>Step by step
1. Sidechain bass and drum in action
1 So you have a new mix loaded up with your chords, a bass track and drum tracks. In its standard state, these elements of the track will probably sound OK, but you might notice the bass is masking the punch of your kick drum.
2 Get a compression plugin on your bass track’s channel strip. We’re using this on the bass track because that will be the affected instrument, ie the compressed signal, momentarily reduced in its dynamic range.
3 Select the sidechain dropdown in the top right of the compressor pane and select your kick as the instrument. This establishes where the input is coming from. This means the kick signal is going to the compressor on the bass track and the compressor will only act once that signal is received.
4 De-activate the compression plugin at first and play back the song. Listen to how it sounds with and without. When you then activate the compression, you should be able to hear a sort of pumping effect. This is the sidechain activated so that the full sound of the kick comes through.
5 To hear sidechain compression in its most extreme form, turn the Threshold dial on the compressor all the way up to -50 and turn your ‘ratio’ up too. This will exaggerate the effect so that you can see exactly how the bass is impacted.
6 It should sound kind of like there’s an attack on the bassline whenever the kick is triggered. In fact, there needs to be! Use Attack on your compressor and make sure it’s set fast rather than slow. As a starting point, take the attack all the way down to 0 ms. You can then start adjusting the compression components to your taste and needs.
7 Now change the Release dial. Similar to the attack, you also want a quick release time. The release is how long the compression stays active on the bass after it’s come into effect. We just want to give the kick room but not to mask the bass.
8 Bring the threshold back to about -25 and the ratio to about 3:1:1. While this is less extreme than before, because of the fast attack and short release window you’ll still noticeably hear the punch of the kick and dip of the bass.
9 The lower the threshold the more signal it takes for the sidechaining to activate. Find a good balance, bringing the threshold down, so that it isn’t too overpowering. I also recommend de-activating and activating the compression plugin as you’re working to hear what it sounds like with and without.
10 By using that A-B comparison, you’ll have a great gauge of how much sidechaining is best for the particular song you’re working on. Subtlety can be key – if you’re using sidechaining functionally you don’t want the effect to stand out, just to give the drums that bit of space.
11 Ratio will affect how much kick signal is coming through. You’ll probably find that about 3:1:1 is where you’d want to be at. Just keep on adjusting the threshold to your taste depending on how extreme you desire the effect to be.
12 Play your whole track through, using the A-B comparison to keep the changes you’ve made in focus. Hopefully, your kick is really coming through now but not to the detriment of the bass – just with a little ducking to make sure your low-end instruments are working harmoniously.