| 摘要 |
PURPOSE:To realize an audio device of high S/N. CONSTITUTION:The audio device where an audio signal A is subjected to first sound volume adjustment in accordance with a first control signal E indicating the adjustment level of general first sound volume adjustment and is subjected to second sound volume adjustment thereafter in accordance with a second control signal F indicating the adjustment level of second sound volume adjustment for a derivative signal C derived from the audio signal like the output of an equalizer or a fader circuit which receives the audio signal is provided with a voltage/current conversion part 25a, a current ratio distributing part 25b which receives the output of this conversion part 25a, and a current/voltage conversion part which receives the output of this distributing part 25b to generate the output after the second sound volume adjustment, and the voltage/current conversion part 25a receives the derivative signal after the first sound volume adjustment, and its operation current is controlled in accordance with the first control signal, and the operation current of the current ratio distributing part 25b is controlled by the second control signal. |
