nr Bit 7 1 gt lt Wave Nr Bit 0 gt F7 As the data range in a SysEx message is 0 127 7 bit the wave number requires 2 bytes Example Dump of wave no 201 11001001 64 110100 01 mq When it receives this message the A 112 transmits a wave dump at the MIDI output LED is on The length of the dump is 305 Bytes altogether
22. te turns high see fig 1 c the loop end is cancelled and the sample playback uses the full range again i e loop end end of sample memory see fig 2 d If the gate goes low again a new loop end is set see fig 2 e loop 2 To exit loop play mode a short trigger pulse max duration 100 ms is required see fig 2 f Audio Out Sample z M Gate lb c e la a gt Ls Lg Ty f Loop 1 Loop 2 fig 2 Loop play mode e Wave record mode Audio Wave CVIn Tune CV S1 Rec Wav audio signal sampling fre S2 quency if gate low wavetable number if gate high In this mode one or more wavetables are recorded into the memory bank selected The number of the wavetable page results from the position of the Tune control and the voltage applied to the CV input 6 Gate low The pre listening mode is active LED is off the audio signal at input is digitized by the ADC re converted by the DAC and forwarded to audio output for pre listening All functions and controls overload clipping adjust ment of sampling frequency are the same as in the normal record mode see above System A 100 Sampler A 112 Gate high When the gate goes high record starts LED is on The last sampling frequency while gate was low is used as the sampling frequency The wavetable num ber page is derived from
23. the period of the sampled sound fits almost exactly into the space allotted to each wavetable 256 Bytes If the result is not satisfactory another record sampling fre quency should be used until the desired sound is obtained 7 Clock 1 3 4 5 6 7 8 m m u FH Trig 1 m m m s9 m E E Gte k k k k lt k k k Pos Out 1 S8 HCtrl 1 V k k k k W k k Pos Out 2 S8 HCtrl 2 System A 100 Sampler A 112 Clock fig 6 sequencer controlled wavetable playback 21 A 112 Sampler 6 A 112 Sample Dump Loader The A 112 MIDI interface enables the transfer of sam ple and wave data from and to the device using MIDI SysEx strings For that purpose a standard MIDI se quencer may be used In addition we include a 3 1 2 floppy disk containing a A 112 sample dump loader software for PC Version 1 2 of this software see fig 7 enables bi directional transfer between A 112 and the PC Sam ples and waves can be organized and stored on the storage device e g hard disk of a PC In the PC each sample or wave can be assigned any name DOS convention i e max 8 characters and stored as a WAV file 8 bit mono The A 112 format is automati cally converted into the WAV format Conversely any WAV file can be transferred to the A 112 The program reads any WAV file in 8 12 or 16 bit mono or stereo
24. xit the mode In the following description of the modes you will find detailed information on how to exit a selected mode A 112 Sampler e Normal record mode System A 100 Audio Wave CVln Tune CV S1 Rec Norm Audio signal sampling fre S2 quency while Gate low In this mode an audio signal at audio input is recorded into one of the 2 memory banks S1 or S2 depending upon the position of switch Gate low In this case the pre listening mode is active LED is off the audio signal at input is digitized by the ADC re converted by the DAC and forwarded to audio output for pre listening The pre listening mode contains an overload clip ping function as soon as the audio signal exceeds a predefined upper or lower threshold the LED lights up for a short moment about 10 ms During this time the audio signal is not scanned and the output remains at the last DAC value The onset of clipping i e overload distortion is immediately audible iS The sound quality in the pre listening mode is very poor The quality if a signal is recor ded and played back is much better QHEP PER The pre listening mode is also used to find out and set the sampling frequency When record mode is entered see below the last sampling frequency in pre listening mode is used Gate high When the gate level changes from low to high Record is triggered and the audio sig
25. y mode but writing into the delay memory is performed forward and reading the delay memory is performed backward As this is a very simple bog standard algorithm overlap ping effects may occur and lead to interference glit ches or clicks in the audio output signal 13 A 112 Sampler iS All functions and controls sampling fre quency length of delay memory are the same as in the normal delay mode See above e Pitch shift mode System A 100 Audio Wave CVIn Tune CV Eff Pit Norm audio signal sampling fre quency In pitch shift mode the audio input signal is sampled and played back at the audio output with shifted pitch tuning iS Memory bank S2 is overwritten in this mode Principle The incoming audio signal is sampled with a fixed sampling frequency about 16 kHz and written into memory bank S2 Each sample increases the memory position by 1 Simultaneously the memory is read out with a sampling frequency that is determined by the Tune control and the voltage applied to the CV input e If the read frequency is nearly the same as the write frequency i e about 16 kHz no pitch shift occurs just a delay depending upon the memory length Len 14 QHEP FER If read and write frequency differ the audio signal is read out faster or slower and the pitch shift effect occurs Because of this very simple bog standard algorithm overlapping effects may

A-112

Contents

Download Pdf Manuals

Related Search

Related Contents