Parallel compression can give any track in your mix more presence and energy. It’s incredibly easy to set up with any stock compressor, as well. Let’s talk about what parallel compression is and how to use it to enhance drums, vocals, even your entire mix.
What is Parallel Compression
Parallel compression is the technique of creating a duplicate of a track in your mix, dropping a compressor on that duplicate, and setting an extreme threshold and ratio.
That duplicate becomes a fat blob of overly compressed sound full of energy and devoid of dynamics. That parallel compressed track is then mixed in alongside the original dry version of the track to taste.
This technique adds thickness, energy, and presence to any lacking track in your mix.
Also known as “New York Compression”, this style of compression was heavily used amongst and became associated with engineers in New York City in the 90’s.
How much you blend in of the parallel signal is entirely up to you. You can mix it lower to where it’s more felt than heard, or you can turn it up a bit more so that it’s more noticeable when removed.
How to Use Parallel Compression
There are a few ways to use parallel compression. First, you should decide how you want to integrate it into your mix.
As a Duplicate Insert
A common use of parallel compression is to duplicate the track you want the effect on then dropping a compressor last on the signal chain. You can remove all of the effects on the duplicated track before the compressor to just parallel compress the raw audio or conversely you can leave them on for a more perfect duplicate.
In some DAWs like my Ableton Live, you can create a separate instance of the audio to process differently but on the same track.
In Live, you simply drop an “Audio Effect Rack” on the track then right click and select “Create Chain” to effectively add a second instance of that audio on the same track. You can then drop a parallel compressor on one of the two chains and treat the chain volume as the fader to blend to taste.
As Wet/Dry Insert
Another method is to use the wet/dry knob(s) on the compressor to blend your compressed and dry signals together to taste.
This works best when the plugin has separate knobs for the wet and dry signal like the FabFilter Pro-C. This gives you full control over the mix between the two, leaving the dry signal untouched.
You can adjust the parallel compression settings as you like, then keep the dry signal knob at its normal volume, blending in a bit of the compressed signal with the wet knob as desired.
As an Aux Track
A nice way to use parallel compression (and the way I typically use it) is as an aux/return track in your DAW. This way you can just have one instance of your parallel compressor in your mix and blend in the desired amount as a send as you go from track to track.
Having one instance of parallel compression you can blend in as a send on each track saves time and processing power.
To do this, simply create an aux/return track and drop a compressor on it.
No matter your workflow for adding it, let’s talk about the parallel compression settings to use to get the effect you want.
Parallel Compression Settings
Now it’s time to adjust the extreme parallel compression settings, the ones which make it ideal for this technique. Namely I’m talking threshold, ratio, attack, and release.
First, set the threshold to below the quietest audio in your mix that you plan to use parallel compression with. The idea is to ensure that everything we want to hear gets included.
You can drop the threshold to the floor to ensure EVERYTHING gets included, but then you run the risk of likely catching some ambient room noise on some tracks that you don’t want compressed and mixed in.
Note that your threshold might vary depending on which method you used to introduce parallel compression in your mix (duplicate track, aux/return as send, etc.).
For instance, if you have some tracks you want to use parallel compression on which are significantly quieter than most of the tracks in your mix, you may want to create a separate aux/return track just for those or instead use the effect as an insert on duplicated instances of those tracks.
I say this because if you set the threshold significantly lower than necessary for some tracks in your mix in order to accommodate for quieter ones, you’ll likely pick up and boost some ambient, unwanted noise on those tracks. Even if you meticulously cut the silence around those tracks, you’ll still pick up some of that sound mid-performance.
Set the ratio as high as it will go so that anything over the threshold gets reduced to the same volume.
Remember that the whole point of parallel compression is that it sounds like an overly energetic and squashed mess. 99% of the time, you wouldn’t play a track compressed to this degree as a focal point in the mix.
But when you blend it in with the uncompressed audio, it gives that track/those tracks more presence.
Set the attack near as low as possible, meaning as fast as possible. With conventional compression we’d aim for somewhere in the 1-5ms which is a relatively fast attack but one which preserves the transients.
We’re not trying to preserve transients with parallel compression because they’re still intact with the “dry” instance of the track. In fact, the more dissimilar the parallel signal sounds, the better.
With a super fast attack, the compressor clamps down on the signal virtually instantly, giving us the most compression possible.
A release of 100ms generally works well for parallel compression.
We don’t want an especially fast release because we want to keep the signal relatively compressed.
That said, we don’t want to leave the clamp on to remove the life of the audio entirely.
We get more of a responsive effect with a fast/bordering average release time and 100ms fits the bill.
Lastly and just as important as every other parallel compression setting is the amount of volume you blend in.
Again, the amount you mix in can range from more of the feeling that something is there to being very noticeable when you split test with it on or off.
Generally you want to turn it up until you can hear it, then back off a dB or two.
You should notice the difference without that parallel signal mixed in, but not to the point that the combined level is really dropping off.
What to Use Parallel Compression On
You can use parallel compression to beef up any track in your mix which you feel is missing that intangible. A few good applications include:
If a vocal is feeling a bit weak even after you’ve compressed it (see my best compressor settings for vocals), try blending in some parallel compression.
The parallel instance of the audio emphasizes every single syllable, so it brings a little extra cohesion and energy even when faintly mixed in.
Parallel compression works well in an individual drum track to get more sustain out of a snare, a kick, or it can be applied to the entire kit to add more energy.
You can even solo the parallel compressed drum track as a whole to get an interesting and raucous aesthetic for a bridge or one off section of your mix.
I just mentioned applying parallel compression to your entire drum kit, but you can use it effectively on most buses in your mix.
This creates a thick, heavily glued together mixture of every track playing on the bus at once. It can beef up an entire instrument group when used effectively.
Getting as macro as possible, we can even blend in some parallel compression on our master bus itself. When the finished mix feels like it could use a little extra “oomph”, use the audio effect rack method to create a parallel instance of your entire mix, crush it with parallel compression, then blend in as you like.
As with any processing on the master bus, less is more, so blend conservatively.
Parallel Compression Tips
- Parallel compression involves heavily compressing a signal and blending it in alongside the dry instance of the track.
- Parallel compression can be used on an aux/return track or on a duplicated instance of a track.
- It involves a low threshold to catch all of the audio of a track and an extremely high ratio to basically flatten any and all audio on that track.
- It also involves a fast attack to immediately clamp down on the signal and a relatively fast/average release time.
- Blend in enough of the parallel compressed signal until you can hear it, then dial it back a dB or two for a good mix.
- Parallel compression works great on vocals, kick, snare, an entire drum kit, most buses, and even on your master fader (in moderation).