IEC 61094-1:2000 pdf download.Microphones de mesure
1 Scope
This part of IEC 61094 specifies mechanical dimensions and certain electroacoustic characteristics for condenser microphones used as laboratory standards for the realization of the unit of sound pressure and for sound pressure measurements of the highest attainable accuracy. The specifications are intended to ensure that primary calibration by the reciprocity method can be readily carried out.
This part also establishes a system for classifying laboratory standard condenser micro-phones into a number of types according to their dimensions and properties in order to facilitate the specification of calibration methods, the conducting of inter-laboratory comparisons involving the calibration of the same microphones in different laboratories, and the interchangeability of microphones in a given calibration system.
2 Normative references
The following normative documents contain provisions which, through reference in this text,constitute provisions of this part of IEC 61094. For dated references， subsequent amendments to, or revisions of, any of these publications do not apply. However partiest agreements based on this part of IEC 61094 are encouraged to investigate the possibility of applying the most recent editions of the normative documents indicated below. For undated references, the latest edition of the normative document referred to applies. Members of ISO and IEC maintain registers of currently valid International Standards.
3.2 laboratory standard microphone
condenser microphone capable of being calibrated to a very high accuracy by a primary method such as the closed coupler reciprocity method, and meeting certain severe requirements on mechanical dimensions and electroacoustical characteristics, especially with respect to stability in time and dependence on environmental conditions
3.3 open-circuit voltage
alternating voltage appearing at the electrical output terminals of a microphone as measured by the insert voltage technique when the microphone is attached to the ground shield configuration specified in 7.2 but is otherwise unloaded
Unit: volt, V
NOTE Owing to the capacitive nature of the microphone, the voltage at the electrical terminals depends on the electrical load presented by the mechanical and electrical attachment of the microphone to a preamplifier. For this reason,preamplifiers used for measuring the open-circuit voltage of a microphone should fulfill the requirements of 7.2.
3.4 pressure sensitivity of a microphone
for a sinusoidal signal of given frequency and for given environmental conditions, the quotient of the open-circuit voltage of the microphone by the sound pressure acting over the exposed surface of the diaphragm (i.e. at the acoustical terminals of the microphone)， the sound pressure being uniformly applied over the surface of the diaphragm. This quotient is a complex quantity, but when phase information is of no interest the pressure sensitivity may denote its modulus only
Unit: volt per pascal, V/Pa.IEC 61094-1 pdf download.