Adaptive Amplitude and Delay Control for Stereophonic Reproduction that Is Robust against Listener Position Variations

With stereo reproduction, sound images are correctly located when the listener is located in a small area, called the sweet spot. When the listener is laterally away from this ideal location, the observed interaural level differences, interaural time differences, and interaural phase differences do not match the listener's assumptions because of unequal distances from the listener to the respective loudspeakers. In order to provide better localization beyond the sweet spot, the proposed system detects the listener's position to adaptively control the amplitude ratio and delay difference of the two loudspeakers. Results of subjective experiments using the proposed method demonstrate that sound images are localized more accurately than without such a system.