一种音频双通道增益平衡前置放大器的实现

Realization of Two-channel Gain Balanced Audio Pre-amplifier

介绍了一种具有自动音量增益匹配的双通道放大器。它一个通道的增益由另一通道的输入音量所决定,使两通道信号经放大后输出的强度基本一致,从而最大程度地消除音量失衡。测试表明,两个幅值相差20dB的语音信号经放大器调整后幅值相差1.51 dB,听觉上已无差别。本放大器的这种功能给立体声拾音、扩声带来了最大的方便,具有很好的应用价值。

In this paper a kind of two-channel amplifier with automatic volume matching is presented. In this amplifier, one channel＇s gain is determined by the other＇s input volume, so that the two channels＇ amplified output could be nearly the same, and the volume imbalance could be largely eliminated. Test showed that the two input signals＇ amplitude difference which are less than 20 dB could be reduced to less than 1.51 dB after amplification, and the difference could hardly be identified by listening. The function of this amplifier brings great convenience to stereo pickup and sound reinforcement, so it is very suitable for application.