Q: I keep reading and hearing engineers talk about the “2-bus.” Maybe it’s a stupid question, but what is a 2-bus?
A: In traditional engineer/producer jargon, the 2-bus (not 2-buss, that would be something different) is the main stereo or 2-channel output from a mixing console. The term is now applied to virtual mixers, summing boxes, and more.
Many engineers apply overall processing to the stereo mix on the 2-bus, such as EQ and compression. Some 2-channel/stereo compressors — such as the SSL G Series and the API 2500 — are so commonly used for this application that many engineers refer to them as “2-bus compressors.”