Spatialized Auditory Displays

We will investigate the feasibility of a signal processing system that controls the perceived location of a virtual sound source for listeners wearing headphones. Starting from an approximate head-related transfer function (HRTF) individualized HRTFs will be adaptively approximated for observers in a psychophysical task. Average HRTFs have proven inadequate for consistently placing sound sources in azimuth and elevation, especially near the frontal midline. Recently developed adaptive algorithms permit the tailoring of generic HRTFs to individuals within training periods of acceptable durations. These transfer functions will be modeled as binaural spatial filters and implemented in real time using DSP processors under the control of a PC. This system will be used for preliminary psychophysical testing. Future systems will incorporate dynamic head position to further enhance the realization of spatialized auditory displays.