| 摘要 |
<p>PURPOSE:To obtain a listening atmosphere wherein sound quality and a sound field are both optimum in terms of hearing sense by correcting not only an amplitude characteristic, but also a phase characteristic into ideal sound field transmission characteristics. CONSTITUTION:An analog signal from an input terminal 1 is supplied to an A/D converter 3 through an anti-aliasing filter 2 and converted into a digital signal. This digital signal is divided into two through digital LPF4 and HPF6. Then, the output of the LPF4 is passed through an FIR type digital filter 5 to correct its phase characteristic. The output of the HPF6, on the other hand, is passed through an IIR type digital filter 7 to correct its amplitude characteristic. Outputs of both filters 5 and 7 are added together by a digital adder 8. Thus, the characteristics are corrected into ideal sound field transmission characteristics, so a listening atmosphere wherein sound quality and a sound field are both optimum in terms of hearing sense is obtained.</p> |
