Toward Reality Equivalence in Spatial Sound Diffusion

Abstract

�The diffusion of sound in space has always been a major topic interest to many composers working with music composed, produced, or performed using electronic means. Despite the rich possibilities inherent in current sound diffusion and spatialization systems, none of the current systems can fully mimic the spatial characteristics of natural sound systems. By examining the nature of our spatial hearing and the history of sound spatialization systems, this article attempts to map possible routes, taking us closer to full ‘‘reality equivalent’’ sound diffusion systems. Since the remote transmission of sound became possible in the late 19th century, ways have been sought to enable sound systems to deal not only with the frequency and amplitude elements that make up a sound event, but also with the spatiotemporal ones. This is, naturally, of the greatest importance when the sounds being transmitted are musical in nature. Prior to the current era, all musical events were fixed in and wholly part of the acoustic location in which they were being performed. With the breaking of that age-old bond came enormous challenges for the audio engineer in finding ways of restoring the bond correctly after such space/time transmissions. Perhaps more importantly, enormous opportunities opened for composers explore and exploit the relatively little-known territory of space in music.