Localization Uncertainty in Time-Amplitude Stereophonic Reproduction

Abstract

This paper studies the effects of inter-channel time and level differences in stereophonic reproduction on perceived localization uncertainty. Towards this end, a computational model of localization uncertainty is proposed first. The model calculates inter-aural time and level difference cues, and compares them to those associated to free-field point-like sources. The comparison is carried out using a particular distance functional that replicates the increased uncertainty observed experimentally with inconsistent inter-aural time and level difference cues. The model is validated by subjective listening tests, achieving a Pearson correlation of 0.95. The model is then used to predict localization uncertainty for stereophonic setups and a listener in central and off-central positions. Results show that intensity methods achieve a slightly lower localization uncertainty for a listener positioned exactly in the center of the sweet spot. As soon as the listener moves away from that position, the situation reverses, with timeintensity methods achieving a lower localization uncertainty.