The goal of this project is to simulate an out-of-head experience of sound motion over headphones. Our approach is to reconstruct the information intrinsic to the sound pressure wavefront of a moving object as it travels along an arbitrary trajectory in three-dimensional space. Various cues to motion such as Doppler shifts, changes in interaural-time delays, changes in interaural-intensity differences, and sound scattering by the head and pinnae can be shown to have dependencies obeying the physical laws of kinematics. We apply these lawful relations to develop mathematical techniques for synthesizing stimuli to be played over headphones. The precise stimulus control afforded by this approach will allow future psychophysical tests to determine which features of the acoustic wavefront human listeners use to track sound trajectory.
Jenison, R. L., and Lutfi, R. A. (1992). Kinematic synthesis of auditory motion. Journal of the Acoustical Society of America, 92, 2458. * Wang, W., and Lutfi, R. A. (1994). Thresholds for detection of a change in the displacement, velocity, and acceleration of a synthesized sound-emitting source. Journal of the Acoustical Society of America, 95, 2897. * Stellmack, M.A., and Lutfi, R. A. (1994). Observer weighting of concurrent binaural information. Journal of the Acoustical Society of America, 95 2916.