- pro audito winterthur
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1. where the Cochlear cochlear implants are produced and talk to the engineers They are considering to integrate the telecoil even in the tiny ESPrit 22 Ear Level Speech Processor for Nucleus 22 recipients Up to now the telecoil is an accessory for cochlear implants 12 At the ICED2000 congress I talked to Mr Douglas Clutton from MED EL In the meantime August 16 2000 I got an email from Mr Stefan Sroka from MED EL telling me the following I want to inform you that we are currently working on an assistive listening device ALD for our TEMPO behind the ear speech processor This device will contain an active telecoil to enable the users of the TEMPO to couple to loop systems This ALD will comply to IEC 60118 1 and can be connected to the external audio input of the speech processor Our ALD will come up during this year Beverly Biderman Wired for Sound A Journey into Hearing Toronto Trifolium Books 1998 p 11 The range between the softest and loudest sounds I can hear with my implant is less than one fifth of the range of a normal hearing person and therefore my ability to make fine distinctions between signal and noise or foreground and background is poor This is why background noise is so difficult for most people who wear a cochlear implant Paula Hendricks amp Norman Lederman Looping the World Re discovering a simple and effective hearing assistance system Part I Induction loop basics history and adv2. Informationsschriften des Schwerh rigen Vereins Winterthur Siemens Signia Behind the Ear Instruments Operating Instructions The middle position T is intended for telephoning and for using inductive loops e g in churches theatres or lecture rooms Using the T position for telephoning requires that the telephone is suitable for hearing instruments and emits a corresponding magnetic field Unfortunately not all modern telephones especially cordless telephones and mobile phones produce a magnetic field Siegfried Karg Die unsichtbare Behinderung sichtbar gemacht in dezibel Zeitschrift f r H ren und Erleben 3 97 pp 4 7 Siegfried Karg See how well I can hear in IFHOH Journal Volume 20 1 February 1999 pp 10 13 Jan Gronborg Eriksen A Ramp is not enough Accessibility of Houses of Worship SHHH panel Boston 14 6 98 www churchear org
3. are used much more often in European countries Matthew H Bakke Harry Levitt Mark Ross Faye Erickson Large Area Assistive Listening Systems Review and Recommendations Final Report to United States Architectural and Transportation Barriers Compliance Board U S Access Board Lexington School for the Deaf Center for the Deaf Jackson Heights NY December 1999 p 3 quoted from www hearingresearch org 8 International Electrotechnical Commission IEC Standard 118 4 Methods of measurement of electro acoustical characteristics of hearing aids Part 4 Magnetic field strength in audio frequency induction loops for hearing aid purposes Geneva 1981 Ingenieur Alfred Sturma Vienna Austria informed me that the standard was reworked by the International Electrotechnical Commission in 1998 The new standard is EN 601 18 4 The hearing aid manufacturer Siemens explicitely mentions the strength of the telecoil for their different models Siemens Handbuch HdO Ger te H rspulenempfindlichkeit bei 1 6 kHz re 20 Pa 1 mA m m As far as I know until now only two manufacturers of cochlear implants COCHLEAR and ADVANCED BIONICS produce speech processors with a telecoil up to now I urgently advise the other manufacturers to do the same because reverberation background noise and long distances to the sound source are even greater problems with the CI than with the hearing aid 3 Personal experience 30 y
4. high frequencies Therefore the quality of the sound and the speech intelligibility is much better In new buildings and in renovated buildings only induction loop drivers based on current should be used e g Ampetronic United Kingdom Univox by Bo Edin AB Sweden Logia Oticon Lydsystemer AS Denmark 7 Low spillover systems Normal induction loop systems produce a certain spillover of the magnetic field This could be awkward in adjacent rooms e g classrooms cinemas Up to now this problem prevented installation in such rooms This problem has now been addressed a 3 D Loop System of Oval Window Audio USA The US manufacturer of AFILS Oval Window Audio in Nederland Colorado has developed a so called 3 D loop system with little or no spillover b Phase Array System of Ampetronic Ltd United Kingdom The English firm Ampetronic has now developed a system which limits the spillover of the magnetic field very much so that it is now possible to have AFILS even in rooms next to each other You need a certain loop design which Ampetronic simulates for you on their computer according to the measurements of your room A special phase shifter is also needed Often there is an additional need for metal loss correction 8 The situation in Europe and in the USA Let me mention just some examples Ata wedding in the old monastery church Paradise in Langwiesen Switzerland on June 10 2000 where I had
5. of lack of space Well designed Porsche design Behind The Ear hearing aids with strong telecoils are the future b Hard of Hearing People and Hard of Hearing Organizations should put pressure on hearing aid and CI manufacturers to encourage them to only produce hearing aids and CIs with telecoils c In countries where hearing aids are financed by an organization impairment insurance of the state e g Switzerland for men below the age of 65 and women below the age of 63 the organization should subsidize only hearing aids or CIs in which a telecoil is included If someone wants a hearing aid without a telecoil he or she can get it on the free market but then should pay the full price himself or herself In Sweden only hearing aids with telecoils are subsidized by the state I think this leads into the right direction d In a room with more than 50 seats always ask for an AFILS Handicapped persons in wheel chairs get their ramps and lifts even if only one handicapped person has to use it e Don t forget to keep your head upright in a venue with an AFILS If you fall asleep the telecoil is no longer in an upright position and you will not get the advantage of it anymore D schwerh LOOP007 31 10 2000 Karg a Siegfried Karg Wie hast du s mit der IndukTion Die Gretchenfrage bei der Anschaffung eines H rger ts Orientierungshilfe f r Konsumenten Winterthur Schwerh rigen Verein 1998 16 pages WINFO H RMATIV Nr 1
6. telecoil is quite large in comparison to the rest of the electronic components in the aid smaller telecoils are included to reduce the overall size of the hearing aid The amplification is then weaker in the T position than in the M position 1 In many In the Ear hearing aids and especially in Completely in the Canal CIC hearing aids there is no room for the telecoil Because a lot of hard of hearing people consider hearing impairment as a stigma they want almost invisible hearing aids Weise Herr K Franz Wimmer und Frau Veronika Jank zur Verfiigung Dabei zeigte sich dass indukTive H ranlagen auch f r den CI Tr ger unter Verwendung des Audioselectors Vorteile im Hinblick auf Sprachverst ndlichkeit und Nebenger uschfreiheit bringen Frau Jank war es m glich problemlos Sendungen im Fernsehen zu verfolgen Herr Wimmer konnte sich u a in der Auferstehungskirche in Wien von der einwandfreien Funktion einer indukTiven H ranlage berzeugen Aussage des Herm Wimmer Ich habe noch nie so gut verstanden wie mit dieser Anlage The Swiss hearing aid company PHONAK mentions on its website that with a hearing aid you have problems with reverberation already at a distance greater than 2 meters and therefore suggests their wireless FM system MicroLink as a possible solution to the problem This is especially true for the USA IL systems are the oldest and least employed of the existing ALS in this country they
7. Betrieben in der Stadt Graz Graz 1999 32 Oskar Ulrich Hallo Wo seid Ihr H rbehinderten in dezibel Zeitschrift f r H ren und Erleben 11 96 p 2 Schweizerische Bundesbahnen Informationen fiir behinderte Reisende 3 Siegfried Karg Nichts verstanden Tipps f r H rger tetr ger in Kirchen und Vortragss len mit induktiven H ranlagen Ringleitungen 1998 meet IEC standard 118 4 60118 4 and are driven by voltage amplifiers instead of specific induction loop drivers using current There has been an upsurge in the last years and there are many positive examples such as a tour bus in Winterthur or the United Bank of Switzerland UBS in Winterthur where two desks have been equipped with induction loop systems g Germany Not many AFILS exist and those are mostly not conforming to EN 60118 4 The German Hard of Hearing Union Deutscher Schwerh rigenbund has published a brochure claiming that AFILS were old fashioned h USA There is a small renaissance of AFILS The main problem is that according to Mark Ross only thirty percent of the hearing aids in the USA are equipped with a telecoil Self Help for Hard of Hearing People supports telecoils in a position statement SHHH recommends that all hearing aid dispensers inform their patients of the function and potential advantages of T coils during the course of the hearing aid selection process and further strongly suggests their inclusion in the hearing
8. Rev Siegfried Karg B D Th M President Hard of Hearing Association of Winterthur Bolrebenweg 15 CH 8406 Winterthur Switzerland Tel FAX 41 52 202 09 40 Email siegfried karg bluewin ch To Loop or not to Loop Advanced Technology Induction Loop Systems for Hearing Aids and Cochlear Implants Paper presented at the 6 International Congress of Hard of Hearing People in Sydney Australia July 4 2000 and at the 19 International Congress on Education of the Deaf and 7 Asia Pacific Congress on Deafness in Sydney Australia July 13 2000 revised version 1 Introduction Reverberation background noise and long distance to the sound source are the three main enemies of speech intelligibility for people with hearing aids and cochlear implants To fight these enemies there are three weapons 1 Induction Loop 2 Infrared 3 Frequency Modulation FM I am convinced that the Audio Frequency Induction Loop System AFILS is the most adequate the psychologically least problematic and the most cost effective technology Therefore I will concentrate in my paper purely on AFILS There are certain situations in which you have to use infrared or FM but the AFILS confirming to state of the art technology is according to my view the basic technology for assistive listening devices 2 The need for assistive listening devices a A Hearing Aid is not enough A hearing aid or a cochlear implant is a great help to people who are
9. aids SHHH and the Johns Hopkins Center for Hearing and Balance have also produced a video film on the same subject The Telecoil Plugging into Sound 9 Technical Recommendations a Use only single loop cable b The diameter of the loop cable 0 5 mm 0 75 mm 1 mm 1 5 mm 2 5 mm has to be calculated according to the dimensions of the room c A special induction loop driver using current and not voltage has to be used for the loop You may pick up the signal from a separate microphone or from one which is already being used for the public address system d After correct installation of the loop the system has to be adjusted properly through a qualified person measuring the field strength and also the frequency response Once the system is correctly adjusted there is normally no need for readjustment e The person responsible for the room should be instructed properly A written user s manual should be handed out in which the location of the loop cable its diameter and the measuring sheet should be included f The international IFHOH icon accepted in 1985 should be placed at the entrance of the room so that it is clearly visible to everybody that an AFILS is installed 4 Walter Buchs Gregor Schafer H ranlagen in Kirchen und ffentlichen S len Leitfaden f r Besteller und Bedienungspersonal W nnewil H rbehindertenverein Deutschfreiburg 1998 Induktives H ren mit dem H rger t Eine Gebrauchsanleit
10. ancements www ovalwindowaudio com The first portable hearing aid to incorporate a telecoil was the Multitone Model VPM in 1938 following an early patent for an IL hearing assistance system by Joseph Poliakoff of Great Brtain in 1937 Interestingly IL systems were used in Europe long before becoming available in the USA making its first appearance as an imported product after World War II S David A Preves A Look at the Telecoil Its Development and Potential in SHHH Journal September October 1994 p 7 In 1947 Samuel Lybarger then chief engineer at the Radioear hearing aid company discovered that when people used telephones magnetic energy leaked out from the receiver in the telephone handset Even more significantly he also found that this magnetic leakage could be useful to people with hearing loss if it was picked up with a small coil in the hearing aid Lybarger 1947 In the USA you have the Americans with Disabilities Act ADA since 1990 The Accessibility and Transportation Board has issued Accessibility Guidelines for Buildings and Facilities amended through January 1998 Under the section Accessible Buildings New construction you find at point 19 Assembly areas b This paragraph applies to assembly areas where audible communications are integral to the use of the space e g concert suitable for countries where money is scarce because this is the cheapest technology of assistive listening devi
11. ces 5 Design of systems where spillover is no problem 1 Priority The loop is placed alongside the walls of the room at floor level or up to 40 cm below floor level 2 Priority If it is not possible to place the loop at floor level the loop can also be placed along the edges of the ceiling if the room is not too high For a ceiling loop however much more amplification is needed than for the floor loop The wire of the loop should be placed in a standard plastic pipe used for standard electrical installations If the plastic pipe is put in a new building before the building is finished the costs are almost nil Therefore AFILS should be planned early The plastic pipe should contain only the loop wire and no other electrical wires because every wire in which electricity flows produces a magnetic field This field will be picked up and amplified by the induction loop system producing a disturbing hum Other electrical wires should not be put parallel to the loop or within a distance of at least 20 cm Electrical wires crossing the loop wire do not cause any harm No high voltage wires should cross the loop area because this produces additional disturbing hum Already in the planning process the person planning the high voltage system should be in close contact with those responsible for the AFILS and the normal electrical wiring If they communicate well a lot of irrevocable mistakes could be avoided In larger assembly areas with fixed seat
12. e listening system shall be provided The minimum number of receivers to be provided shall be equal to 4 percent of the total number of seats but in no case less than two Signage complying with applicable provisions of 4 30 shall be installed to notify patrons of the availability of a listening system 4 33 7 Types of Listening Systems Assistive listening systems ALS are intended to augment standard public address and audio systems by providing signals which can be received directly by persons with special receivers or their own hearing aids and which eliminate or filter background noise The type of assistive listening system appropriate for a particular application depends on the characteristics of the setting the nature of the program and the intended audience Magnetic induction loops infra red and radio frequency systems are types of listening systems which are appropriate for various applications Beverly Biderman Wired for Sound A Journey into Hearing Toronto Trifolium Books 1998 p 12 Treble sounds give 95 of the information used in understanding speech Bass sounds while they account for 95 of the volume of speech provide only 5 of the information used for comprehension Siegfried Karg Wider den Widerhall Raumakustik und indukTive H ranlage in dezibel Zeitschrift f r H ren und Erleben 12 98 p 9 Advanced technology induction loop drivers using current instead of voltage perform well even in the
13. ears ago I met a hard of hearing person for the first time At that time my fianc e was staying with her aunt who has been hard of hearing since childhood This aunt could never understand me on the telephone I tried to speak louder but that only made things even worse Someone told me that you could get a special phone with inductive coupling With this phone you could use the telecoil of the hearing aid Finally the aunt got such a phone and since that time she can understand me perfectly on the phone For me this experience was the key for my activism in favour of audio frequency induction loop systems 4 History AFILS is a technology which has been known since the thirties or forties The system became less popular when infrared systems and FM systems appeared These systems however require a special receiver For the induction loop system on the other hand you only have to switch your hearing aid from microphone M to telecoil T allowing you to use the individual amplification of your personal hearing aid There is a renaissance of AFILS in Europe and also in the USA Hard of hearing people and cochlear implant users realize the many advantages of this system In my view it is especially 10 I sent a questionnaire in May 2000 to the following manufacturers Cochlear Advanced Bionics MED EL Cochlear and Advanced Bionics responded At the ICED2000 congress I had the privilege to visit Cochlear Limited in Lane Cove Sydney
14. erh rigenbund DSB Ratgeber 4 Technische Hilfen f r H rgesch digte Berlin DSB 1996 Induktionsanlagen Sie entsprechen nicht mehr dem heutigen Standard sind sehr st ranf llig k nnen auch in der Lautst rke nicht individuell reguliert werden sind jedoch in vielen Versammlungsr umen und Kirchen installiert und kommen aus Kostengr nden immer noch h ufig zum Einsatz Self Help for Hard of Hearing People Inc Position Statement on Telecoils in Hearing Loss September October 1996 pp 29 30 10 minute video available from Self Help for Hard of Hearing People Inc Bethesda MD USA g If it is not possible to install the loop in the whole room a drawing should show which part of the room is looped h A sign should remind people where the loop wire is installed e g under the carpet so that it will not be harmed if e g a hole has to be driven in the floor for another installation purpose 10 Recommendations for Hard of Hearing People and CI people a Accept only hearing aids or cochlear implants with a strong telecoil from your dispenser This has nothing to do with costs The telecoil is extremely cheap compared to the hearing aid or CI about 2 of the cost of a hearing aid This eliminates Completely in the Canal CIC hearing aids although Bill Clinton wears them because there is not enough space to include a telecoil If you have a small ear canal this even eliminates In the Ear IO hearing aids because
15. hearing impaired but it is not enough While communication between two persons facing each other works very well it will become impossible in a place with strong reverberation background noise or long distances to the sound source e g a person speaking or a loudspeaker b Technology does not yet replace our brain With intact ears our brain can select which sound source you want to hear When two persons talk to each other in a room where the radio is on and a clock is ticking at the same time our brain can partly filter out the music or the sound of the clock Even the most advanced digital hearing aid can do this only partially or not at all c We need hearing aids cochlear implants Plus In difficult hearing situations e g house of worship auditorium there is a strong need for additional assistive listening devices in conjunction with the hearing aid or cochlear implant The paper has been included in the Congress CD ROM Proceedings Email ICED2000 tourhosts com au Kurt Eggenschwiler Karl Baschnagel Aktuelle Aspekte der Kirchenakustik in Schweizer Ingenieur und Architekt volume 117 Nr 25 25 June 1999 pp 560 564 Carsten Ruhe Grunds tzliche berlegungen zu Beschallungsanlagen in Kirchen und grossen Veranstaltungsr umen Typoskipt no year 23 pages Carsten Ruhe G nstige Raumakustik hilft H rgesch digten in Beratende Ingenieure 11 12 1998 pp 132 137 Siegfried Karg Wider den Widerhall Raumakustik
16. hem do not Oticon Lydsystemer A S Teleslynge og h jttaleranl g 5 Cirkulzere om tr dl se horeanlaeg i kirkerne 21 marts 1986 www churchear org Kirkekonsulenten informerer 1 1993 Teleslyngeanlegg i KIRKEBYGG Krav til teleslyngeanlegg In 1998 the church council published the following brochure Gj r deren hey gj r porten vid Om tilrettelegging for funksjonshemmede i menighetene Oslo 1998 7 Nordiska N mnden f r Handikappfr gor Nordic Committee on Disability Requirement specification for hearing aids 4 edition 1994 10 26 3 3 5 Induction pick up coil The hearing aid shall have an induction pick up coil In a vertical magnetic field as described in the IEC 118 1 the sensitivity of the pick up coil shall not increase more than 2 dB when the hearing aid is tilted in any direction from the position as worn on a head and torso simulator IEC 959 Provisional head and torso simulator for acoustic measurement on air conduction hearing aids tilted 10 forward Note In some cases eg owing to small size a hearing aid without an induction pick up coil may be accepted 4 7 Induction pick up coil An inductive input signal of 31 6 mA m shall give the same output signal level as an acoustical input signal using the M position of 57 67 dB SPL in the frequency range 1000 4000 Hz and of 55 67 dB SPL in the range 500 up to 1000 Hz This requirement applies for both T and MT positions and for any se
17. installed a mobile induction loop using the Ampetronic ILD 252 induction loop driver Kurt Wirth Z rich who wears a Cochlear cochlear implant with a telecoil as accessory was very much impressed about the speech intelligibility on the induction loop Norman Lederman Selecting a Loop System www ovalwindowaudio com All conventional loop systems exhibit signal spill over or bleeding outside the loop wire This means that adjacent rooms in the vertical as well as horizontal plane cannot have loop systems operating at the same time without interfering with each other Paula Hendricks and Norman Lederman Development of a three dimensional induction assistive listening system in Hearing Instruments vol 42 No 9 1991 Norman Lederman and Paula Hendricks Induction Loop Assistive Listening Systems in Communication Access for Persons with Hearing Loss Compliance with the Americans with Disabilities Act ed by Mark Ross Baltimore Toronto Sydney York Press 1994 pp 19 39 Ampetronic Information Sheet Induction Loops Their Purpose amp Functions p 4 Audio Frequency Induction Loops create a magnetic field which is not constrained to the area of the loop installation Normal systems using a perimeter loop create spillover so that they are clearly audible some 3 to 4 loop sizes away There are many instances where this is unacceptable such as in multiscreen cinema complexes conference room situations council chambe
18. quires special receivers for each hearing impaired person Therefore installers are not very much interested in the AFILS g The AFILS is an invisible technique for an invisible impairment Once installed nobody can see anything of the system If a public address system does not function people realize it immediately because no sound comes out of the loudspeakers If the AFILS malfunctions only the user is affected h Icons which signalize the installation of this invisible technique are missing in most looped venues In 1985 the International Federation of Hard of Hearing People IFHOH adopted an icon as the official symbol for AFILS It should be used worldwide because this would allow immediate recognition i Most AFILS are installed incorrectly not fulfilling the standard IEC118 4 which was set by the International Electrotechnical Commission in 1981 Hard of Hearing organizations should insist that this norm should be adhered to The customer should make a written contract with the installer that the AFILS conforms to IEC 118 4 since 1998 IEC 60118 4 If not the installer should be fined This would eliminate firms which have very little knowledge of AFILS j A lot of hard of hearing people know little to nothing about the function of the telecoil in the hearing aid Even in looped areas they therefore fail to use the AFILS k Hearing aid manufacturers have included telecoils of different strengths in their hearing aids Since the
19. rs multiple common rooms in sheltered house etc AMPETRONIC have developed various technologies to minimise the loop spillover such that the above mentioned situations can be easily resolved Typically in multi screen cinemas we can provide a large portion of the seating in each auditorium with full quality sound while keeping the crosstalk from adjacent cinemas more than 40 db below the normal signal for all the seats in the auditorium ensuring compliance with film classification regulations This is also applicable to conference rooms Additional techniques can be used to create secure systems where absolute secrecy is vital www ampetronic com 3 Ampetronic Information Sheet Induction Loops Their Purpose amp Functions p 18 A serious problem in modern buildings is the presence of large amounts of metal in the floor and or ceiling of the buildings This metal causes a frequency dependent loss of magnetic field The actual loss can be up to 3db per octave with a lower corner frequency between 0 1 Hz and 100 Hz This loss equals 15dB change from 150Hz to 5kHz There is no simple solution but the MLC 9 Metal Loss Corrector permits the frequency response to be levelled being fully adjustable from 0 to 3db per octave a Denmark Practically all churches are equipped with an excellent AFILS The governing body responsible for churches issued recommendations for AFILS as early as March 1986 The loop system will be checked eve
20. ry year to see if it still meets the standards b Norway In the year 1993 the church council issued a publication on AFILS which was sent to all churches c Sweden In Sweden the Nordic Committee on Disability has issued Requirement specification for hearing aids The telecoil is an integral part of it d Great Britain There a special Code of Practice for AFILS exists Loop systems in public buildings must be installed to British Standard Code of Practice for Audio Frequency Induction Loop Systems BS 7594 If you quote this code of practice in all specifications and contracts it should help to ensure that your induction loop system is designed and installed to professional standards works properly is safe and meets regulations e Austria There are not many AFILS that meet the standard According to an official regulation effective in 1991 every audiologist should have an induction loop system to check the inductive coupling of the hearing aid According to the president of the Austrian Union for Hard of Hearing People OSB Hans Neuhold very few have such a system Since 1997 there has been a fantastic renaissance of AFILS in Austria starting with the installation of a new AFILS in the Church of the Resurrection in Vienna f Switzerland All public telephone booths have inductive couplers Most train stations have at least one ticket corner with AFILS In most churches there are AFILS Many of t
21. s e g houses of worship where there is an aisle in the middle ofthe room a loop design like a figure 8 could be planned If this is done the direction of the current must go in the same direction in the aisle area because opposite directions will kill the magnetic field After installation the loop driver has to be adjusted correctly conforming to standard IEC 118 4 IEC 60118 4 Magnetic field strength and also frequency response should be measured 6 Voltage versus current In former times the same amplifier that was used for the public address system was used as a driver for the induction loop This actually works But AFILS based on voltage perform poorly in the high frequencies which are so important for speech intelligibility The impedance of the loop wire increases with the high frequencies Therefore the amplifier has to furnish more current The audio amplifier based on voltage cannot produce a current which is independent of the frequency and lecture halls playhouses and movie theaters meeting rooms etc Such assembly areas if 1 they accommodate at least 50 persons or if they have audio amplification systems and 2 they have fixed seating shall have a permanently installed assistive listening system complying with 4 33 For other assembly areas a permanently installed assistive listening system or an adequate number of electrical outlets or other supplementary wiring necessary to support a portable assistiv
22. tting of the tone controls of the hearing aid When switching between control positions T and MT the sensitivity of the induction pick up coil shall not change more than 2 dB in the frequency range 500 to 4000 Hz 8 British Standard Code of Practice for Audio Frequency Induction Loop Systems AFILS BS 7594 1993 RNID Factsheet Induction loops and infrared in public buildings www rnid org uk 30 676 Verordnung des Bundesministers f r wirtschaftliche Angelegenheiten mit der die Verordnung ber Aus bungsvorschriften f r das gebundene Gewerbe der H rger teakustiker ge ndert wird Er muss mindestens ausgestattet sein mit g einer elektrischen Ringleitung oder einer gleichwertigen technischen Einrichtung zur berpr fung der induktiven bertragungseinrichtungen Siegfried Karg Fachgutachten zu Handen des Oberkirchenrats betreffend kombiniertes Lautsprecher und Schwerh rigensystem in der Auferstehungskirche Wien Lindengasse 44a 1997 8 Seiten Alfred Sturma Induktive H ranlagen Aufbau und Funktion Ein kurzer Leitfaden f r Anwender und H rger tebenutzer Wien 1997 Since 1999 there is a Checkliste f r IndukTive H ranlagen Ein Ratgeber f r Unternehmen und Institutionen herausgegeben von der Arbeitsgemeinschaft sterreichischer Schwerh rigenvereine Hans Neuhold Unerh rt Erhebung h rbehindertengerechter Ausstattungen in ffentlichen kulturellen sozialen und allgemein zug nglichen Einrichtungen und
23. und indukTive H ranlage in dezibel Zeitschrift f r H ren und Erleben 12 98 pp 8 10 Siegfried Karg Aktuelle Aspekte der Kirchenakustik in dezibel Zeitschrift f r H ren und Erleben 10 99 pp 7 8 Siegfried Karg Gut h ren ohne Pfeifen mit induktiven Schleifen Die Position T am H rger t in dezibel Zeitschrift f r H ren und Erleben 7 8 96 pp 24 27 Siegfried Karg Kultur und Kongresszentrum Luzern keine Heldentat f r H rbehinderte in dezibel Zeitschrift f r H ren und Erleben 7 8 2000 pp 41 42 Mark Ross When a Hearing Aid is Not Enough Consider other Types of Hearing Assistance Technologies www audiology org ross Alfred Sturma Induktive H ranlagen und das CI www acs akustik at IndukTive H ranlagen konnten bisher nur mit Ger ten des australischen Herstellers COCHLEAR getestet werden Als Tester stellten sich in dankenswerter d The aim of the assistive listening system is to minimize the distance to the sound source and to cut out reverberation and background noise e Although the AFILS is the oldest technique it has been widely neglected until recently A renaissance of this system worldwide is vital and I am fighting for it f In my view the AFILS has been neglected due to the following reasons The AFILS is the cheapest system and is therefore not very profitable for the installer You can earn much more money by installing an expensive FM system or an infrared system which re
24. ung f r H rger tetr gerinnen und H rger tetr ger Mit einem Verzeichnis der H ranlagen in ffentlichen Geb uden im Kanton Bern und in Deutsch Freiburg Bern pro audito Schwerh rigen Verein Region Bern no year 35 Siegfried Karg Reisecar mit induktiver H ranlage in dezibel Zeitschrift f r H ren und Erleben 3 96 pp 20 21 3 Ruth M ller Machen Sie mit Audio Watching 2 in DSB Report 1 98 37 Merkblatt zum Einbau von H ranlagen f r Schwerh rige in Kirchen und Versammlungsr umen hrsg von der AFESS Arbeitsgemeinschaft f r Evangelische Schwerh rigenseelsorge e V in Verbindung mit dem Deutschen Schwerh rigenbund e V Text P Drews und Arbeitsgruppe an der Schwerh rigenschule Hamburg no year Der Verst rkerausgang wird ber einen Transformator unmittelbar mit der den Raum umgebenden Induktionsschleife verbunden Kurt Eggenschwiler Karl Baschnagel Aktuelle Aspekte der Kirchenakustik in Schweizer Ingenieur und Architekt volume 117 Nr 25 25 June 1999 p 563 Der weit verbreitete Schleifentrafo hat heute ausgedient Ein ausgeglichener Klang vor allem in den hohen f r die Sprachverst ndlichkeit wichtigen Frequenzen kann nur erreicht werden wenn das Sprachsignal mit einem Stromverst rker mit AGC Automatic Gain Control mit Bandpassfilter und einer allf lligen Kompensationsm glichkeit der Armierungseisenverluste in die Induktionsschleife eingespeist wird 38 Deutscher Schw
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