EN 61094-8:2012
(Main)Measurement microphones — Part 8: Methods for determining the free-field sensitivity of working standard microphones by comparison
Measurement microphones — Part 8: Methods for determining the free-field sensitivity of working standard microphones by comparison
IEC 61094-8:2012 applicable to working standard microphones meeting the requirements of IEC 61094-4. It describes methods of determining the free-field sensitivity by comparison with a laboratory standard microphone or working standard microphone (where applicable) that has been calibrated according to either; IEC 61094-3; IEC 61094-2; IEC 61094-5; IEC 61094-6; or this part of IEC 61094. Methods performed in an acoustical environment that is a good approximation to an ideal free-field (e.g. a high quality free-field chamber), and methods that use post processing of results to minimise the effect of imperfections in the acoustical environment, to simulate free-field conditions, are both covered by this part of IEC 61094. Comparison methods based on the principles described in IEC 61094-3 are also possible but beyond the scope of this part of IEC 61094.
Messmikrofone — Teil 8: Verfahren zur Ermittlung des Freifeld-Übertragungskoeffizienten von Gebrauchs-Normalmikrofonen nach der Vergleichsmethode
Microphones de mesure — Partie 8: Méthodes pour la détermination de l'efficacité en champ libre par comparaison des microphones étalons de travail
La CEI 61094-8:2012 est applicable aux microphones étalons de travail satisfaisant aux exigences de la CEI 61094-4. Elle décrit des méthodes pour la détermination de l'efficacité en champ libre par comparaison utilisant un microphone étalon de laboratoire ou un microphone étalon de travail (s'il y a lieu) qui a été étalonné d'après les indications d'un des documents suivants: CEI 61094-3; CEI 61094-2; CEI 61094-5; CEI 61094-6; ou a présente partie de la CEI 61094. Les méthodes employées dans un environnement acoustique constituant une bonne approximation d'un champ libre idéal (par exemple une chambre en champ libre de haute qualité) et les méthodes utilisant un post-traitement des résultats pour réduire au maximum l'effet des imperfections de l'environnement acoustique, afin de simuler les conditions d'un champ libre, sont toutes abordées dans la présente partie de la CEI 61094. Des méthodes de comparaison reposant sur les principes décrits dans la 61094-3 peuvent également être utilisées, mais elles sortent du domaine d'application de la présente partie de la CEI 61094.
Elektroakustika - Merilni mikrofoni - 8. del: Metode za primerjalno umerjanje v odprtem prostoru delovnih mikrofonov
Ta del skupine standardov IEC 61094 se uporablja za delovne mikrofone, ki izpolnjujejo zahteve iz standarda IEC 61094-4. Opisuje metode za ugotavljanje občutljivosti v odprtem prostoru s primerjavo z laboratorijskim standardnim mikrofonom ali delovnim mikrofonom (kjer je to primerno), ki je bil umerjen v skladu s:
– standardom IEC 61094-3,
– standardom IEC 61094-2 ali IEC 61094-5, pri čemer so bili uporabljeni faktorji iz standarda IEC/TS 61094-7,
– standardom IEC 61094-6,
– tem delom standarda IEC 61094.
Ta del standarda IEC 61094 zajema metode, ki se izvajajo v akustičnem okolju, ki je dober približek idealnemu prostemu zvočnemu polju (npr. visokokakovostna gluha komora), in metode, pri katerih se rezultati naknadno prilagodijo, da se čim bolj zmanjša učinek nepravilnosti v akustičnem okolju, s čimer se simulirajo pogoji prostega zvočnega polja. Možne so tudi primerjalne metode, ki temeljijo na načelih iz standarda IEC 61094-3, vendar ne spadajo na področje uporabe tega dela standarda IEC 61094.
General Information
Relations
Standards Content (Sample)
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.Elektroakustika - Merilni mikrofoni - 8. del: Metode za primerjalno umerjanje v odprtem prostoru delovnih mikrofonov/Electroacoustique - Microphones de mesure - Partie 8: Méthodes pour l'étalonnage en champ libre par comparaison des microphones étalons de travailElectroacoustics - Measurement microphones - Part 8: Methods for free-field calibration of working standard microphones by comparison33.160.50PriborAccessories17.140.50ElektroakustikaElectroacousticsICS:Ta slovenski standard je istoveten z:EN 61094-8:2012SIST EN 61094-8:2013en01-marec-2013SIST EN 61094-8:2013SLOVENSKI
STANDARD
EUROPEAN STANDARD EN 61094-8 NORME EUROPÉENNE
EUROPÄISCHE NORM November 2012
CENELEC European Committee for Electrotechnical Standardization Comité Européen de Normalisation Electrotechnique Europäisches Komitee für Elektrotechnische Normung
Management Centre: Avenue Marnix 17, B - 1000 Brussels
© 2012 CENELEC -
All rights of exploitation in any form and by any means reserved worldwide for CENELEC members.
Ref. No. EN 61094-8:2012 E
ICS 17.140.50
English version
Electroacoustics -
Measurement microphones -
Part 8: Methods for free-field calibration of working standard microphones by comparison (IEC 61094-8:2012)
Electroacoustique -
Microphones de mesure -
Partie 8: Méthodes pour l'étalonnage en champ libre par comparaison des microphones étalons de travail (CEI 61094-8:2012)
Elektroakustik -
Messmikrofone -
Teil 8: Verfahren zur Ermittlung des Freifeld-Übertragungskoeffizienten von Gebrauchs-Normalmikrofonen nach der Vergleichsmethode (IEC 61094-8:2012)
This European Standard was approved by CENELEC on 2012-10-24. CENELEC members are bound to comply with the CEN/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 CEN-CENELEC Management Centre or to 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 CEN-CENELEC Management Centre has the same status as the official versions.
CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Croatia, Cyprus, the Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. CENELEC [and/or CEN] shall not be held responsible for identifying any or all such patent rights. Endorsement notice The text of the International Standard IEC 61094-8:2012 was approved by CENELEC as a European Standard without any modification. SIST EN 61094-8:2013
- 3 - EN 61094-8:2012 Annex ZA (normative)
Normative references to international publications with their corresponding European publications
The following documents, in whole or in part, are normatively referenced in this document and are indispensable for its application. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
NOTE
When an international publication has been modified by common modifications, indicated by (mod), the relevant EN/HD applies.
Publication Year Title EN/HD Year
IEC 61094-1 - Measurement microphones -
Part 1: Specifications for laboratory standard microphones EN 61094-1 -
IEC 61094-2 - Electroacoustics - Measurement
microphones -
Part 2: Primary method for the pressure calibration of laboratory standard microphones by the reciprocity technique EN 61094-2 -
IEC 61094-3 - Measurement microphones -
Part 3: Primary method for free-field calibration of laboratory standard microphones by the reciprocity technique EN 61094-3 -
IEC 61094-4 - Measurement microphones -
Part 4: Specifications for working standard microphones EN 61094-4 -
IEC 61094-5 - Measurement microphones -
Part 5: Methods for pressure calibration of working standard microphones by comparison EN 61094-5 -
IEC 61094-6 - Measurement microphones -
Part 6: Electrostatic actuators for determination of frequency response EN 61094-6 -
IEC/TS 61094-7 - Measurement microphones -
Part 7: Values for the difference between free-field and pressure sensitivity levels of laboratory standard microphones - -
ISO/IEC Guide 98-3 - Uncertainty of measurement -
Part 3: Guide to the expression of uncertainty in measurement (GUM:1995) - -
ISO 26101 - Acoustics - Test methods for the qualification of free-field environments
- -
IEC 61094-8 Edition 1.0 2012-09 INTERNATIONAL STANDARD NORME INTERNATIONALE Measurement microphones – Part 8: Methods for determining the free-field sensitivity of working standard microphones by comparison
Microphones de mesure – Partie 8: Méthodes pour la détermination de l'efficacité en champ libre par comparaison des microphones étalons de travail
INTERNATIONAL ELECTROTECHNICAL COMMISSION COMMISSION ELECTROTECHNIQUE INTERNATIONALE V ICS 17.140.50 PRICE CODE CODE PRIX ISBN 978-2-83220-380-4
– 2 – 61094-8 © IEC:2012 CONTENTS
FOREWORD . 4 1 Scope . 6 2 Normative references . 6 3 Terms and definitions . 7 4 Reference environmental conditions . 8 5 Principles of free-field calibration by comparison . 8 5.1 General principle . 8 5.2 General principles using sequential excitation . 8 5.3 General principles using simultaneous excitation . 8 6 General requirements . 9 6.1 The test space . 9 6.2 Methods of establishing the free-field . 9 6.2.1 General . 9 6.2.2 Using a test space with sound absorbing surfaces . 9 6.2.3 Time selective methods for obtaining the free-field sensitivity . 10 6.3 The sound source . 10 6.4 Reference microphone . 11 6.5 Monitor microphone . 12 6.6 Test signals . 12 6.7 Configuration for the reference microphone and microphone under test . 13 7 Factors influencing the free-field sensitivity . 13 7.1 General . 13 7.2 Polarizing voltage . 13 7.3 Acoustic centre of the microphone . 13 7.4 Angle of incidence and alignment with the sound source . 14 7.5 Mounting configuration . 14 7.6 Dependence on environmental conditions. 14 8 Calibration uncertainty components . 14 8.1 General . 14 8.2 Sensitivity of the reference microphone . 15 8.3 Measurement of the microphone output . 15 8.4 Differences between the sound pressure applied to the reference microphone and to the microphone under test . 15 8.5 Influence of indirect sound . 15 8.6 Influence of signal processing . 16 8.7 Influence of microphone characteristics and measurement system performance . 16 8.7.1 Microphone capacitance . 16 8.7.2 Measurement system non-linearity . 16 8.7.3 Validation of calibration system . 16 8.8 Uncertainty on free-field sensitivity level . 16 Annex A (informative)
Basic substitution calibration in a free-field chamber . 18 Annex B (informative)
Time selective techniques . 22 Bibliography . 30 SIST EN 61094-8:2013
61094-8 © IEC:2012 – 3 –
Figure A.1 – Illustration of source and receiver setup in a free-field room,
where the monitor microphone has been integrated into the loudspeaker . 18 Figure A.2 – Practical implementation in a hemi-anechoic room
with a source flush-mounted in the floor . 19 Figure A.3 – Examples of loudspeaker sources . 21 Figure B.1 – Illustration of set-up for measurement with time selective techniques . 23
Table 1 – Calibration options for the reference microphone
and associated typical measurement uncertainty . 12 Table 2 – Typical uncertainty components . 17
– 4 – 61094-8 © IEC:2012 INTERNATIONAL ELECTROTECHNICAL COMMISSION ____________
MEASUREMENT MICROPHONES –
Part 8: Methods for determining the free-field sensitivity
of working standard microphones by comparison
FOREWORD 1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising all national electrotechnical committees (IEC National Committees). The object of IEC is to promote international co-operation on all questions concerning standardization in the electrical and electronic fields. To this end and in addition to other activities, IEC publishes International Standards, Technical Specifications, Technical Reports, Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC Publication(s)”). Their preparation is entrusted to technical committees; any IEC National Committee interested in the subject dealt with may participate in this preparatory work. International, governmental and non-governmental organizations liaising with the IEC also participate in this preparation. IEC collaborates closely with the International Organization for Standardization (ISO) in accordance with conditions determined by agreement between the two organizations. 2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international consensus of opinion on the relevant subjects since each technical committee has representation from all interested IEC National Committees.
3) IEC Publications have the form of recommendations for international use and are accepted by IEC National Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any misinterpretation by any end user. 4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications transparently to the maximum extent possible in their national and regional publications. Any divergence between any IEC Publication and the corresponding national or regional publication shall be clearly indicated in the latter. 5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity assessme
...
Questions, Comments and Discussion
Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.