One mixing and production technique that will be present on the vast majority of records you own, especially those recorded in bigger studios with professional engineers, is that of buss compression. It can be hugely useful, both from an artistic and an engineering viewpoint - whether you want to go for that big, pumping, filtered disco sound, or just make sure your track is as fat as possible, buss compression can do wonders for your mix. But can anyone get involved? And how do you get started anyway? Let's look a little deeper....
The pumping disco-house sound, as pioneered by the likes of Daft Punk and their French cohorts, is all about buss compression. A classic example would be 'So Much Love To Give' by Thomas Bangalter and DJ Falcon. You can hear in this track how different everything sounds when the kick comes in. There is life in the the backing samples and loops when the kick drum is not playing - they have headroom and dynamic range. Then the kick thumps in, clobbering a compressor that sits across the whole buss, and the sheer volume of it forces everything else out of the way when the volume reduction kicks in.
To hear this technique really used to its full potential, listen to 'Barbara Streisand' by Duck Sauce. No matter what your opinions on the track itself, the buss compression is something to behold; it uses the compression and release technique outlined above, but also manages to achieve transients on the backbeat to give definition and a crisp top end. This is through a clever combination of a good buss compressor (perhaps the Waves SSL or UAD 4K for instance), and timing – adjust the attack of the compressor very slightly so that it allows some of the transient on your clap or snare through, and consider pulling the note early so that it has slightly more time before the compressor slams the door on it.
Buss compression isn't all about getting a massive house track pumping though. You can use it on any style of music as a central part of your mixdown. Many experienced engineers will put a compressor on their master buss before they even start mixing down. This may sound counter-intuitive, but it is common practise in many studios. It has many advantages - mixing through a compressor means you need much less compression at the channel stage, and thus can bring a mix together much more quickly. It's also often appropriate for dance and rock music in particular (anything with a strong groove and a lot of energy) - as it changes the way you approach a mix, focusing more on drums and bass, then fitting the other elements in around them. For very audible examples, check out some of the late 90's and early '00s techno releases by the likes of Ben Sims and Marco Carola; the intense percussion sounds bounce off each other as they jostle for space, constantly butting up against the threshold of the compressor. It creates an exciting and lively overall sound, less controlled than compressing everything individually.
It needs to be said here that this isn't something you can just try occasionally - it takes time and practise to get used to mixing through a compressor. To get you started, a general rule of thumb for compression settings would be a short attack (less than 10ms), medium-long release (maybe 200ms depending on the tempo of your track, longer if it's a slow track) and a threshold that takes off 3 or 4dB. Put the compressor on before you start mixing, and then don't take it off again!
Your first few mixdowns using this technique may not come off well, but practise makes perfect - it's a little like learning a new set of monitor speakers. Reference your mix often, take plenty of breaks, and persevere to be sure of really getting a handle on it!
Buss compression is a useful tool for all engineers, and you can get on board with it too - it just takes a little time and a good quality compressor. So get yourself a decent plugin, open up that mixdown, and see if you can't make those tracks jump out of the speakers even more!


