Interaural Time Difference Discrimination as a Function of Frequency and Time Differences

Abstract

Interaural Time Difference (ITD) is the main sound source localization cues by the human auditory system in the horizontal plane, ITD discrimination was measured for Gaussian white noise of various frequency bands and ITD in order to explore the perceptual mechanism of ITD. Seven values of ITD are selected discretely and inhomogeneous in accordance with qualitative analysis of perceptual characteristics for ITD and the signal was divided into 12 sub-bands based on the division method of critical bands on low frequency. The experiment results demonstrated that: the thresholds of ITD are more significant with frequency, they are smaller at 500 Hz, a maximum value especially when it reaches about 1500 Hz; the thresholds increase as the reference values of ITD increase. ITD the JND value increases with the ITD has tended to increase, the JND value is small when the ITD value change is more severe, but the trend is more consistent, when ITD large changes gently. This work will provide basic dates for comprehensive exploring of perceptual characteristics of the human ear and theory support for audio efficient compression.