BS EN 60645-3-2007 Electroacoustics - Audiometric equipment - Test signals of short duration《电声学 听力测定设备 短时持续试验信号》.pdf

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1、 g49g50g3g38g50g51g60g44g49g42g3g58g44g55g43g50g56g55g3g37g54g44g3g51g40g53g48g44g54g54g44g50g49g3g40g59g38g40g51g55g3g36g54g3g51g40g53g48g44g55g55g40g39g3g37g60g3g38g50g51g60g53g44g42g43g55g3g47g36g58Part 3: Test signals of short durationThe European Standard EN 60645-3:2007 has the status of a Bri

2、tish StandardICS 13.140; 17.140.50Electroacoustics Audiometric equipment BRITISH STANDARDBS EN 60645-3:2007BS EN 60645-3:2007This British Standard was published under the authority of the Standards Policy and Strategy Committee on 31 August 2007 BSI 2007ISBN 978 0 580 54505 4Amendments issued since

3、publicationAmd. No. Date CommentsThis publication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application.Compliance with a British Standard cannot confer immunity from legal obligations.National forewordThis British Standard is the U

4、K implementation of EN 60645-3:2007. It is identical to IEC 60645-3:2007. It supersedes BS EN 60645-3:1995 which is withdrawn. The UK participation in its preparation was entrusted to Technical Committee EPL/29, Electroacoustics.A list of organizations represented on this committee can be obtained o

5、n request to its secretary.EUROPEAN STANDARD EN 60645-3 NORME EUROPENNE EUROPISCHE NORM July 2007 CENELEC European Committee for Electrotechnical Standardization Comit Europen de Normalisation Electrotechnique Europisches Komitee fr Elektrotechnische Normung Central Secretariat: rue de Stassart 35,

6、B - 1050 Brussels 2007 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members. Ref. No. EN 60645-3:2007 E ICS 17.140.50 Supersedes EN 60645-3:1995English version Electroacoustics - Audiometric equipment - Part 3: Test signals of short duration (IEC 6

7、0645-3:2007) Electroacoustique - Equipements audiomtriques - Partie 3: Signaux dessai de courte dure (CEI 60645-3:2007) Akustik - Audiometer - Teil 3: Kurzzeit-Hrprfsignale (IEC 60645-3:2007) This European Standard was approved by CENELEC on 2007-06-01. CENELEC members are bound to comply with the C

8、EN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the Central Secretariat or t

9、o any CENELEC member. This European Standard exists in three official versions (English, French, German). A version in any other language made by translation under the responsibility of a CENELEC member into its own language and notified to the Central Secretariat has the same status as the official

10、 versions. CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Cyprus, the Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Ro

11、mania, Slovakia, Slovenia, Spain, Sweden, Switzerland and the United Kingdom. Foreword The text of document 29/595/CDV, future edition 2 of IEC 60645-3, prepared by IEC TC 29, Electroacoustics, was submitted to the IEC-CENELEC parallel Unique Acceptance Procedure and was approved by CENELEC as EN 60

12、645-3 on 2007-06-01. This European Standard supersedes EN 60645-3:1995. Specific changes in EN 60645-3:2007 concern new figures of reference signals and changes in definitions. The following dates were fixed: latest date by which the EN has to be implemented at national level by publication of an id

13、entical national standard or by endorsement (dop) 2008-03-01 latest date by which the national standards conflicting with the EN have to be withdrawn (dow) 2010-06-01 This European Standard has been prepared under a mandate given to CENELEC by the European Commission and the European Free Trade Asso

14、ciation and covers essential requirements of EC Directive MDD (93/42/EEC). See Annex ZZ. Annexes ZA and ZZ have been added by CENELEC. _ Endorsement notice The text of the International Standard IEC 60645-3:2007 was approved by CENELEC as a European Standard without any modification. _ 2 EN 60645-3:

15、2007CONTENTS INTRODUCTION.4 1 Scope .5 2 Normative references .5 3 Terms and definitions .6 4 General requirements .9 5 Reference signals .9 5.1 General .9 5.2 Reference pulse 9 5.3 Reference tone-burst.10 6 Calibration and measurement of short-duration signals 10 7 Instruction manual 11 BibIiograph

16、y .12 Figure 1 Temporal characteristics of an electric reference pulse 8 Figure 2 Illustration of the method of measurement of peak-to-peak equivalent signal levels 8 Figure 3 Temporal characteristics of an electrical reference tone-burst 9 3 EN 60645-3:2007Annex ZA (normative) Normative references

17、to international publications with theircorresponding European publications .13 Annex ZZ (informative) Coverage of Essential Requirements of EC Directives .14 INTRODUCTION Developments in the field of hearing measurements for diagnostic, hearing conservation and rehabilitation purposes have resulted

18、 in the availability of a wide range of audiometers. In addition it is possible to consider the audiometer in terms of a set of functional units that can be specified independently. By specifying these functional units it is then possible to specify the performance of other audiometric equipment tha

19、t uses these units. IEC 60645, Electroacoustics Audiometric equipment, consists of a number of parts. Part 3 covers the requirements for reference and other test signals of short duration. Examples of test methods, where such signals are commonly used, are the recording of brainstem evoked potential

20、s and evoked otoacoustic emissions. Reference signals are described in order to provide a basis for calibration and as a recommendation for use when there is no specific reason to have an alternative signal. The method of measurement of acoustic and vibratory signals is described. 4 EN 60645-3:2007E

21、LECTROACOUSTICS AUDIOMETRIC EQUIPMENT Part 3: Test signals of short duration 1 Scope This part of IEC 60645 specifies a means of describing the physical characteristics of audiometric reference and test signals of short duration and methods for their measurement. The object of this standard is to en

22、sure that audiometric stimuli of short duration are specified and measured in the same way and that the calibration of equipment using such signals is carried out using defined methods. This standard does not describe the method of use of short duration test signals. 2 Normative references The follo

23、wing referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. IEC 60318-1, Electroacoustics Simulators of human head and

24、 ear Part 1: Ear simulator for the calibration of supra-aural earphones IEC 60318-3, Electroacoustics Simulators of human head and ear Part 3: Acoustic coupler for the calibration of supra-aural earphones used in audiometry IEC 60318-5, Electroacoustics Simulators of human head and ear Part 5: 2 cm3

25、coupler for the measurement of hearing aids and earphones coupled to the ear by means of ear inserts IEC 60318-6, Electroacoustics Simulators of human head and ear Part 6: Mechanical coupler for the measurements on bone vibrators 1)IEC 60645-1:2001, Electroacoustics Audiological equipment Part 1: Pu

26、re-tone audiometers IEC 60711, Occluded-ear simulator for the measurement of earphones coupled to the ear by ear inserts 2)ISO 389-6, Acoustics Reference zero for the calibration of audiometric equipment Part 6: Reference equivalent threshold sound pressure levels for acoustic test signals of short

27、duration 3) 1)To be published (revision of IEC 60373). 2) Will be published later as IEC 60318-4. 3)To be published. 5 EN 60645-3:20073 Terms and definitions For the purposes of this document, the following terms and definitions apply: 3.1 short-duration signal signal having a duration of less than

28、200 ms 3.2 click transient acoustic or vibratory signal whose frequency spectrum covers a broad frequency range, produced by applying a single rectangular electrical pulse to the terminals of the transducer NOTE See Figures 1 and 2. 3.3 tone-burst sinusoidal signal having a duration of less than 200

29、 ms NOTE 1 Figure 3 shows a reference tone-burst (see 5.3). NOTE 2 A tone-burst is sometimes called a brief tone or a tone pip. 3.4 condensation signal short-duration signal, the initial sound pressure wave of which causes an over-pressure relative to ambient pressure, or the initial vibratory force

30、 wave of which causes an over-force relative to the static force at the plane of the output port of the transducer 3.5 rarefaction signal short duration signal, the initial sound pressure wave of which causes an under-pressure relative to ambient pressure, or the initial vibratory force wave of whic

31、h causes an under-force relative to the static force at the plane of the output port of the transducer 3.6 alternating polarity signal series of short-duration signals, consisting of rarefaction and condensation signals in alternating order 3.7 initial sound pressure or vibratory force wave of a cli

32、ck first half wave of sound pressure or vibratory force, the amplitude of which is larger than 0,5 times the amplitude of the next half wave with opposite polarity 3.8 duration of initial sound pressure or vibratory force wave of a click time interval between the two zero crossings of the initial so

33、und pressure or vibratory force wave 6 EN 60645-3:20073.9 duration of a tone-burst time interval between the half maximum amplitude points on the rising and falling portions of the envelope of the tone-burst NOTE See Figure 3 (key 4). 3.10 rise and fall times of a tone-burst time intervals between t

34、he 10 % and 90 % amplitude points of the rising portion and the 90 % and 10 % amplitude points on the falling portion of the envelope of the tone-burst NOTE See Figure 3 (keys 3 and 5). 3.11 peak-to-peak equivalent signal level r.m.s value of a long duration sinusoidal signal which, when compared un

35、der the same test conditions with a short duration output signal from the transducer under test, has the same peak-to-peak value (i.e. difference between the extreme positive and the extreme negative values) as the short duration signal NOTE 1 See Figure 2. NOTE 2 Both the short and the long duratio

36、n signals are measured by means of an ear simulator, or a free-field microphone, or a mechanical coupler, respectively. NOTE 3 For clicks, the long duration sinusoidal signal should have a frequency of 1 000 Hz, and for tone-bursts its frequency should equal the fundamental frequency of the tone-bur

37、st. NOTE 4 The equivalence in this definition is between two different signals. When short duration signals are standardised as sound pressure levels or vibratory force levels for hearing threshold purposes a further equivalence occurs (see 6.6) due to the method of measuring hearing thresholds and

38、storing the data from those measurements in an ear simulator, that is in terms of equivalent threshold vibratory force or sound pressure levels. NOTE 5 The term peak-to-peak equivalent signal level is often called peak equivalent signal level. NOTE 6 The peak level of a short duration signal is anyw

39、here between 3 dB and 9 dB greater than the peak-to-peak equivalent level, i.e. 3 dB when the signal is quite symmetrical around the zero baseline and 9 dB when it is completely on one side of the zero level. NOTE 7 The recommended abbreviations for peak-to-peak equivalent sound pressure level and v

40、ibratory force level are peSPL and peVFL. 7 EN 60645-3:20071 2100 s IEC 354/07Key 1 Level 2 Time Figure 1 Temporal characteristics of an electric reference pulse 1 2 IEC 355/07 Key 1 Level 2 Time Figure 2 Illustration of the method of measurement of peak-to-peak equivalent signal levels The left par

41、t of the figure shows an example of the acoustic click signal generated by an electric rectangular pulse applied to a transducer (100 s electric pulse fed to a TDH-39 earphone with MX-41/AR cushion and measured on an ear simulator IEC 60318-1) and the right part presents the long duration sinusoidal

42、 signal. 8 EN 60645-3:20071 3 452 1,0 0,9 0,5 0,1 0 0,5 1,0 IEC 356/07 Key 1 Level 2 Time 3 Rise time 4 Duration 5 Fall time Figure 3 Temporal characteristics of an electrical reference tone-burst 4 General requirements Equipment using short duration signals shall meet the requirements of IEC 60645-

43、1:2001 as appropriate. 5 Reference signals 5.1 General The following reference signals are described for the purposes of standardization. 5.2 Reference pulse The reference pulse (see Figure 1) shall be an electric rectangular pulse (single monophasic rectangular wave) of (100 10) s duration with ris

44、e and fall times less than 25 s. NOTE 1 The same definition of rise-/fall times and duration as given in Figure 3 applies to the reference pulse. NOTE 2 The signal output of the transducer may vary considerably depending upon the type used. 9 EN 60645-3:20075.3 Reference tone-burst The reference ton

45、e-burst shall be an electrical signal consisting of five periods of the fundamental sine wave and having a linear rise and fall. The tone-burst shall have 1,6 periods of rise and fall time, and duration of three periods as defined in Figure 3. NOTE 1,6 periods of linear rise or fall corresponds to t

46、wo periods from zero to 100 % amplitude. The signal envelope remains at the 100 % amplitude for one period. The reference tone-burst may also be described according to the 2-1-2 concept where 2 indicates the number of periods from zero to 100 % amplitude and back to zero and 1 is the 100 % amplitude

47、 period. 6 Calibration and measurement of short-duration signals 6.1 For each signal type the following characteristics of an instrument generating signals of short duration shall be measured and reported by the manufacturer. type of reference signal used; type of transducer and associated type of e

48、ar simulator, mechanical coupler or sound level meter used and the method of coupling the transducer to the measurement system; level measured in dB in terms of peak-to-peak equivalent sound pressure level or peak-to-peak equivalent vibratory force level; polarity of electric output signal (i.e. pos

49、itive (condensation), negative (rarefaction), alternating or random initial phase). the shape of the envelope rise and fall (linear, cos2, hanning etc.). NOTE The polarity of the measuring system including its transducer has to be known in order to identify the polarity of the acoustic or vibratory signal. 6.2 The equipment shall be calibrated using reference signals defined in Clause 5. Where other signals are used,