Glue Your Sound Together with Mix Bus Compression

When you look back at the last fifty years of sound recording, a timeline of trends, techniques, and equipment materializes. Tastes change over time, and while I’m not likely to ever use a gated reverb on snare drum today, you’d be hard pressed to find a rock album recorded in the 1980s without it. One technique that was virtually unheard of in the ’60s and ’70s that’s now considered by many as an industry-standard mixing practice is signal processing on your mix bus.

The advent of this practice has its roots in the 1980s, when the rise in popularity of SSL mixing consoles gave mix engineers a master bus compressor right in the board, which was not a common feature found in consoles before then. This compression has become what many refer to as the “glue” that holds your track together, and “SSL-style” compression denotes a very neutral sound that can range from subtle peak control to smashed tracks.

As times and tastes change, the signal chain on mix busses has as well. While purists may prefer to mix with nothing on their master bus, today it’s common to see engineers line up multiple compressors (one to catch the peaks, another for RMS or color), an EQ in the vein of Pultech, Manley, or George Massenburg, and for certain styles of electronic music, a brickwall limiter. Though far from a new practice, running your mix through colorful preamps, such as a pair of Neve 1073-style pres, can add depth and character, and is a popular “last step” for many mixers.

What makes mix bus processing so appealing is its ability to tie your mix together and add some character it might have been missing otherwise. You can add a touch of compression, some slight corrective EQ, or even dirty up your mix with some harmonic distortion. Plenty of tools exist both in the analog and digital domains, as there is no shortage of plug-ins from companies such as Waves and Slate that are designed to be home on the master track in your DAW.