Recording Tips: Sidechaining and How to Use It

If you’ve read our Compressor Basics For Guitar article, then you probably at least have a basic idea of what compressors are and how they work. If you haven’t read that, I’d strongly suggest it before reading on.

Go ahead, I’ll wait…

Now that you’re a pro at compression, and you understand all of a their basic parameters, such as Threshold, Ratio, Attack, and Release, we can move on to more complex uses of compression.

Today, we’re going to talk about the mysterious ‘Sidechain’ compression. A lot of people have heard of it, many have no idea what it is, other than it sounds super cool and fancy. I heard the term years ago when I first got into recording and it took many years before I decided that it was time to figure out what it was.

So let’s talk about it…

Sidechain Compression is the process of using the audio signal of one track to control the compressor on another track.

In other words, you choose two tracks. ‘Track A’ and ‘Track B’. Any time ‘Track A’ crosses the compressor threshold, ‘Track B’ gets compressed. Generally, the purpose of this is to allow for ‘Track A’ to stand out in the mix when it’s present, without having to lower or automate the overall volume of ‘Track B’.

Some of the most common uses for this are to create more space for vocal tracks and to help the kick drum to punch through the mix.

Of course, these effects can generally be achieved through the use of volume automation, but sidechaining is a neat trick that can help accomplish it for you.

Okay, so now you know what Sidechainin Compression is. Let’s talk about how to actually use it.

(I won’t be going over in detail how to dial in your settings in this article, just how to quickly set up for side chaining. So, before trying this on your own, I would definitely recommend our 7 Steps for Dialing In A Compressor guide.)

For this short guide, I’ll show how you can set up a Sidechain to help the Kick Drum stand out in front of the Bass Guitar.

1. The first thing to do is send your Kick Track to a Bus. Set the send as a Pre-Fader and set the level to 0 dB. Setting the send as a Pre-Fader allows you to change the volume of your Kick later when you’re mixing, without messing with the amount of Sidechain Compression.

IMPORTANT: If you are using a DAW that automatically creates an auxillary track when you send to a Bus, make sure you set the output of a Bus to ‘no output’. If you don’t do this then you will hear a second track of Kick Drum audio, which you don’t want.

2. Next, you’ll need to add a compressor to the track that the Sidechain Compression will take effect (in this case it is the bass track).

Now, this goes without saying, but the compressor you add to the track obviously needs to have a sidechaining option. Not all compressors have this option! Most DAWS these days come with a free plugin that does this. I’m using the Logic Pro X basic Compressor.

3. Now you’ll be routing your Bass Guitar’s compressor to correctly Sidechain with the Kick Drum Bus. Locate the Sidechain input setting and set it to the Bus that you sent the Kick Drum’s Pre-Fader to.

Some plugins will have a ‘Key’ instead of a Sidechain option.

Now that the Sidechain is connected to the Kick’s Bus, the compressor will detect the signal from the Kick Drum to compress the Bass Guitar.

4. Now that everything is routed properly, you can compress the Bass Guitar each time the Kick Drum is hit. A good starting point is with a fast attack and big ratio, then go from there. I usually aim for around 3 dB of compression on the Bass, depending on how extreme you want the effect to be. At this point you should be noticing your Kick Drum standing out in the mix quite a bit more, rather than fighting the Bass Guitar for space in the low end.

Try it out in your next mix and see how you like it! Just remember, Sidechaining is not a one-size-fits-all strategy and definitely not a replacement for corrective EQ.

Hopefully, this guide has given you a bit of insight into the world of Sidechainin Compression. If you enjoyed this be sure to check out our other articles! We post many lessons, guides, and reviews daily!

This article was written by Zac Buras, our editor in Louisiana