Historical
IEC 60318-3 Ed. 1.0 b:1998
Electroacoustics - Simulators of human head and ear - Part 3: Acoustic coupler for the calibration of supra-aural earphones used in audiometr
Describes an acoustic coupler for loading supra-aural audiometric earphones as specified in ISO 389 with a specified acoustic impedance, when calibrating audiometers, in the frequency range of 125 Hz to 8 000 Hz.
International Electrotechnical Commission [iec]