| 摘要 |
PURPOSE:To reduce the number of development loops of trial manufacture, evaluation and trial manufacture to a large extent, by generating sound based on desired sound pressure and frequency characteristics of an input from an input device before the trial manufacture of a speaker, and repeating the evaluation of sound quality. CONSTITUTION:A terminal device 7 is operated by an input device 6, and desired sound pressure and frequency characteristics are inputted. Hilbert's conversion and reverse Fourier transformation of the data are carried out and impulse response is obtained. Then, impulse response data for a sound generating speaker 14, which is recorded in an external memory device 11, is read out. Convolution integral of the reverse characteristics and the impulse response corresponding to the sound pressure and frequency characteristics is carried out. A tap coefficient is obtained and written into a ROM12. The ROM12 is set for a digital filter 13. Then a music signal is outputted from a music source 1 and inputted to the sound generating speaker 14 through the digital filter 13 and an amplifier 3. Thus the music having the desired sound pressure and frequency characteristics, which are inputted from the input device 6 can be obtained. |
