What is the function of a mixer's gain control?

The function of a mixer's gain control is to set the level of input signals before processing. This is crucial in the audio mixing process because it allows the operator to optimize the signal strength of each input source, ensuring that the audio is neither too weak (which can lead to noise and a poor quality signal) nor too strong (which can cause distortion or clipping).

By adjusting the gain control, a user can enhance the clarity of the audio and ensure a balanced mix when combining different sound sources, such as microphones and instruments. Properly setting the gain ensures that the signals are adequately processed by subsequent mixing stages, like equalization and effects. Thus, effective management of the gain stage is a fundamental part of achieving high-quality audio output in various applications, whether for live events or recorded media.