KEMAR (source code)
= KEMAR
{c}
\b[KEMAR], the Knowles Electronics Manikin for Acoustic Research, is a head-and-torso acoustic simulator used to measure how sound interacts with an approximately human-sized listening geometry. Its external ears, ear-canal system and acoustic loads make it more informative for many hearing-device tests than a microphone placed alone in free space. The manufacturer's description specifies representative adult dimensions and ear-simulation properties. https://www.grasacoustics.com/industries/audiology/kemar[GRAS: KEMAR construction and ear simulation]{ref}
An original manikin paper by <M. D. Burkhard> and <R. M. Sachs> appeared in 1975. Later studies used KEMAR to investigate device coupling as well as the surrounding sound field.<Anthropometric manikin for acoustic research by M. D. Burkhard and R. M. Sachs>[JASA 58 (1975), 214–222.]{ref}
For example, <Abhijit Kulkarni> and <H. Steven Colburn> repeatedly placed headphone cushions on a KEMAR and measured the resulting <headphone transfer function>. Repositioning changed the response, complicating compensation by a single fixed inverse filter. The experiment demonstrates that the ear–device interface is part of the acoustic system, rather than an incidental mounting detail.<Variability in the characterization of the headphone transfer-function by Abhijit Kulkarni and H. Steven Colburn>[Abstract and introduction: repeated supra-aural placement on KEMAR and response variation.]{ref}
An invented measurement comparison makes the meaning concrete. If the same electrical drive produces pressures of 0.020 and 0.010 pascal at one measurement frequency in two fittings, their <sound pressure levels> differ by $20\log_{10}2\approx6.02$ decibels. This is a fit-dependent response difference at a specified point, not an automatic judgment of perceived loudness or device quality.
A standardized manikin supports reproducible comparisons but does not reproduce every listener's ear geometry, physiology or perception. Conclusions should specify the simulator configuration and measurement conditions.
Back to article page
