For those interested purely in 3-D audio synthesis, we have included a data-reduced set of 128 point symmetrical HRTFs derived from the left ear KEMAR responses. These have also been equalized to compensate for the non-uniform response of the Optimus Pro 7 speaker. The 128 point responses may be found in the tar archive ``compact.tar.Z''. The data-reduced impulse responses are stored in directories by elevation as described above. Within each directory each filename has the format ``HEEeAAAa.dat'' where EE is the elevation angle of the source in degrees, and AAA is the azimuth angle of the source in degrees.
Each file contains a stereo pair of 128 point impulse responses corresponding to the left and right ear responses for the given source position. For instance, the file ``H0e090a.dat'' contains the left and right ear impulse responses for a source directly to the right of the listener. The left response was derived from the 512 point file ``L0e090a.dat'' and the right response was derived from the 512 point file ``L0e270a.dat''. The data is stored as 16-bit integers and the stereo samples are stored in (left, right) interleaved order. Each 128 point response was obtained by convolving the appropriate 512 point impulse responses with the minimum phase inverse filter for the Optimus Pro 7 speaker. The resulting impulse responses were then cropped by retaining 128 samples starting at sample index 26. The maximum sample value in the 128 point data is 30496 in the file ``H-30e048a.dat''.