[I updated this archive on 4/4/99 when I realized the *.wav files didn't
work correctly when played on a Wintel PC. They are now high-quality mpeg
MP3 files (320kbps dual stereo) that should capture all the cues of the wav files]

These files demonstrate the 3-D sound synthesizer described in
my master's thesis. I used a recording of a helicopter, about .25s long, and 
filtered it using the model in the thesis. The 'copter moves (in the
binaural presentations) from overhead to the right. It should appear
to be overhead initially, and should fade out as it moves off to the right.
In the binaural w/reverb, the helicopter should sound more externalized 
(e.g.,outside of the head by at least a foot or so). The filtering was done
on a Power Mac using Matlab, as well as some file conversion done using
SoundEdit 16.

The beauty of the synthesizer is that it is extremely simple. The
elevation effects are achived using a 32-tap FIR filter, and the azimuth
effects are achived using a 1pole/1zero IIR filter. On the ugly side,
it isn't nearly as nice sounding as a personalized HRTF, but it sure uses 
a lot fewer multiplies!

This archive contains four files:
monaural.mp3 - monaural presentation
binaural.mp3 - binaural presentation
binwrevb.mp3 - binaural presentation with reverberation

Let me know what you think!

Phil Brown
cpbrown@isr.umd.edu
http://www.isr.umd.edu/~cpbrown/