Bus or Bus BUS: A common connection of many different signals. An output of a mixer or submixer. A channel that feeds a tape track, signal processor, or power amplifier. A console output channel. It can best be described as a means of outbound transport for the signal. A common conductor used to collect and distribute audio signals. Bus > auxes, sends and returns a bus (or less commonly used "bus").. is the term that describes any kind of audio conduit that allows a selection of different signals to be routed/processed together. You feed the desired signals to the bus, apply processing to the resulting mixed signal (if you want), and then feed the signal on to your choice of destination.