Patent ID: 8000824

Claim:
An audio signal processing apparatus comprising: a high-pass filter for extracting from an audio signal a frequency component equal to or higher than a frequency f 0 ; n band-pass filters for extracting, from the audio signal, frequency components falling within a frequency range from the frequency f 0 /N to a frequency f 1 /N; n harmonic overtone generators for frequency multiplying each of outputs of the n band-pass filters by N to generate harmonic overtone components having multiplied-by-N frequencies; a first combining unit for combining the harmonic overtone components generated by the n harmonic overtone generators; a level detector for detecting a level of a combined harmonic overtone component supplied from the first combining unit; a gain controller for controlling dynamically the combined harmonic overtone component supplied from the first combining unit based on a detection output from the level detector; and a second combining unit for combining the frequency component extracted by the high-pass filter and a controlled harmonic overtone component output from the gain controller, where N is 2n (n being a natural number), the frequency f 0 is a first predetermined frequency, and the frequency f 1 is a second predetermined frequency higher than the frequency f 0 .