Patent ID: 8150070

Claim:
A sound signal equalizer for adjusting gain in each of first to n th (where n is an integer of 2 or higher) frequency bands of an initial sound signal, the circuit comprising: first to n th extraction circuits that are provided in corresponding fashion to the first to n th frequency bands and that extract and output a corresponding frequency band component of the initial sound signal, first to n th gain adjustment circuits that are provided in corresponding fashion to the first to n th extraction circuits and that adjust the gain of an output signal of the corresponding extraction circuit and generate first to n th sound region adjustment signals a synthesizing circuit that can synthesize the first to n th sound region adjustment signals in the initial sound signal, a first filter as a one-sided band pass filter provided with prescribed characteristics selected from high-pass characteristics and low-pass characteristics, the sound signal equalizer including first to (n−1) th filters; and a k th filter that has a wider pass band than a (k−1) th (wherein k is an arbitrary integer that satisfies the expression 2≦k≦n−1) filter, and that is the one-sided band pass filter, wherein the first extraction circuit extracts the first frequency band component from the initial sound signal with the aid of the first filter; the k th extraction circuit generates a difference between the output signal of the k th filter and the output signal of the (k−1) th filter for the initial sound signal, and outputs the difference as the k th frequency band component in the initial sound signal, and the n th extraction circuit generates a difference between the initial sound signal and the output signal of the (n−1) th filter, and outputs the difference as the n th frequency band component in the initial sound signal.