What is an Aux Return?

An aux return, short for auxiliary return, is an input on a mixer or digital audio system used to bring an audio signal back into the mix after it has been sent out to an effects processor.

For example, a channel might send part of its signal to a reverb or delay effect using an aux send. After the effect processes the signal, the processed audio is routed back into the mixer through the aux return so it can be blended with the original sound.

Aux returns allow multiple channels to share the same effects processor while giving the engineer control over the level of the processed signal in the final mix. They are commonly used in recording studios, mixing consoles, and live sound systems.