| 摘要 |
PROBLEM TO BE SOLVED: To reduce the capacity of a coefficient table. SOLUTION: A filter arithmetic section 10 obtains sets of filter coefficients in response to an input parameter and they are fed to an evaluation section 14 and a selector switch 15 via a revision section 11. The evaluation section 14 evaluates whether or not desired sound quality is obtained (proper or improper) from the filter coefficients of the set obtained through an arithmetic operation based on the input parameters stored in each evaluation item memory 12 such as a level of a center frequency, a frequency sharpness, and a cut-off frequency. When the sound quality is proper, a selector switch 15 is controlled to be closed and a sound quality correction section 16 uses the set of the filter coefficients decided tentatively as they are to correct the sound quality. When improper, the coefficient revision section 11 adjusts the filter coefficients of the set obtained by the arithmetic operation so as to obtain desired sound quality and a sound quality correction section 16 corrects the sound quality by using the set of the adjusted filter coefficients. |
