Sound image localization apparatus, stereophonic sound image enhancement apparatus, and sound image control system

摘要

A stereophonic sound image enhancement apparatus subtracts a right input signal from a left input signal and amplifies the subtracted signal to produce a difference signal, and also subtracts a right crosstalk signal from a left low-frequency-range enhanced signal obtained by filtering the left input signal. Then, the difference signal is added to this subtracted signal, and the added signal is outputted as a left output signal. Also, the left crosstalk signal is subtracted from a right low-frequency-range enhanced signal obtained by filtering the right input signal, and the difference signal is subtracted from the subtracted signal to output the subtraction result as a right output signal. Furthermore, a sound image control apparatus applies a left-channel head related transfer function to a monophonic input signal to output the resultant signal as a left input signal "Lin", and also applies a right-channel head related transfer function to this monophonic input signal "Min" to output the resultant signal as a right input signal "Rin". The sound image control apparatus performs a crosstalk canceling process operation with respect to these left input signal "Lin" and right input signal "Rin", and further mixes the left input signal "Lin" and the right input signal "Rin" with signals having phases reverse to those of the left/right input signals. Finally, the signals processed by the crosstalk canceling process and the mixing process are mixed with each other.