KEMAR Dummy-Head Microphone

Who is KEMAR?

Bill Gardner and Keith Martin of MIT Media Lab measured a series of impulse responses from KEMAR, a dummy head equipped with microphones in its ears. The measurements consist of the left and right ear impulse responses from a Realistic Optimus Pro 7 loudspeaker mounted 1.4 meters from the KEMAR. Maximum length (ML) pseudo-random binary sequences were used to obtain the impulse responses at a sampling rate of 44.1 kHz. In total, 710 different positions were sampled at elevations from -40 degrees to +90 degrees, with various representative azumith values. The dataset is freely available for research at MIT Media Lab.

Keith, KEMAR and Bill

The dataset includes three subsets: left ear, right ear and compact. Each set contains stereo responses for various elevation and azumith values. Left and right ear of KEMAR was shaped slightly differently (normal and large red, respectively) to obtain two independent sets of measurements from a single head, rather than having symmetric impulse responses by having the exact same pinna for both ears. The last set, compact, contains a set of normalized responses with a reduced length, for faster processing, taken from the left ear.

Sample Plots

Here is a series of sample responses taken from the left ear dataset.

	This response is from the case with azumith of 40 degrees (clockwise from "front") and elevation of 10 degrees up. Right ear response is stronger as expected, and overall response seems lowpass as the elevation is fairly flat.
	This is the case with azumith of -80 degrees and elevation of 50 degrees. Left response is definitely stronger, and the responses have more middle-to-high component for high elevation.

Matlab Coding

KEMAR dataset came with a complete set of matlab scripts to read the impulse responses from the raw data files. We simply wrote a wrapper-function to retrieve the data, convolve the input with the impulse responses, and write the wave files for experiments.

Here is the script.

The script generates a wave file with sampling rate of 44.1kHz.

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