If you’ve checked out my mixing template, you know that I’m a big fan of bussing in my mixes. As I mentioned in my overview of what is a bus on a mixer, there are a number of advantages to using bussing in your mix. This includes they can be used to create a hierarchy in your mix from a track level all the way up to an instrument and ultimately master bus level. It also allows you to process the collective sum of multiple tracks, which yields a different result than applying the same processing to multiple tracks individually. This includes compression, and when bus compression is properly applied to a bus, it can make that sum of tracks sound a lot better and more cohesive.
With all that in mind, let’s cover the best settings to use in bus compression.
Bus Compression
While there are a few predominant types of audio compressors, a Voltage Controlled Amplifier or VCA style compressor oftentimes works best for creating the cohesion that you want on your instrument or vocal buses.
Also known as glue compression, this type gets its name from its ability to “glue” multiple tracks together, making sense of multiple tracks which otherwise wouldn’t sound or work as well together, whether the tracks were recorded in the same environment or not.
I like the Waves SSL G Master Buss Compressor which is based on an analog SSL 4000 G console’s bus compressor (it even features an “Analog” setting to impart some warm low level distortion noise to give your audio more of that analog console feel if you like).
That said, many DAWs come with a stock (free) glue compressor (like my Ableton Live).
The thing to keep in mind whenever you’re applying ANY kind of processing to a bus, compression or otherwise, is to keep it conservative.
When you’re processing a bus, you’re affecting multiple tracks at once. Higher up like with an overall vocal or instrument bus, you may also be affecting multiple BUSSES.
The idea is that the higher the number of tracks you’re affecting via that bus, the more conservative you should be because even the smallest adjustments will have disproportionately far greater reach and results.
This is reflected in my recommended VCA/glue compressor bus compression settings:

The audio compressor settings you’ll find on a VCA, glue style compressor are consistent with most compressors, so let’s go through each one.
Threshold
The threshold determines when the compressor engages. In other words, the combined level of that bus needs to reach whichever point you set here on the threshold before any compression will take place.
For instance, setting the threshold at -10dB means that once the volume of the bus exceeds -10dB, the rest of the compression settings will be applied.
Rather than setting this first, I like to set the threshold last after I’ve set everything to ensure that I get the amount of gain reduction that I’m after. In keeping with the conservative approach, I’m looking for 1-2dB at most, particularly if I’m using this on my master bus (incidentally check out my master bus processing chain).
Ratio
The ratio on a VCA or glue compressor is like any other; it determines how aggressively the audio which exceeds the threshold is attenuated.
On a VCA compressor like the aforementioned Waves SSL G Master Buss Compressor, there are simply three preset positions/ratios: 2:1, 4:1, and 10:1.
Like I mentioned in my recent overview on the best compressor ratio, in the case of bus compression you typically want to go on the lighter side, or in this case 2:1.
This means that every 2dB which exceed the threshold will be reduced by 50%, or output as 1dB lower.
A lower ratio isn’t about taming peaks, it’s about slightly smoothing out the dynamics of your audio without removing them altogether.
This is exactly what we want on the bus level; keeping the natural dynamics of our audio intact to keep our listener engaged while still gently nudging the various tracks together.
Attack
The attack on a compressor, including a VCA compressor on a bus, determines how fast the compression engages AFTER the threshold is met.
If you want to keep more conservative, I recommend opting for 10ms, meaning it will allow the first 10ms of your audio’s peak to pass through untouched before the compression engages on whatever is left.
The front end transients are typically the loudest part of your audio, not to mention they help keep a track(s) present in the mix by drawing the listener’s ear to them before the compression pulls them back down.
You can go as high as 3ms, but I wouldn’t exceed that as again we’re talking about a lot of different types of instruments on that bus, each with their own unique transients with unique times, all which add punch to the mix.
You can get more aggressive with a faster attack on an individual track level, but I find 3ms works well on bus compression, or backing that up to 10ms if you feel that your mix is losing its punch.
Release
I typically like the automatic release setting when we’re talking bus compression. The reason is I find it’s better for reacting to the complex dynamics that you get when multiple tracks are firing off at once, like when you’re compressing your drum bus.
This is in contrast to something with very predictable transients, like a single snare or kick which follows a similar pattern every time it triggers.
Bus Compression Reviewed
- Bus compression is a great way to bring cohesion or a sense of unity between multiple tracks feeding into a single bus, whether that’s an instrument bus or your master bus.
- Remember that less is always more when you’re compressing multiple tracks at once by way of a bus.
- With that in mind, aim for 1-2dB in gain reduction at most, particularly when you’re compressing your master bus.
- A ratio of 2:1 works best for ensuring that you’re not over-compressing the peaks of your bus.
- An attack of 3ms works well to maintain transients while enjoying the benefits of the compression, though 10ms preserves more of the punch for that bus.
- An automatic release time on your compressor is typically better suited for the more complicated dynamics you get when you’re compressing a lot of different types of tracks simultaneously as is the case with bus compression.