Abstract
IEC/TS 60318-7:2011(E) describes a head and torso simulator (manikin) intended for the measurement of air-conduction hearing aids in the frequency range from 100 Hz to 10 000 Hz. The device consists of a head mounted on a torso that extends to the waist. The head is equipped with simulated pinnae and with cylindrical cavities having acoustic impedance terminations and microphones located at positions corresponding to those of the eardrums in a median human adult. It has been designed to provide acoustic diffraction similar to that encountered around the median human head and torso. The device with its present pinna simulator, however, is not suitable for the measurement of all types of hearing aids. For example, most in-the-ear (ITE) and completely-in-the-canal (CIC) hearing aids cannot be measured correctly. The manikin is specified in terms of both, its geometrical dimensions and its acoustical properties. IEC/TS 60318-7:2011 has been developed as a revision of IEC/TR 60959 (1990). The main changes, as compared to the technical report, are the insertion of maximum permitted expanded measurement uncertainties and additional references in the Bibliography. A future IEC Standard which will include additional models of head and torso simulators for hearing aid measurements is planned.
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