Aux Send vs Bus

Two ways of getting signal out of a channel, often confused. An aux send taps a copy of the channel to a separate output — pre-fader, where the level is independent of the main fader, for monitors; or post-fader, where the level follows the fader, for effects. A bus, by contrast, sums several channels to a subgroup or the main output. In short: the aux is a per-channel tap, the bus a summing destination.