scope:

This report describes a head and torso simulator (manikin) which reproduces approximately the acoustical effects of a median human adult, including diffraction affecting the performance of a hearing aid on a person. 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 on a median human adult.

Notes 1. - Measurement results obtained with the manikin may differ substantially from similar results obtained on an individual person, due to anatomical variations.

2.- The median values were drawn from the population samples described in the bibliography (see Appendix C).

The manikin is described physically as well as acoustically, and requirements are specified for both descriptions.

The device described in this report is provisional, pending further investigations which might result in a geometrically simpler device without jeopardizing the accuracy of hearing aid measurements.