What does the "gain" do on an audio amplifier?

Answer by  LPlatter (271)

I use gain as another volume control knob. It actually controls the volume of the sounds coming into the amplifier.

Answer by  GilFinn (2065)

Generally, "gain" is a voltage adjustment. In an audio amplifier, "gain" is used to adjust the sensitivity of the amplifier. Depending upon the source of audio input, gain is turned up or down to adjust for distortion. Distortion is caused by recording levels used for tapes, LP, CD's, etc.