What Is Sidechain and How To Use It? Abbey Road Recordist Matt Jones Explains

Do you ever find your mix sounds great on one part of your track, but overcrowded or muddy on another part once more textures come in? If so, you may want to try using sidechaining. Abbey Road Recordist Matt Jones, who began working at Abbey Road in 2012, explains what sidechaining is, when it's most useful to use and his tips on how to achieve the best results with it.
 

Sidechaining with Matt Jones

Sidechain is an effect that you have on one sound that is triggered by the level of another sound. The classic example is when you have a compressor on a bass track and you set it so it ducks the level of the bass whenever a kick drum hits. This is so the kick can poke through for that moment when they’re sharing a lot of the same frequency space. So, rather than EQing to remove some of those frequencies from the bass, it can be nice just to duck it a little bit. It’s also a great way to get a track pumping if you use it in a more extreme way.

Having synths or pads – elements of a track with more sustain – being quite heavily compressed, but dependent on other elements in a track, is an excellent way to add a movement and that swelling effect that’s sometimes appropriate.
 
 
I often find it’s cool to sidechain sounds from a source that doesn’t already exist in a song. I was mixing a track recently that I recorded for BBC Introducing with Olivia Nelson where all the low end comes from this Moog synth – and it’s a really hefty mono sound and it works perfectly in the track, but it needed some kind of interest and movement. So I tried sidechaining it from the kick, because it was easy, but it didn’t really give us the shape that we wanted.

So, by setting up a new audio track – I think I just took one instance of a kick hit – and then we can copy it and paste it around, with clip gain up and down for accents. Ultimately, we reversed it and had it slightly off the beat. You end up with this loop on an audio track that would sound utterly ridiculous if you ever actually listened to it in the track. But if you send that to the key input of your bass compressor, it’s really straightforward to adjust the swells and the movement in the bass. Plus, it’s a bit more interesting than just ducking a bit every time the kick-drum hits.

I think sidechain compression on reverbs is often quite fun. If you have a really long reverb that produces a pad-type sound, having those pumping a little bit can be fun sometimes. It creates an interesting texture.

Read the full article as part of Music Tech's Ask Abbey Road series here.