Image Credit: Anton Ponomarev
Get to know the basics of sidechain compression in music producing with our quick intro.
As you get started producing you’ll soon begin to notice that instruments in your mix that have similar frequencies can interfere with each other, losing definition in sound. One tool available to deal with this is sidechain compression. But what exactly is it?
You can use sidechain compression to bring in sharper rhythm and more separation, making room for instruments in a dense mix. Normal compressors work independently, monitoring the level of a channel and controlling the volume of that same channel. Sidechain compression instead makes sure that a particular instrument is compressed relative to other instruments in a mix.
You can hear sidechain compression applied to the heavy bass frequency at 00:45 of Daft Punk’s “One More Time” as a kick drum enters the chat:
EDM producers refer to that pumping sound as “sidechain”. It’s the same basic idea as standard compression, but sidechaining triggers the compressor when a different signal gets louder – so the compressor affects one sound, but triggered by another.
It’s used when one sound in a mix needs to get quieter whilst another gets louder, much like “ducking” when music on the radio automatically reduces as the DJ begins to talk. In “One More Time” the kick drum dictates when the compressor clamps down, and the bass therefore gets compressed when the kick drum hits.
When a kick and bass play similar patterns, sidechaining makes sure the kick creates the attack, and the bass produces the sustain. It can also be used for example to make more room for a vocal in a dense mix.
Your DAW should come with a stock compressor that has a sidechain, or you can download an additional plugin. It works in two ways – the first part triggers the compressor, and the second lowers the volume. It usually gives you the ability to use high frequency and low frequency filters, so you can key in certain frequencies – and make the sidechain more sensitive to those certain frequencies.
It’s a complicated subject and we’ve only covered the basics, but sidechaining is a very useful tool to be aware of. Once you’ve gained an understanding of the purpose of sidechain compression, there are plenty of tutorials around to show you the numerous ways it can be applied.