Input Gain
Input gain is the amount of amplification applied to an incoming audio signal before it is recorded, converted, or processed further. In practical use, it helps bring microphones, instruments, or line sources up to a usable level, but too much input gain can cause clipping at the input stage.
Quick facts line:
Also called: preamp gain, mic gain, input level control
Used for: microphones, instruments, line inputs, audio interfaces, mixers
Main job: raise incoming signal to a workable level
Main risk: clipping the input if set too high.
Example:
You plug a microphone into an audio interface and turn the input gain knob until the signal reads healthy without going into the red. Focusrite’s guidance shows that green indicates a good level, amber means you are close to clipping, and red means the input has clipped and the gain should be reduced.
Gotchas:
- Input gain is not the same as output volume. It affects the strength of the signal entering the system, not just how loud you hear playback. This is an inference from how Focusrite describes preamp gain as the level going into your computer and DAW.
- More gain is not always better. If the incoming signal is pushed too high, the input can clip before recording, which creates distortion you usually cannot fix later.
- Input gain depends on the source. A quiet microphone may need much more gain than a hot line-level signal or a loud instrument. I cannot confirm one universal setting because the required gain varies by source and hardware. Focusrite’s auto-gain reference supports this by showing gain is set based on the signal received.
- Good input gain is part of gain staging. Focusrite’s auto-gain targets an average of -18 dBFS in the DAW, which is a practical reference point for leaving headroom while recording.
FAQs
Related terms:
Gain • Audio File • Audio Export • Background Noise • Equalization (EQ) • DAW • Frequency