Historical
IEC 60711 Ed. 1.0 b:1981
Occluded-ear simulator for the measurement of earphones coupled to the ear by ear inserts
Specifies an occluded-ear simulator, intended for the calibration of insert earphones in the frequency range 100 Hz to 10 000 Hz in terms of the sound pressure at the eardrum.
International Electrotechnical Commission [iec]