Synthesizing spatially complex sound in virtual space: An accurate offline algorithm

The study of spatial processing in the auditory system usually requires complex experimental setups, using arrays of speakers or speakers mounted on moving arms. These devices, while allowing precision in the presentation of the spatial attributes of sound, are complex, expensive and limited. Alternative approaches rely on virtual space sound delivery. In this paper, we describe a virtual space algorithm that enables accurate reconstruction of eardrum waveforms for arbitrary sound sources moving along arbitrary trajectories in space. A physical validation of the synthesis algorithm is performed by comparing waveforms recorded during real motion with waveforms synthesized by the algorithm. As a demonstration of possible applications of the algorithm, virtual motion stimuli are used to reproduce psychophysical results in humans and for studying responses of barn owls to auditory motion stimuli.