Stereo Bus
Definition
The final two-channel summing point in a mix where all tracks and buses combine before reaching the monitoring system or being bounced to a stereo file. Synonymous with master bus and mix bus in most digital workflows.
In Simple Terms
The final two-channel output of your mix — where everything combines into the left/right file that becomes your master. Same as the master bus in most setups.
In Practice
A stereo bus compressor and mastering-grade EQ are inserted on the stereo bus to apply subtle glue and tonal shaping to the entire mix as a unified whole before delivery.