My colleague Steve DeMott did an article on 2-Buss compression recently. He describes various practical compression techniques and approaches when applying compression to a full mix on the stereo bus.  In this video, I take some of his ideas and develop them using Logic's powerful and flexible built-in compressor plug-in. There is a lot more to this plug-in than initially meets the eye, especially when it comes to "glue" style bus processing. 

The Compressor's Dual Mono mode allows for independent detection and parameter values for left and right sides or mid and side channels. Independent detection is critical for sensitive 2-Bus processing where you don't want the summed signal triggering both sides equally. In addition, filtering the detection circuit further refines how and what is being triggered by the Compressor. 

For example, a high pass filter set somewhere in the 300 - 500 Hz range, where there is typically a lot of energy present from the bass drum and bass, reduces the Compressor from being triggered by these elements. The detection controls in Logic's Compressor also include a choice between Max (where the Compressor compresses both channels if either stereo channel exceeds or falls below the threshold) and Sum (the combined level of both channels must exceed the threshold before compression occurs.) This adds further control to the Compressor's response to the incoming signal. 

The ability to have Logic's Compressor act upon the Mid and Side channels independently offers a fantastic tool to open up the mix's width. The independent gain staging is the key here to get the levels of the two channels blended as you want. 

All in all, Logic's Compressor has an impressive array of useful 2-Bus processing functions that will enhance any mix.