In audio processing and sound reinforcement, an insert is an access point built into the mixing console, allowing the audio engineer to add external line-level devices into the signal flow between the microphone preamplifier and the mix bus.
Common usages include gating, compressing, equalizing and for reverb effects that are specific to that channel or group.[1] Inserts can be used as an alternate way to route signals such as for multitrack recording output or line-level direct input.