1、AMERICAN NATIONAL STANDARDMEASUREMENT MICROPHONES PART 1: SPECIFICATIONS FORLABORATORY STANDARDMICROPHONESAccredited Standards Committee S1, AcousticsStandards SecretariatAcoustical Society of America120 Wall Street, 32nd FloorNew York, New York 10005-3993ANSI S1.15-1997/Part 1ANSIS1.15-1997Part1The
2、 American National Standards Institute, Inc. (ANSI) is the na-tional coordinator of voluntary standards development and the clear-ing house in the U.S. for information on national and internationalstandards.The Acoustical Society of America (ASA) is an organization of sci-entists and engineers forme
3、d in 1929 to increase and diffuse theknowledge of acoustics and to promote its practical applications.American National StandardMeasurement Microphones Part 1: Specifications for LaboratoryStandard MicrophonesSecretariatAcoustical Society of AmericaApproved 6 June 1997American National Standards Ins
4、titute, Inc.AbstractThis Standard specifies mechanical dimensions and certain electroacoustical characteristics for capacitor(condenser) microphones used as laboratory standards for sound pressure measurements of the highestattainable accuracy. The specifications are intended to ensure that primary
5、calibration by the reciprocitymethod can be readily carried out. This Standard establishes a system to classify laboratory standardmicrophones into a number of types according to their dimensions and properties. This American NationalStandard is comparable to International Standard IEC 61094-1:1992,
6、 Measurement microphones Part 1: Specifications for laboratory standard microphones.ANSI S1.15-1997 Part 1AMERICAN NATIONAL STANDARDS ON ACOUSTICSThe Acoustical Society of America (ASA) provides the Secretariat for AccreditedStandards Committees S1 on Acoustics, S2 on Mechanical Vibration and Shock,
7、S3 on Bioacoustics, and S12 on Noise. These committees have wide represen-tation from the technical community (manufacturers, consumers, and general-interest representatives). The standards are published by the Acoustical Society ofAmerica through the American Institute of Physics as American Nation
8、al Stan-dards after approval by their respective standards committees and the AmericanNational Standards Institute.These standards are developed and published as a public service to providestandards useful to the public, industry, and consumers, and to Federal, State,and local governments.Each of th
9、e Accredited Standards Committees operating in accordance with pro-cedures approved by American National Standards Institute (ANSI) is responsiblefor developing, voting upon, and maintaining or revising its own standards. TheASA Standards Secretariat administers committee organization and activity a
10、ndprovides liaison between the Accredited Standards Committees and ANSI. Afterthe standards have been produced and adopted by the Accredited StandardsCommittees, and approved as American National Standards by ANSI, the ASAStandards Secretariat arranges for their publication and distribution.An Ameri
11、can National Standard implies a consensus of those substantially con-cerned with its scope and provisions. Consensus is established when, in thejudgment of the ANSI Board of Standards Review, substantial agreement hasbeen reached by directly and materially affected interests. Substantial agreementme
12、ans much more than a simple majority, but not necessarily unanimity. Consen-sus requires that all views and objections be considered and that a concertedeffort be made towards their resolution.The use of American National Standards is completely voluntary. Their existencedoes not in any respect prec
13、lude anyone, whether he or she has approved thestandards or not, from manufacturing, marketing, purchasing, or using products,processes, or procedures not conforming to the standards.NOTICE: This American National Standard may be revised or withdrawn at anytime. The procedures of the American Nation
14、al Standards Institute require thataction be taken periodically to reaffirm, revise, or withdraw this Standard.Standards SecretariatAcoustical Society of America120 Wall Street, 32nd FloorNew York, New York 10005-3993Telephone: 11 212 248 0373Telefax: 11 212 248 0146E-mail: asastdsaip.org 1998 by th
15、e Acoustical Society of America. This Standard may not be reproduced inwhole or in part in any form for sale, promotion, or any commercial purpose, or any purposenot falling within the provisions of the Copyright Act of 1976, without prior written permissionof the publisher. For permission, address
16、a request to the Standards Secretariat of theAcoustical Society of America.ContentsPageForeword . ii1 Scope . 12 Normative references . 13 Definitions . 14 Reference environmental conditions 35 Classification of laboratory standard microphones 36 Characteristics of laboratory standard microphones .
17、47 Specifications . 5Tables1 Norminal mechanical dimensions and tolerance limits for thelaboratory standard microphones of figure 1; dimensions inmillimetres 62 Nominal mechanical dimensions and tolerance limits for theground-shield reference configuration of figure 2; dimensionsin millimetres . 73
18、Electroacoustical specifications for laboratory standardmicrophones. 8Figures1 Mechanical configurations of microphones 62 Mechanical attachment to a microphone showing the ground-shieldreference configuration 7iForewordThis Foreword is for information only and is not an integral part of American Na
19、tionalStandard Measurement Microphones Part 1: Specifications for Laboratory StandardMicrophones, ANSI S1.15-1997/Part 1.This American National Standard is comparable to International Standard IEC61094-1:1992, Measurement microphones Part 1: Specifications for labora-tory standard microphones.This S
20、tandard is Part 1 of a series of standards related to measurement micro-phones.Part 2 of this series covers the primary method for pressure calibration of labora-tory standard microphones by the reciprocity technique. Part 3 covers the primarymethod for free-field calibration of laboratory standard
21、microphones by the reci-procity technique. Part 4 provides specifications for working standard micro-phones.This Standard was developed under the jurisdiction of Accredited Standards Com-mittee S1, Acoustics, which has the following scope:Standards, specifications, methods of measurement and test, a
22、nd terminol-ogy, in the fields of physical acoustics including architectural acoustics, elec-troacoustics, sonics and ultrasonics, and underwater sound, but excludingthose aspects which pertain to safety, tolerance, and comfort.At the time this standard was submitted to Accredited Standards Committe
23、e S1,Acoustics, for final approval, the membership was as follows:J. P. Seiler, ChairmanG. S. K. Wong, Vice ChairmanA. Brenig, SecretaryAcoustical Society of America . J.P.SeilerG. S. K. Wong (Alt.)Air-Conditioning and Refrigeration Institute ARI . R.ComparinS. Sanders (Alt.)American Industrial Hygi
24、ene Association AIHA L.H.RoysterJ. F. Meagher (Alt.)AT FAX: 11 212 248 0146, E-mailasastdsaip.org.iiiAmerican National StandardMeasurementMicrophonesPart 1:Specifications forLaboratory StandardMicrophones1 ScopeThis Part 1: specifies mechanical dimensions and certainelectroacoustic characteristics f
25、or condensermicrophones used as laboratory standards forsound pressure measurements of the highestattainable accuracy. The specifications are in-tended to ensure that primary calibration by thereciprocity method can be readily carried out forthe purpose of traceability to national stan-dards. establ
26、ishes a system for classifying labora-tory standard condenser microphones into anumber of types according to their dimensionsand properties in order to facilitate the specifi-cation of calibration methods, the conduct of in-ter-laboratory comparisons involving the cali-bration of the same microphone
27、s in differentlaboratories, and the interchangeability of mi-crophones in a given calibration system.2 Normative referencesThe following Standards contain provisions that,through reference in this text, constitute provisionsof this American National Standard. At the time ofapproval by the American N
28、ational Standards In-stitute, Inc. (ANSI), the editions indicated werevalid. All standards are subject to revision. Partiesto agreements based on this American NationalStandard are encouraged to investigate the possi-bility of applying the most recent editions of theStandards listed below. Informati
29、on on the mostrecent editions is available from the ASA Stan-dards Secretariat.1 ANSI S1.1-1994, American National StandardAcoustical Terminology.2 IEC 50(801): 1994, International Electrotechni-cal VocabularyChapter 801: Acoustics and elec-troacoustics. First edition.3 ASME B1.1:1989, Unified inch
30、screw threads(UN and UNR thread form).3 DefinitionsFor the purposes of this Part 1, the following defi-nitions apply. Definitions for related quantities aregiven in ANSI S1.1 and in IEC 50(801). Boldfacesymbols represent complex quantities.3.1 capacitor condenser microphone. Micro-phone that consist
31、s of a capacitor and whose op-eration depends upon interaction between its elec-tric field and the change of its electrostaticcapacitance when exposed to the pressure of asound wave 8.25 of ANSI S1.1-1994 and IEV 801-06-13.NOTE This Standard only considers capacitor(condenser) microphones operating
32、by a virtuallyconstant charge obtained from an external polarizingvoltage applied from a source of suitably high internalresistance.3.2 laboratory standard microphone. Capaci-tor microphone capable of being calibrated to avery high accuracy by a primary method such asthe closed coupler reciprocity m
33、ethod, and meet-ing certain severe requirements on mechanical di-mensions and electroacoustical characteristics,especially with respect to stability in time and de-pendence on environmental conditions.3.3 open-circuit voltage. Alternating voltageappearing at the electrical output terminals of amicro
34、phone as measured by the insert voltagetechnique when the microphone is attached to theground-shield configuration specified in 7.2, but isotherwise unloaded. Unit, volt (V).NOTE Owing to the capacitive nature of the micro-phone, the voltage at the electrical terminals de-pends on the electrical loa
35、d presented by the me-chanical and electrical attachment of the microphoneto a preamplifier. For this reason, preamplifiers usedfor measuring the open-circuit voltage of a micro-phone should fulfill the requirements of 7.2.3.4 pressure sensitivity of a microphone. Fora sinusoidal signal of given fre
36、quency and forgiven environmental conditions, quotient of theroot-mean-square, open-circuit voltage of the mi-crophone by the root-mean-square sound pres-sure acting over the exposed surface of the dia-phragm (i.e., at the acoustical terminals of theAMERICAN NATIONAL STANDARD ANSI S1.15-1997 Part 11
37、 1998 Acoustical Society of Americamicrophone), the sound pressure being uniformlyapplied over the surface of the diaphragm. Thisquotient is a complex quantity. When phase infor-mation is of no interest, the pressure sensitivitymay denote its modulus only. Unit, volt per pascal(V/Pa).3.5 pressure se
38、nsitivity level of a micro-phone. Logarithm of the ratio of the modulus ofthe pressure sensitivity uMpu to a reference sensi-tivity. Pressure sensitivity level in decibels is 20lg(uMpu/MR), where the reference sensitivity MRis 1V/Pa. Unit, decibel (dB).3.6 free-field sensitivity of a microphone. For
39、a sinusoidal plane progressive wave of given fre-quency, for a specified direction of sound inci-dence, and for given environmental conditions,quotient of the root-mean-square, open-circuit out-put voltage of the microphone by the root-mean-square sound pressure that would exist at the po-sition of
40、the acoustic center of the microphone inthe absence of the microphone. This quotient is acomplex quantity. When phase information is of nointerest, the free-field sensitivity may denote itsmodulus only. Unit, volt per pascal (V/Pa).NOTES1 At frequencies sufficiently low for the distur-bance of the s
41、ound field by the microphone to benegligible, the free-field sensitivity approaches thepressure sensitivity; see 6.10 for practical limitations.2 The position of the acoustic center is a functionof frequency.3.7 free-field sensitivity level of a micro-phone. Logarithm of the ratio of the modulus oft
42、he free-field sensitivity uMfu to a reference sensitiv-ity. Free-field sensitivity level in decibels is 20lg(uMfu/MR), where the reference sensitivity MRis 1V/Pa. Unit, decibel (dB).3.8 diffuse-field sensitivity of a microphone.For a sinusoidal signal of specified frequency andfor given environmenta
43、l conditions, quotient of theroot-mean-square, open-circuit output voltage ofthe microphone as a result of sound waves arrivingmore-or-less simultaneously with equal probabilityfrom all directions, by the root-mean-square soundpressure, from the same sound waves, at the po-sition of the acoustic cen
44、ter of the microphone inthe absence of the microphone. Unit, volt per pas-cal (V/Pa).NOTES1 At frequencies sufficiently low for the distur-bance of the sound field by the microphone to benegligible, the diffuse-field sensitivity approaches thepressure sensitivity; see 6.10 for practical limitations.
45、2 The position of the acoustic center is a functionof frequency3.9 diffuse-field sensitivity level of a micro-phone. Logarithm of the ratio of the modulus ofthe diffuse-field sensitivity uMdu to a reference sen-sitivity. Diffuse-field sensitivity level in decibels is20 lg(uMdu/MR), where the referen
46、ce sensitivity MRis 1 V/Pa. Unit, decibel (dB).3.10 random-incidence sensitivity of a micro-phone. For a sinusoidal signal of specified fre-quency and for given environmental conditions, ata specified location, quotient of the root-mean-square, open-circuit output voltage of the micro-phone as a res
47、ult of a succession of sound wavesincident with equal probability from all directions,by the root-mean-square sound pressure at theposition of the acoustic center of the microphonefrom a single free sound wave in the absence ofthe microphone. Unit, volt per pascal (V/Pa).3.11 random-incidence sensit
48、ivity level of amicrophone. Logarithm of the ratio of the modu-lus of the random-incidence sensitivity uMriu to areference sensitivity. Random-incidence sensitivitylevel in decibels is 20 lg(uMriu/MR), where the refer-ence sensitivity MRis 1 V/Pa. Unit, decibel (dB).NOTE From the best of the availab
49、le experimentalevidence, taken under nearly ideal conditions in agiven laboratory, for a given microphone, diffuse-fieldand random-incidence sensitivity levels, at frequen-cies as high as 12.5 kHz, agreed within approxi-mately 0.1 dB or by an amount comparable to theuncertainty of the measurements. The two sensitivitylevels are used equivalently for the purposes of thisStandard.3.12 electrical impedance of a microphone.For a sinusoidal signal of given frequency, com-plex quotient of the voltage applied across the mi-crophones electrical terminals by t
