| 摘要 |
PURPOSE:To expand the frequency band of reproduced voice so as to make it more pleasant to listen by generating high frequency components without amplifying noise components. CONSTITUTION:A band-pass filter(BPF) 1 extracts the signal components 101 of a central frequency f1 from input signals (original signals) 100. A double multiplier 2 multiplies the signal components 101 double and generates signal components (higher frequency components) 102 whose central frequency 2f1 of the band is one octave higher. An adder 3 adds the signal components (higher frequency components) 102 to the input signals 100. Thus, output signals 103 become signals with a wider frequency band and become clearer voice. |
