Applications or INITs using 3D sound don't slow down. It's equalized for headphones but for some applications, particularly sound editing, loudspeakers work too. Transfer functions are computed in the Motorola 56001 processor, not the Macintosh. They act like part of the Toolbox and can be called from any programming environment. Its arguments are channel, azimuth, elevation, and distance.
Shipping is additional.
Bo came to Boston in August, 91. We stayed up til very late talking about the old days of SigGraph, etc. His company, Focal Point sells a board with some of his software on it. The input to the board is 1 mono analog audio channel and x,y,and z position for the output. The output is 2 analog audio channels that effectively place the sound at the specified location for the headphone wearer.