Here, a Compressor plug‑in on the synth pad track is being triggered by audio sent from a kick drum track.
We talk you through the basics of side‑chaining in Studio One.
Last month, we took a look at the various compression plug‑ins that ship with Studio One. One feature that I glossed over was their ability to use an external key input. This allows the ‘side‑chain’ signal feeding the detector section of the compressor to be different from the audio signal the compressor is processing. The example you’ll probably find most familiar is using a kick drum to pull down the level of a big synth sound so that the sound of the kick comes powerfully through the mix. It can subtly emphasise the kick in the mix, or it can be pushed harder, making the track throb and pulse.
So, this month, we’re going to look at how we do that in the context of the Studio One plug‑ins. We’re going to use the example of the kick drum to see if we can rescue it from being lost in the mush. You can of course, use this to highlight or emphasise any instrument you want, or use it purely for the pumping effect it can bring to your music, but let’s keep things simple.
Setting Up The Side‑chain
There may be lots of tracks that are covering up the action of your kick drum, but we’re going to focus on a single track of synths and a kick drum so that we can get a handle on what’s going on. So, open a nice fresh song and, delving into the Studio One Loop Library, head over to Pads / Loops, grab the file called ‘154_Disco_Loop_Synth Pad 1_Cmaj.audioloop’ and drop it onto a new track.
Next, poke around in Loops / Drums / Kick and you should find a sample called ‘Kick 90908.wav’, which is exactly the sort of thing we need. Drag that into another track. Now, this is just a single hit, so we’re going to need to populate the track with copies that run for the length of the pad. Select the single clip and press D (for Duplicate) as many times as it takes to fill the track out with kicks.
From the Effects Browser, drag the PreSonus Compressor plug‑in onto the synth pad track. Above the compressor controls, next to the preset menu, is the Sidechain button. Click to enable it and then click the arrow to the right. This brings up a list of possible side‑chain sources. In a big project, you’d have a long list of every track’s output, but here we just have the kick drum track. We have a choice between Send and Output, which largely depends on how we want to use the side‑chain source. The Send option works like an effects send, routing the signal to the compressor while the kick track continues to operate as normal. This can be pre‑ or post‑fader, so that the effect can be carried through regardless of whether the kick fader is turned up or not. With the Output option, the destination of the kick track becomes the compressor, so you’ll no longer hear the kick at all. This can be useful when you’re triggering compression from a sound source that you don’t actually want to hear, such as a click track. It also doesn’t have to be a single source; you can take sounds from anywhere and use them together.
Side‑chaining is one of those ‘secret sauce’ things to use while mixing that can give your tracks a sense of space and dynamics.
Pump Up The Jam
With our routing established, we are ready to start tugging on that side‑chain. Set Studio One playing back around the synth pad loop, and we’ll play with some settings in the compressor.
Pull down on the threshold and you’ll see the orange compression indicator appear on each thud of the kick. Pull it down to about ‑30dB, and you’ll experience the pumping effect that’s very common in EDM, with the kick drum thumping clearly through the synth. But there’s more we can do here. You can make the effect more extreme by increasing the ratio for some serious throbbing. For a more subtle effect, push the threshold back up to around ‑20dB, and reduce the attack and release times. The slot for the kick is now a lot more surgical and less like a throb.
You may want to be able to hear the effect without the kick. If you mute the kick drum track, you’ll also remove it from the compressor side‑chain, so that’s no good. Instead, set the side‑chain source to pre‑fader. Now you can turn the kick down in the mixer, but it’ll still hit the compressor. The level of the kick also has an impact on the side‑chain. If you set it back to post‑fader and vary the volume, you’ll see that as you turn the kick fader up, the amount of compression increases. That’s because the threshold is set against the level of the incoming kick, not that of the synth pad. Again, setting the side‑chain to pre‑fader will keep the compression consistent regardless of how you mix the level of the kick.
Side‑chain Filtering
The Studio One Compressor has a filter that can be used to weed out unwanted frequencies from the side‑chain signal. Why would you do that? Well, we don’t always have a nice clean kick track to use as our sound source. You could, of course, create one using a software instrument, or isolate a kick drum sample and route it directly to the compressor so it’s doing the work and not being heard. You could even extract the groove from the drums you do want to hear in order to get the side‑chained kick drum exactly where you want it — but that sounds like a load of work to me! Instead, we’re going to use the side‑chain filter to remove everything other than the kick so that our compression works correctly.
The side‑chain filter in Compressor lets you specify a narrow band of frequencies to trigger the compression, and it can be used on an external side‑chain trigger, or on the internal trigger signal, for example to set up de‑essing.
Let’s try this out with the ‘fh_drm120_chugger_stp.audioloop’ file from the same Kick library. Drag it into another track, mute the original kick track, and select the send for this track as the side‑chain source. This loop contains a bunch of tambourine and sticks mixed in with the kick, so when you run it, you have a lot of compression being triggered that’s in the spaces between the kicks. To clean this up, enable the Sidechain Filter and pull the high cut down until it’s removed all the higher‑frequency percussion, just leaving the kick.
Even when you’re not using an external key input as the side‑chain source, you can still use the filter to modify the signal feeding the side‑chain. On a vocal, for example, you could filter out everything below 5kHz or so such that compression happens only when a high‑frequency transient happens. This turns the compressor into an effective de‑esser — a useful alternative application of the same process.
In The Mix
If you are using this effect in a proper scenario with lots of different tracks, you can very easily add the same side‑chain effect to some or all of them. In the console, simply drag the compressor onto other tracks that you want to manipulate. Studio One carries all the side‑chain routing across, and it’s all there set up for you.
We can see this in action by dragging in the ‘154_Disco_loop_Synth bass 3_Cmaj.audioloop’ from the Loops / Bass / Loop folder into another new track. Copy the compressor across, and it will instantly work. If you check the sends for the kick drum, you’ll see individual sends are set up for each compressor, letting you fine‑tune how much is being sent to each one.
It doesn’t have to be all about getting the kick drum to poke through. You can use the exact same process to jazz up the rhythm of a piano or guitar with a hi‑hat track.
Beyond The Kick
It doesn’t have to be all about getting the kick drum to poke through. You can use the exact same process to jazz up the rhythm of a piano or guitar with a hi‑hat track. And it doesn’t have to be a compressor; you can use the Gate plug‑in to give a very clean and complete drop‑off, or you could use the Multiband Dynamics compressor to focus on one particular frequency range of the track.
Side‑chaining is great for vocals. If there are a lot of instruments with similar frequency content, then the vocals can get a bit lost. Using the vocal as the side‑chain source will pull the guilty tracks down whenever the vocalist is singing. You could also apply this to spoken word over a soundtrack or demo’ing a product. This is usually known as ducking.
Our ducking delay setup. A Gate plug‑in has been inserted after Analog Delay on an FX Bus, with a vocal routed to its external side‑chain input. Now, when the vocalist is singing, the delays are gated out, but when the singing stops the gate opens again.
Ducking Delay
Another cool trick is to side‑chain a delay. When you add a delay effect to a vocal, the delay can start to drown out the original vocal by repeating on top of the performance. You can sort this out by dropping in a Gate plug‑in, setting it to ‘Ducker’ mode and side‑chaining the vocals back into it. Let’s do that.
From Loops / Vocal / Electronic, drag in ‘Dubstep Vox 05 150bpm C.audioloop’ and bring up your tempo. If you put a copy at bar 1 and bar 5, that leaves plenty of room for the delay. Drag the Analog Delay plug‑in into the Console to create an FX Bus. Add a send from the vocal to Analog Delay. Set the Analog Delay time to 1/2, and you’ll hear the first reflection coming back rudely over the end of the vocal. Drop a Gate plug‑in onto the FX Bus after Analog Delay. Turn Ducker mode on and Enable the side‑chain on the Gate, selecting the dubstep vocal as the source. Now, whenever the vocals are playing, the gate closes — the echoes ‘duck’ out of the way, so we don’t hear them until the vocal stops and the gate opens again. You can fiddle around with the attack and release settings to tidy it up a bit, but it’s brilliantly effective.
Side‑chaining is one of those ‘secret sauce’ things to use while mixing that can give your tracks a sense of space and dynamics. But we all need to throb a kick drum through a pad from time to time, and that’s a great place to start.