| 摘要 |
PURPOSE:To prevent hardware clip of an output and to improve the fidelity of amplification by setting a radio of an input voltage increment to an output voltage increment to 1:1 when the clip state of an amplifier stage output is not detected and setting the ratio to infinity :1 when the clip state is detected. CONSTITUTION:A clip detection circuit 42 detects the state that an output signal of a voltage amplifier 28 is clipped, a clip indicator LED 44 is driven to inform the clip state. When the output is going to be clipped even by a little, the ratio of the input voltage increment to the output voltage increment of a gain control amplifier circuit (VCA) 26 inserted in an amplifier path is takes as infinity :1 and the output voltage is not entirely increased till the setting is released. Since the said ratio is kept to 1:1 in the state of the preceding output, that is, in the state of a signal level not causing a clip, no gain control is implemented. Thus, the hardware clip of the output is prevented and the fidelity is improved. |
