In the previous installment of Audio FX 101, I talked about what compression does to your tracks and how to properly apply it in different situations. In this continuation of what compression does, we'll talk about arguably the most popular compression technique used in dance music, Sidechain compression. Anybody that calls themselves a producer has used this technique in their tracks and it's become a prominent production technique in a variety of different genres, let alone dance music.
For those of you that may not be familiar with side chain compression, allow me to explain what it is and how it works in a finished song. Let's say you're listening to a house song with the typical "four on the floor" kick drum beat. If you really listen closely, you'll notice that the kick drum and bass are never hitting at the same time. There reason why they're not being used at the same time is due to phase cancellation.
Phase Cancellation is when two or more tracks of similar frequency ranges are working against each other. When the two different tracks are not aligned, the resulting sounds will be weak and lacking clarity in that frequency range. Now you may be wondering, "how does side chain compression help this matter?".
It's simple. When you add side chain compression to two different tracks with similar frequencies, it will create a "ducking" effect where one frequency will come in with the other following immediately after that signal. That's why you may hear a throbbing or ducking sound in the percussion section of your favorite dance tracks. You want to use side chain compression to create space for those different tracks while allowing them to share the same frequency range. In dance music, having a strong rhythm section is key to keeping everybody on the dance floor so proper use of sidechain compression is crucial .
Now for those of you that have just started out producing and are wondering how to use side chain compression on a track, let me explain one easy way you can side chain some of your tracks. While this example can be applied to most DAW's, I'll use Ableton as my DAW for this example.
Let's say you have a song sketched out in Ableton. You have the bass laid out and have a kick sample serving as your kick drum. When you play them together, you will probably come across some sort of phase cancellation that we discussed at the beginning of this article. Here's three steps to follow that will help solve that issue and give you a basic side chain compression.
Step 1: Add a compressor to your bass track
While most native compressors in Ableton will work for this process, I'm going to use the Glue Compressor for this example. Add the glue compressor to the bass track and click the yellow button that opens up the side chain option. Click the side chain button. When the side chain function is activated, the button will be yellow.
Step 2: Route your kick sample to come through the compressor
Once the side chain function is activated, go to "audio from" dropdown box below that button to route the kick sample into the compressor. Once that is routed, you can begin to dial in the compressor to fit your needs.
Step 3: Adjust the compressor functions to dial in best possible side chain effect
Once the kick sample has been routed into the bass compressor, you can now adjust the different knobs on the compressor. Ideally, you would start by dialing back the threshold knob to enable the initial pumping motion that can be seen in the compressor. Once you have found a good spot for the threshold, dial in the settings you desire for the attack, release and ratio knobs. Finally, there is a make up gain knob next to the threshold knob that can be used for repairing any lost gain. I wouldn't recommend using too much make up gain in this scenario as you don't want to lose clarity from your side chain effect.
Hopefully that example will help out many of you beginners out there trying to use proper side chain compression in your tracks. Keep in mind, this is a very basic example that is intended to walk you through the rudimentary aspects of the technique. Depending on the compressor you're using, you can dial in many different functions to help the technique really stand out.
There we have it! A nuts and bolts breakdown of what side chain compression is, how it affects your favorite dance tunes and a tip for some of you beginners looking to apply side chain compression into your tracks for the first time. I hope all of you have a better understanding of how this technique works and why it's so important to implement for all dance tracks!