Patent ID: 7672466

Claim:
An audio signal processing apparatus comprising: splitting means for splitting an audio signal of a first system and another audio signal of a second system into pluralities of frequency band components; level comparing means for calculating a level ratio or a level difference between each of the frequency bands of the first system and each of the frequency bands of the second systems; output control means for removing frequency band components whose level ratio or level difference calculated by the level comparing means is equal and substantially equal to a predetermined value from at least one of the first and second systems, and phase difference calculating means for calculating a phase difference between the frequency spectral components from the first system and the frequency spectral components from the second system, wherein the output control means controls the level of the frequency spectral components obtained from at least one of the first and second systems on the basis of the calculation result of the level comparing means and the phase difference calculated by the phase difference calculating means and removes the frequency spectral components whose phase difference is equal and substantially equal to a predetermined value from at least one of the frequency spectral components of the first system and frequency spectral components of second system.