Abstract: A band-dividing unit is operable to extract a low frequency component from an input signal in order to generate overtones based on the extracted low frequency component, and is further operable to divide the extracted low frequency component into signals that belongs to different frequency bands. Each of overtone-generating units is disposed for corresponding one of the different frequency bands, and is operable to generate overtones based on an output signal from corresponding one of band pass filters. An adder adds the generated overtones to the input signal that has passed through a delay. The resulting acoustic signal is sent to the outside through a high-pass filter. One overtone-generating unit designed for a higher frequency band among the different frequency bands is set to produce the same or fewer overtones than another overtone-generating unit suited for a lower frequency band thereamong does.

Abstract: An audio-signal-processing apparatus includes a band-decomposition unit utilizing a band-decomposition characteristic based on the harmonic-tone composition of musical instruments. A low interval limit generates the harmonic-tone to each band signal after decomposing the bass signal into a plurality of band signals. The audio-signal processing apparatus generates a harmonic-tone individually for each pure tone component, which includes complex tones and suppresses deterioration of the sound quality.

Abstract: A method for shifting a pitch of acoustic signals, which are expressed in terms of a series of digital signals, to an optional pitch, uses a compacting and/or expanding process on the time axis and cross-fades a fade-in acoustic signal, stored in a memory with a fade-out acoustic signal, also stored in memory. The compaction and/or expansion of the time axes minimizes phase differences between the fade-in and fade-out acoustic signals to minimize tremolo in the output signal. The reduction in phase difference employs fundamental tones of the two series of signals selected by low-pass filtering the acoustic signal. One embodiment performs two-step compensation with a rough compensation using blocks of the digital signals and a fine compensation using samples from blocks.

Abstract: A band-dividing unit is operable to extract a low frequency component from an input signal in order to generate overtones based on the extracted low frequency component, and is further operable to divide the extracted low frequency component into signals that belongs to different frequency bands. Each of overtone-generating units is disposed for corresponding one of the different frequency bands, and is operable to generate overtones based on an output signal from corresponding one of band pass filters. An adder adds the generated overtones to the input signal that has passed through a delay. The resulting acoustic signal is sent to the outside through a high-pass filter. One overtone-generating unit designed for a higher frequency band among the different frequency bands is set to produce the same or fewer overtones than another overtone-generating unit suited for a lower frequency band thereamong does.

Abstract: The band-decomposition unit with the band-decomposition characteristic based on the harmonic-tone composition of the musical instrument and the low interval limit generates the harmonic-tone to each band signal after decomposing the virtually producing bass signal into a plurality of band signals. It generates a harmonic-tone individually for each pure tone component that comprises complex tone and suppresses deterioration of the sound quality. This makes it feasible to restrain increase in the number of band-decomposition units and to reduce the circuit sales.

Abstract: A method for shifting a pitch of acoustic signals, which are expressed in terms of a series of digital signals, to an optional pitch, uses a compacting and/or expanding process on the time axis and cross-fades a fade-in acoustic signal, stored in a memory with a fade-out acoustic signal, also stored in memory. The compaction and/or expansion of the time axes minimizes phase differences between the fade-in and fade-out acoustic signals to minimize tremolo in the output signal. The reduction in phase difference employs fundamental tones of the two series of signals selected by low-pass filtering the acoustic signal. One embodiment performs two-step compensation with a rough compensation using blocks of the digital signals and a fine compensation using samples from blocks.