Real Time Synthesis of Complex Acoustic Environments

This paper describes some recent efforts to "render" the complex acoustic field experienced by a listener within an environment. It represents an extension of earlier attempts to synthesize externalized, threedimensional sound cues over headphones using a very high-speed, signal processor, the Convolvotron (Wenzel, et al., 1988). The synthesis technique involves the digital generation of stimuli using HeadRelated Transfer Functions (HRTFs) measured in the ear canals of individual subjects for a large number of equidistant kcations in an anechoic chamber (Wightman & Kistler, 1989). The advantage of this technique is that it preserves the complex pattern of interaural differences over the entire spectrum of the stimulus, thus capturing the effects of filtering by the pinnae, head, shoulders, and torso.