The Beginner's Guide to Mix Bus Compression

Can we take a time out real quick, step back, and look at what it is that separates a good mix from a bad one?

At first glance, a good mix has a good amount of separation. You should have clarity between instruments. Your listener should be able to hear your guitar and your bass separately, without any concerns of masking hiding parts of one or the other. Each vocal track should be aligned and reinforced for clarity and consistency.

But with all of that separation and processing, everything still needs to sound like it all belongs together.

This means you have to mix with glue. You need your tracks to sit tightly against each other – where one instrument ends another begins. Your mixes need to sound full, but not squashed, and the best way to draw that line is through the use of Mix Bus compression.

What is Mix Bus Compression?

Mix bus compression is simply any type and amount of compression added to your mix bus (sometimes referred to as 2-track, master fader & output) on your signals way out of your DAW, just as the name implies. It doesn’t require any fancy plugins, although some do a better job at mix bus compression than others.

The reasons behind why this compression gets used ranges from avoiding clipping to adding some flavor, but the most common reason is that engineers use the compression as glue on the mix. Everything else is just an added benefit.

How Does Mix Bus Compression Affect My Mixes?

Think of your mix bus compression as part of your audio signature on each mix. Your compression, in combination with anything else on your mix bus, is your sonic imprint, letting the rest of the world know it’s your mix.

Ever listen to a song and immediately know who mixed it (or at least had a pretty good idea)? You might pick up on an engineer’s preferred snare tone or guitar sound, but more often than not what you’re hearing is the imprint left by the mix bus processing they use.

And while no mix bus chain/settings are going to fit every song, most engineers find themselves returning to a similar mix bus signal path time and time again because it sounds right to their ears.

Common Mix Bus Compressors 

As I mentioned before, not all compressors act the same way when it comes to your mix bus. Some of the stock options will work in a pinch, but they’re not usually designed with your entire mix bus in mind.

Mix busses are tough creatures to tackle, which is part of why mastering compressors are in a whole different price bracket than the ones you’ll commonly find in recording studios. Instead, you may notice a trend toward some common preferences among recording engineers:

The SSL-Style Comp

SSL is known for making great recording consoles that are easy to work with, but they’re less known for making extremely colorful recording equipment. While SSL preamps are clean and professional sounding, they’re often replaced by other options when an engineer is looking to add a bit of color.

The same could be said for SSL compressors. Their consoles (and the plugins modeled after them) all have very similar characteristics. Some engineers will drive them hard, but the majority of use you see with SSL compressors are hitting them just barely enough for the needle to move.

This light compression approach glues things together while sounding extremely transparent and works best when you have other parts of the signal chain you want to let shine through.


API is also a huge name in the hardware world – especially when it comes to consoles, preamps & compression. Think of API-style compressors as the hard-rocking alternative to the SSL. They can be pushed harder (resulting in more glue/compression) and tend to add an edgy coloration to your sound.

Users of API-style compressors need to be wary, because too much compression can lead to distortion and mud quickly. They can bring a lot of cohesion to your sound, but tend to have a single tonal quality that either works, or doesn’t.

The Combination/Alternative

Plugins have brought a lot of new and interesting compressors into the mix over the last several years to the point that many are competing with, and even beating, the several thousand dollar hardware alternatives (even the mastering ones). With such a low cost of entry, engineers are flocking to see what the hype is about.

While the early entries were all about “perfectly cloning” the hardware sound, the flexibility of digital are leading the way into completely new and uncharted territory.

Now, mix bus compressors like BG-Mix are providing multiple algorithms, which means multiple approaches and tonal characteristics. Engineers no longer have to settle for the carefulness of an SSL or the boldness of an API, they’re all available in one compressor.

Not only that, but the plugins are able to find the overlaps between those compressors for new, hybrid approaches. They’re capable of adding never-before-heard compression approaches, all of which can be part of your sound.

I’m excited to see where the technology continues to grow, and how it might impact the way engineers are using mix bus compression. Now, more than ever, engineers can find the sound that is uniquely theirs when all of the options are placed at their fingertips.

What Kind of Tone Do You Go For?

Are you more of a transparent compression mixer or do you strive to add a bit of grit to your mix bus?

Let us know which side you’re on and why over on the Joey Sturgis Tones Forum. There, you’ll find thousands of engineers and producers working to collaborate and improve their craft.

Happy Mixing!