Interaural intensity and time differences in anechoic and reverberant rooms.

Abstract

The purpose of this investigation was to describe the physical characteristics of an artificial head and to determine the interaural time and intensity changes which occurred at selected azimuths. Measurements were conducted in a reflection free environment and in controlled reverberation conditions. The frequency response of the head microphones simulated the average response curves at the human auditory canal. In the anechoic chamber, the sound pressure at the ear nearest the speaker remained constant as the head moved from 0° azimuth to 45° and 90°. A reduction in intensity was observed in the far ear at azimuths of 45° and 90°. The decrease in sound pressure was observed in the middle and high frequencies. A “build-up” in the intensity level was found during the reverberant conditions. In the anechoic chamber, interaural time differences ranged from 0.42 to 0.56 msec at 45° azimuth and from 0.76 to 0.81 msec at 90° azimuth.