Sidechain Compression: The End All Be All Guide
“What I dream of is an art of balance.”
— Henri Matisse
Sidechain compression is undeniably an effective production technique, especially when creating balance in electronic music. While teaching hundreds of producers, I've learned that sidechain compression — in its many forms — can elevate an average production to a great one.
Sidechain compression has not one, but two main purposes:
- To create that pumping effect we all know and love...
- To create room and space for elements in your track...
That first one is the easy one, it's that classic pumping effect in Eric Prydz's 'Call On Me' or the iconic down lifters in Deadmau5's 'Strobe' that add so much movement and emotion even when the kick drum is not playing.
But the second purpose, creating room and space and making your tracks live and breathe and react to the very music itself....well, that's a completely different ball game.
I'm writing this article to create the best guide on the internet to sidechain compression. I will teach what sidechain compression is, how and why to use it, and give you some actionable pro tips to help you improve your sidechain game today.
What Is Sidechain Compression?
Sidechain compression is similar to regular compression but with one crucial difference. Whereas standard compression listens to the volume of a channel and reduces the volume of that same channel, sidechain compression reduces the volume of a channel by listening and responding to the volume of another channel, or the trigger channel.
In other words, regular compression reduces the volume on the main channel in response to the volume of the main channel, and sidechain compression reduces the volume on the main channel in response to another element in the mix.
But when it comes to the tools used for sidechain compression, you have two options. There is traditional sidechain and LFO sidechain.
Traditional sidechain is most similar to regular compression. Here, we actually use a compressor and just enable the sidechain feature. This is the workflow I demonstrated above, where we select the channel for a sidechain input and use the typical parameters within a compressor to control our gain reduction.
Traditional sidechain is most useful for subtle sidechaining effects that preserves a more organic, natural, and imperfect feel. Traditional sidechain compression is best for sidechaining the compressor unit to a trigger channel that is not perfectly in sync with the groove of your track (for example, a vocal). For this, we recommend FabFilter Pro-C, Waves RCompressor, or your stock DAW plugin!
LFO sidechain was pioneered by one of the music influential plugin creators for electronic music, Steve Duda (he also created Serum!). LFO sidechain doesn’t use a trigger channel to determine when to reduce the volume of the main channel — rather, you can design a shape and tempo within an LFO sidechain plugin that will repeatedly reduce your channel volume at a certain rate.
LFO sidechain is especially useful for sidechaining sounds to a kick drum in 4x4 dance music (like most EDM, house, and techno). Effectively, you can set your LFO sidechain to reduce your signal volume at the beginning of every beat of the track — this will get sounds out of the way of your kick drum. For this, we recommend LFO Tool, Nicky Romero Kickstart, and even Soundtoys Tremolator.
Why Use Sidechain Compression?
There are two main reasons to use sidechain compression – to create space in your mix and create a stylistic effect.
If you're looking to create space in your mix, sidechain compression will help reduce the volume of a channel in response to a separate trigger channel, it is an effective tool to get the two channels “out of the way” of each other. With sidechain in practice, when the trigger channel gets loud, the main channel gets quiet, and vice versa. This is great for balancing kick and bass levels and balancing a vocal and a synth.
If you're looking to create a “pumping” stylistic sound that characterizes so much of electronic music, sidechaining is the answer. Whether that’s the “on-off-on-off” pump characteristic of house and trance or the sudden dips in the volume of synth stacks in music from Flume, Madeon, and Porter Robinson.
I will dive into plenty of ways to implement both of these sidechain strategies in the Pro Tips section below.
How To Sidechain A Compressor
Technically speaking, sidechaining a compressor is pretty straightforward. You begin by adding the compressor to the channel whose volume you want to reduce, and then you select the trigger channel you want the compressor to respond to.
Whether you're a Logic Pro, Ableton, or FL Studio, we'll quickly break down how to set up simple input triggers with each of these DAW's stock plugins.
How To Sidechain In Logic Pro:
Logic's stock compressor is a powerful plugin with a fairly intensive GUI. While this may seem intimidating when you're first getting familiar with sidechain compression, setting up a simple input trigger to this powerful compressor is actually fairly straightforward.
It can be done in just a few quick steps...
Step One: Add the compressor to the channel you want to reduce in volume.
Step Two: From the “Side Chain” dropdown, select the trigger channel. This can be an audio track, a MIDI track, or a bus.
Step Three: That’s it! It really is that simple.
How To Sidechain In Ableton Live
Ableton Live is one of the most popular DAWs in the industry and offers a ton of different tools to help with dynamic control and mixdown improvements. For sidechaining, we recommend using the classic compressor plugin and not the glue compressor.
While the glue compressor brings a lot to the table, it does not allow for precise and minute adjustments in the attack and release settings which is paramount to many of the tricks outlined below.
Step One: Add the compressor to the channel you want to reduce in volume and click the down arrow to see the expanded menu options.
Step Two: Click the “Sidechain” button and select the trigger channel from the “Audio From” dropdown.
How To Sidechain In FL Studio
FL Studio's stock compressor offers a bit more control features than the previous DAWs. The noise gate features envelope controls that behave slightly different than the classic attack and release parameters typically seen on most compressors.
Nonetheless, setting up standard sidechain inputs is just as easy and straightforward as in any other DAW.
Step One: Add Fruity Limiter to the channel you want to reduce in volume.
Step Two: Click into the COMP section from the 'SIDECHAIN' dropdown to select your trigger. It's that easy!
Sidechaining Pro Tips
Almost everyone associates sidechain compression with creating that pumping effect typically seen in dance music, and while we certainly will cover how to achieve this, sidechaining can do so much more to your mixdowns once you know how to apply it correctly.
In this section, we will be breaking down high-level tips and tricks professional producers and mix engineers use in almost every mix to achieve movement, space, and power in each and every mixdown.
Pro Tip One – Sidechaining Your Bass To Your Kick
Sidechaining to your kick is the most common use of sidechains in electronic music. Both your kick and your bass occupy the low end of your mix — because they are both so huge, we don’t want them playing at the same time.
Sidechain compression thrives for exactly these situations and we can use either an LFO sidechain or a traditional sidechain to get your bass out of the way of your kick. I like using LFO style sidechains most of the time.
Step 1: Insert the LFO style sidechain plugin onto the channel with the bass. LFO sidechain doesn’t use a trigger channel to determine when to reduce the volume of the main channel — rather, you can design a shape and tempo within an LFO sidechain plugin that will repeatedly reduce your channel volume at a certain rate.
Step 2: Set the rate is set to ¼. LFO sidechain is especially useful for sidechaining sounds to a kick drum in 4x4 dance music (like most EDM, house, and techno).
Effectively, you can set your LFO sidechain to reduce your signal volume at the beginning of every beat of the track — this will get sounds out of the way of your kick drum.
Step 3: Set the shape so the volume is reduced at the beginning of the beat. This is why LFO Tool (the plugin pictured throughout this example) is the choice tool for the job.
It’s completely customizable and is our favorite option. It was the first plugin in this LFO-style and remains the most powerful LFO sidechain plugin on the market.
Pro Tip Two – Sidechaining Instruments To Make Room For The Vocal
Electronic music is often characterized by lush, full, massive-sounding synths. We love this about electronic music, but sometimes it can be difficult to squeeze in a vocal amidst this huge wall of sound.
The traditional sidechain can reduce the volume of your synths just enough to make a pocket for the vocal. The key is to use this subtly — we don’t want it to feel like the synths are dropping in volume, but rather that there is a little more space for the vocal to shine through.
Here’s how it’s done...
Step 1: Set up a bus that containing all the synths and instruments you want to sidechain. This may include synths, pads, FX, and anything else you believe may be clashing with your vocals in your track.
Step 2: Insert your compressor onto that new bus — here, we’re using traditional compression because the vocal isn’t perfectly snapped to the grid of the track. We want it to be a more dynamic, which means that FabFilter's Pro-C (pictured throughout the example) is the obvious choice of tools.
Step 3: Set the sidechain input to the vocal track.
Step 4: Use a low ratio (I like 2:1) and a medium to long attack and release on the compressor (start at 100ms for the attack and 300ms for the release, and tweak from there).
We do this to help the compression be more transparent since any obvious compression here will make the overall effect appear unnatural. The low ratios and long attack and release will help create space for the vocal without bringing too much attention to the fluctuating volume.
Step 5: If you are using a compressor like Pro-C, set the trigger to Ext in the Sidechain section.
This is where the Pro-C really shines, as dialing in on the parameters allows for better control and added detail that is simply second to none.
That being said, another option that creates similar results is the Waves RCompressor which offers a quick plug-and-play solution that is effective in most of these sidechain scenarios.
Step 6: Reduce the threshold until you start to see ~3db gain reduction when the vocal is playing. This tends to be the sweet spot of gain reduction, as it is just enough room for the vocal to pop through without making the compression on the instrument bus too obvious.
Pro Tip Three – Bandspliting with LFO Tool
LFOTool is an insanely powerful plugin. But sometimes, its effect on a sound can be overpowering. In order to get the benefits of sidechaining without having an overwhelming pumping feel in the track, I LOVE using the band-split feature.
Bandspliting allows you to only sidechain above or below a certain frequency. Imagine sidechaining your bass to your kick (like in Tip #1). With band-splitting, you can only sidechain the low frequencies and leave the higher frequencies untouched, which gives you the benefit of reducing the low end of the bass without creating an overwhelming “pumping feel”.
Step One: Insert LFO style sidechain plugin onto the channel with the bass.
Step 2: Now make sure the rate is set to ¼.
Step 3: Now, set the shape so the volume is reduced at the beginning of the beat.
Step 4: Then enable bandpass — set to Low Pass and set the frequency to 300Hz. Tweak the frequency from there.
Pro Tip Four – Input Monitoring with Traditional Sidechain
Sometimes when we sidechain, there are only certain parts of one sound during which we want to reduce another. For example, we might only want to sidechain a sound to the transient click of our kick and the occasional sibilance of a vocal.
How do we deal with these scenarios? We use input monitoring, which isn’t a feature of all compressors. We recommend using Fabfilter Pro-C as a third-party option, but luckily the stock compressors in Ableton and Logic allow for this as well.
What you do is listen to the signal you are sidechaining against. You can use an EQ to isolate the frequencies of the trigger channel you want your compressor to respond to. For example, in the input monitor, you use a high pass filter to isolate the high transient of the kick drum — now, your compressor will only respond to that frequency. Here’s how it’s done using Hpyerbits' favorite compressor, Fabfilter's Pro-C.
Step 1: Start by inserting your compressor for traditional sidechaining.
Step 2: Now set your sidechain input channel.
Step 3: In the Sidechain section, click Ext and Audition (now, you’ll hear the kick drum).
Step 4: Use a high pass filter to isolate the frequencies in the trigger channel you want to respond to (for example, the high-end “click” of the kick drum).
Step 5: Turn off Audition (it will save your changes). Now you can tweak the threshold to taste.
Pro Tip Five – Multiband sidechaining with Pro-MB
As we were inputting monitoring in the pro tip outlined above, we were tweaking the frequencies on the trigger channel in isolation. With Multiband Sidechaining, we tweak the frequencies on the signal we are actually sidechaining. This works very similarly to band splitting in LFOTool.
With multiband sidechaining, we select a frequency band where we want to perform the gain reduction. So, instead of reducing the volume of the entire signal, we are just reducing a certain band. This is especially useful for sidechaining a bass against a kick (like with band splitting in LFOTool). But, my favorite use of this technique is sidechain instruments against a vocal and only reducing the frequencies in the instruments that sit where the vocal is sitting.
We recommend using Fabfilter Pro-MB for this. There are other options, but Pro-MB provides the most control and flexibility.
Here’s how to do it...
Step 1: Insert Pro-MB on the channel you want to sidechain (in this case, the Synths bus).
Step 2: Set your sidechain input channel (in this example, we'll be using the vocal).
Step 3: Create your band in Pro-MB. I’m going to reduce from 500hz-2kHz, where most of the vocal is sitting.
Step 4: Click Expert and EXT (for external input) on the band.
Step 5: Set a medium attack and release, and drop the threshold until you get ~3db gain reduction. You can tweak it from there, but this is the advised starting point.
Pro Tip Six – Mid-Side Sidechaining With Pro-MB
We can apply the same intuition from multiband sidechaining to mid-side sidechaining. Rather than selecting a frequency band to sidechain, we select to sidechain either the mid or side frequencies.
This is especially useful when sidechaining a wide bass to a narrow kick. We can reduce the mid frequencies of the bass when the kick is hitting but can leave the wide frequencies untouched. And with Pro-MB, we can even combine multiband sidechaining and mid-side sidechaining for Mid-Side Multiband Sidechaining™!
Step 1: Insert Fabfilter's Pro-MB on the channel you want to sidechain (in this case, the Synths bus).
Step 2: Set your sidechain input channel (we'll once again be returning to the vocal in this example).
Step 3: Create your band in Pro-MB. Drag the band to cover the entire frequency spectrum.
Step 4: Click Expert and the EXT (for external input) on the band.
Step 5: This is where things start to get a bit trickier. Drag the Stereo Link slider all the way to the right. This sets it to only reduce the mid frequencies.
Step 6: Set a medium attack and release, and drop the threshold until you get ~3db gain reduction. As before, this is a general starting point that you can further tweak to your own needs.
Pro Tip Seven – Sidechain Reverbs And Delays To The Dry Signal
This last tip can be used to both create space and clarity in your mix or to create an effect. When you add reverb or delay to a sound, sidechain the reverb or delay back to the dry signal. This reduces the volume of the reverb/delay when the dry signal is playing and accentuates the reverb/delay when the dry signal stops.
There are two cases where we use this trick all the time. The first is on vocals for cool delays at the end of each vocal phrase. The second is on huge synths stacks to create a vacuum-like space at the end of a big chord stab.
Step 1: Send your dry signal out to a reverb or delay bus.
Step 2: Insert a compressor onto the send. Placement of your plugins here is incredibly important, so ensure that you are placing your compressor after the reverb or delay plugin to allow the pumping effect to be applied to the tail of the reverb.
Step 3: Set the sidechain input to the dry signal.
Step 4: Set to Ext, set a slower attack and release, and reduce the threshold until you get about 10db gain reduction. This is much more gain reduction than in the other tips. Why? Because we typically don’t want to hear this effect at all when the dry signal is playing.
Step 5: Tweak the compressor release time to adjust how quickly the reverb/delay jumps in after the dry signal ends.
My favorite use of this technique is in Sun & Moon by Above & Beyond. Listen to the sidechaining on those synth chords!
Final Thoughts on Sidechain Compression
Sidechain is a critical tool for electronic music producers. Remember, we can use it for two purposes: to create space in a mix, and for a creative effect. Before we wrap up, I’m dropping some resources below to help you continue to expand your knowledge on where sidechain fits in with your productions:
- Sidechain is critical in our guide on getting the perfect kick-bass relationship
- Want to learn more about compression? Start HERE.
- We talk all about sidechain compression in our courses Mix Master Flow and of course, the Hyperbits Masterclass.
Making professional music is damn hard, and knowing how to sidechain is only one of the many skills a professional procure must master. If you are wanting to start producing music that is as good, if not better, than the artists you look up to, the Hyperbits Masterclass is the perfect solution. Enroll instantly, and start leveling up your music today.
Now get out there and start sidechaining — it’s essential to making amazing professional-quality electronic music.