1、 ANSI S1.15-2005/Part 2 AMERICAN NATIONAL STANDARD Measurement Microphones Part 2: Primary Method for Pressure Calibration of Laboratory Standard Microphones by the Reciprocity Technique Accredited Standards Committee S1, Acoustics Standards Secretariat Acoustical Society of America 35 Pinelawn Road
2、, Suite 114 E Melville, NY 11747-3177ANSI S1.15-2005/Part 2 Reaffirmed by ANSI June 2, 2010 Reaffirmed by ANSI May 13, 2015 The American National Standards Institute, Inc. (ANSI) is the national coordinator of voluntary standards development and the clearinghouse in the U.S.A. for information on nat
3、ional and international standards. The Acoustical Society of America (ASA) is an organization of scientists and engineers formed in 1929 to increase and diffuse the knowledge of acoustics and to promote its practical applications. ANSI S1.15- 2005 /Part 2 (Replaces ANSI S1.10-1966) AMERICAN NATIONAL
4、 STANDARD Measurement Microphones Part 2: Primary Method for Pressure Calibration of Laboratory Standard Microphones by the Reciprocity Technique Secretariat Acoustical Society of America Approved by: American National Standards Institute, Inc. 9 March 2005 Abstract This Standard specifies a primary
5、 method for the calibration of microphones by the reciprocity technique. The specifications are intended to ensure that primary calibration with the reciprocity technique can attain the highest accuracy. The technical requirements of this American National Standard is identical to International Stan
6、dard IEC 61094-2: 1992, “Measurement microphones - Part 2: Primary method for pressure calibration of laboratory standard microphones by the reciprocity technique“. Various improvements have been made to include recent technical information. 2 AMERICAN NATIONAL STANDARDS ON ACOUSTICS The Acoustical
7、Society of America (ASA) provides the Secretariat for Accredited Standards Committees S1 on Acoustics, S2 on Mechanical Vibration and Shock, S3 on Bioacoustics, and S12 on Noise. These committees have wide representation from the technical community (manufacturers, consumers, trade associations, org
8、anizations with a general interest, and government representatives). The standards are published by the Acoustical Society of America as American National Standards after approval by their respective Standards Committees and the American National Standards Institute. These standards are developed an
9、d published as a public service to provide standards useful to the public, industry, and consumers, and to Federal, State, and local governments. Each of the accredited Standards Committees operating in accordance with procedures approved by American National Standards Institute (ANSI) is responsibl
10、e for developing, voting upon, and maintaining or revising its own Standards. The ASA Standards Secretariat administers Committee organization and activity and provides liaison between the Accredited Standards Committees and ANSI. After the Standards have been produced and adopted by the Accredited
11、Standards Committees, and approved as American National Standards by ANSI, the ASA Standards Secretariat arranges for their publication and distribution. An American National Standard implies a consensus of those substantially concerned with its scope and provisions. Consensus is established when, i
12、n the judgment of the ANSI Board of Standards Review, substantial agreement has been reached by directly and materially affected interests. Substantial agreement means much more than a simple majority, but not necessarily unanimity. Consensus requires that all views and objections be considered and
13、that a concerted effort be made towards their resolution. The use of an American National Standard is completely voluntary. Their existence does not in any respect preclude anyone, whether he or she has approved the Standards or not, from manufacturing, marketing, purchasing, or using products, proc
14、esses, or procedures not conforming to the Standards. NOTICE: This American National Standard may be revised or withdrawn at any time. The procedures of the American National Standards Institute require that action be taken periodically to reaffirm, revise, or withdraw this Standard. Acoustical Soci
15、ety of America ASA Secretariat 35 Pinelawn Road, Suite 114E Melville, New York 11747-3177 Telephone: 1 (631) 390-0215 Fax: 1 (631) 390-0217 E-mail: asastdsaip.org 2005 by Acoustical Society of America. This standard may not be reproduced in whole or in part in any form for sale, promotion, or any co
16、mmercial purpose, or any purpose not falling within the provisions of the U.S. Copyright Act of 1976, without prior written permission of the publisher. For permission, address a request to the Standards Secretariat of the Acoustical Society of America.iContents 1 Scope 1 2 Normative references 1 3
17、Definitions 1 4 Reference environmental conditions. 2 5 Principles of pressure calibration by reciprocity 3 5.1 General principle 3 5.2 Basic expressions 3 5.3 Insert voltage technique. 4 5.4 Evaluation of the acoustic transfer impedance 5 5.5 Heat-conduction correction 7 5.6 Capillary tube correcti
18、on 7 5.7 Final expressions for the pressure sensitivity 8 6 Factors influencing the pressure sensitivity 8 6.1 General 8 6.2 Polarizing voltage. 9 6.3 Ground shield reference configuration. 9 6.4 Pressure distribution over the diaphragm 9 6.5 Dependence on environmental conditions. 10 7 Calibration
19、uncertainty components 10 7.1 General 10 7.2 Electrical transfer impedance. 11 7.3 Acoustical transfer impedance. 11 7.4 Polarizing voltage. 13 7.5 Uncertainty on pressure sensitivity level 13 Annex A (normative) Heat conduction in a closed cavity . 17 A.1 14 A.2 Bibliography for Annex A . 15 Annex
20、B (normative) Acoustic impedance of a capillary tube 17 B.1 Determination by the transmission line theory. 17 B.2 Bibliography for Annex B . 18 Annex C (informative) Examples of cylindrical couplers for calibration of microphones 21 ii C.1 General 21 C.2 Plane-wave couplers 21 C.3 Large-volume coupl
21、ers 23 C.4 Bibliography for Annex C . 24 Annex D (informative) Environmental influence on the sensitivity of microphones . 25 D.1 General 25 D.2 Dependence on static pressure . 25 D.3 Microphone sensitivity pressure correction 26 D.4 Dependence on temperature . 28 D.5 Bibliography for Annex D . 30 A
22、nnex E (informative) Methods for determining microphone parameters 31 E.1 Introduction 31 E.2 Front cavity depth 31 E.3 Front cavity volume and equivalent volume. 31 E.4 Acoustic impedance of the microphone. 32 Annex F (informative) Physical properties of air 33 F.1 Properties. 33 F.2 Nomenclature:
23、33 F.3 Density of humid air . 34 F.4 Speed of sound in air. 35 F.5 Ratio of specific heats of air. 37 F.6 Viscosity and thermal diffusivity of air for capillary correction . 37 F.7 Bibliography for Annex F 39 Annex G (informative) A numerical example for the calculation of estimated expanded uncerta
24、inty41 Bibliography 43 Tables Table A.1 Values for Ev. 16 Table B.1a Real part of Za,C in gigapascal-second per cubic metre (GPag152sg152m-3). 19 Table B.1b Imaginary part of Za,Cin gigapascal-second per cubic metre (GPag152sg152m-3) . 20 Table C.1 Nominal dimensions for plane-wave couplers . 22 Tab
25、le C.2 Nominal dimensions and tolerances for large-volume couplers 24 iiiTable C.3 Experimentally determined wave-motion corrections for the air-filled large-volume coupler used with type LS1P microphones 24 Table D.1Coefficients of the polynomial for calculating the microphone sensitivity pressure
26、corrections using Equations (D.1) or (D.2), and temperature corrections using Equation (D.3) for Brel and Kjr Type 4160 and Type 4180 microphones 30 Table F.1 Coefficient constants F.6 for the computation of c/coand g539/g539o. 38 Table F2 Recommended values of the quantities in clauses F.1 F.5 38 T
27、able F3 Recommended reference values applicable to dry air at 0 0C and 101.325 kPa 38 Table G.1 A numerical example for the calculation of estimated expanded uncertainty of microphone sensitivity level with a particular microphone calibration arrangement at 250 Hz 41 Figures Figure 1 Equivalent circ
28、uit for evaluating the acoustic transfer impedance Za,1 . 5 Figure 2 Equivalent circuit for evaluating Zg99a,12 when coupler dimensions are small compared with wavelength . 6 Figure 3 Equivalent circuit for evaluating Zg99a,12, when plane wave transmission in the coupler can be assumed 7 Figure C.1
29、Mechanical configuration of plane-wave couplers 22 Figure C.2 Mechanical configuration of large-volume couplers 23 Figure D.1 Examples of static pressure coefficient of LS1P and LS2P microphones relative to the low-frequency value as a function of relative frequency f/fo. 26 Figure D.2 The variation
30、 of the slopes of sensitivity correction curves with frequency for three Brel and Kjr Type 4160 microphones. The curve is obtained with an empirical equation for the computation of microphone sensitivity pressure correction. See Eq. (D.1). 27 Figure D.3 General frequency dependence of that part of t
31、he temperature coefficient for LS1P and LS2P microphones caused by the variation in the impedance of the enclosed air 28 iv Foreword This Foreword is for information only, and is not a part of the American National Standard ANSI S1.15 - 200X/Part 2 American National Standard American National Standa
32、rd Measurement Microphones Part 2: Primary Method for Pressure Calibration of laboratory Standard Microphones by the Reciprocity Technique. This standard comprises a part of a group of definitions, standards, and specifications for use in acoustics. It was developed and approved by Accredited Standa
33、rds Committee S1 Acoustics, under its approved operating procedures. Those procedures have been accredited by the American National Standards Institute (ANSI). The Scope of Accredited Standards Committee S1 is as follows: Standards, specifications, methods of measurement and test, and terminology in
34、 the field of physical acoustics, including architectural acoustics, electroacoustics, sonics and ultrasonics, and underwater sound, but excluding those aspects which pertain to biological safety, tolerances, and comfort. The technical requirements in this American National Standard are identical to
35、 the international standard IEC 61094-2 1992-03, Measurement Microphones Part 2: Primary Method for Pressure Calibration of Laboratory Standard Microphones by the Reciprocity Technique. Various improvements have been made to include the latest information on pressure and temperature coefficients for
36、 microphone sensitivity correction and physical properties of air. This standard replaces ANSI S1.10-1966 American National Standard Method for the Calibration of Microphones. Annexes A and B form an integral part of this standard. Annexes C, D, E, F, and G are for information only. At the time this
37、 Standard was submitted to Accredited Standards Committee S1, Acoustics for approval, the membership was as follows: J.P. Seiler, Chair G.S.K. Wong, Vice-Chair S.B. Blaeser, Secretary Acoustical Society of America.G.S.K. Wong . J. Seiler (Alt.) Air-Conditioning and Refrigeration Institute .R. Seel A
38、merican Industrial Hygiene Association. D. Driscoll D. Sandfort (Alt.) Audio Engineering Society, Inc. M.R. Chial Brel FAX: 631-390-0217; E-mail: asastdsaip.org AMERICAN NATIONAL STANDARD ANSI S1.15-2005/Part 2 1American National Standard Measurement Microphones Part 2: Primary Method for Pressure C
39、alibration of Laboratory Standard Microphones by the Reciprocity Method 1 Scope This standard g127 is applicable to laboratory standard microphones meeting the requirements of ANSI S1.15-1997/Part 1 (R2001) and other types of condenser microphones having the same mechanical dimensions; g127 specifie
40、s a primary method of determining the pressure sensitivity to establish a reproducible and accurate basis for the measurement of sound pressure. 2 Normative references The following referenced documents are indispensable for the application of this standard. For dated references, only the edition ci
41、ted applies. For undated references, the latest edition of the referenced document (including any amendments) applies. ANSI S1.1-1994 (R 1999) American National Standard Acoustical Terminology. ANSI S1.15-1997/Part 1 (R2001), American National Standard Measurement microphones Part 1: Specifications
42、for Laboratory Standard Microphones. ANSI/IEEE 260.4-1996 (R2002) American National Standard Letter Symbols and Abbreviations for Quantities Used in Acoustics. IEC 60050-801:1994 International electrotechnical vocabulary Chapter 801: Acoustics and electroacoustics. Guide to the expression of uncerta
43、inty in measurement, 1995, BIPM, IEC, IFCC, ISO, IUPAC, IUPAP, OILM 3 Definitions For the purposes of this standard, the terms and definitions given in ANSI S1.1:1994. IEC 60050-810:1994, and ANSI/IEEE 260.45-1996 (R2002), and the following apply NOTE Boldface symbols represents complex quantities.
44、ANSI S1.15-2005/Part 2 2 3.1 reciprocal microphone A linear passive microphone for which the open-circuit reverse and forward transfer impedances are equal in magnitude. 3.2 phase angle of pressure sensitivity of a microphone For a given frequency, the phase angle between the open-circuit voltage an
45、d the uniform sound pressure acting on the diaphragm. Unit: degree or radian (oor rad). 3.3 electrical transfer impedance For a system of two acoustically coupled microphones the quotient of the open-circuit voltage of the microphone used as a receiver by the input current through the electrical ter
46、minals of the microphone used as a transmitter. Unit: ohm (g58). NOTE This impedance is defined for the ground-shield configuration given in 7.2 of ANSI S1.15-1997/Part 1 (R2001). 3.4 acoustic transfer impedance For a system of two acoustically coupled microphones the quotient of the sound pressure
47、acting on the diaphragm of the microphone used as a receiver by the short-circuit volume velocity produced by the microphone used as a transmitter. Unit: pascal-second per cubic metre (Pag152s.m-3). 3.5 coupler A device which, when fitted with microphones, forms a cavity of predetermined shape and d
48、imensions acting as an acoustic coupling element between the microphones. 4 Reference environmental conditions The reference environmental conditions are: Temperature: tr= 23.0 oC Static pressure: ps,r= 101.325 kPa Relative humidity: Hr = 50% ANSI S1.15-2005/Part 2 35 Principles of pressure calibrat
49、ion by reciprocity 5.1 General principle A reciprocity calibration of microphones may be carried out by means of three microphones, two of which shall be reciprocal, or by means of an auxiliary sound source and two microphones, one of which must be reciprocal. NOTE If one of the microphones is not reciprocal it can only be used as a sound receiver. 5.1.1 General principles using three microphones Let two of the microphones be connected acoustically by a coupler. Using one of them as a sound source and the other as a sound