| 摘要 |
PURPOSE: To create the sound field which is close to a natural sound source by converting tone color and sound quality, by setting an arbitrary frequency band characteristic without distorting original sound, giving the spreading feeling of a sound image and adding a high frequency band component in a pseudo manner. CONSTITUTION: After a sound dividing and synthesizing part 3 divides the sound band of a stereo signal into plural bands and makes the bands into prescribed levels, the part 3 raises the levels of the frequency components of a low-frequency sound band and a high frequency band for an intermediate frequency band by synthesizing the signal of each divided band. A sound field conversion part 4 changes the fixed position of a sound image and imparts the spreading feeling of the sound image by inverting the phase of the signal of an opposite channel and adding this signal to the output of the sound dividing and synthesizing part 3 after the signal is attenuated to a prescribed level. Further, a high frequency band signal generation part 5 extracts 10 to 20kHz components, for instance, from the output of the sound field conversion part 4, generates 20 to 40kHz components by a harmonic sound generation circuit, and adds the components to the output of the sound field conversion part. Thus, the reproduction of frequency components of 20kHz or more, the spreading feeling, the stereoscropic effect and the presence of sound can be obtained. |
