Even after you’ve compressed all of the individual mics and/or components of your drum bus (see my drum compression chart), your drum bus itself can benefit from some light (or even some extreme) compression. Use this drum bus compression cheat sheet to bring a bit more cohesion to your entire kit.
Drum Bus Compression
My favorite type of compression to use on the drum bus is glue compression.
A VCA compressor like the Waves SSL G-Master Buss Compressor has a special knack on mix busses whether it’s on a sub/instrument bus or the main mix/master bus itself for tying multiple tracks together.
As the name suggests, it’s a light kind of compression which glues things together, and it works beautifully on drums.
Let’s cover the specifics in where to set each parameter specifically in this drum bus compression cheat sheet.
Threshold
Ultimately you might want to set the threshold on your drum bus compressor after the rest of the settings. This is because we ultimately want to achieve a very light bit of gain reduction overall, maybe 1-2dB on average, and we won’t know where the threshold for that will be to achieve it unless we have the rest of our parameters adjusted accordingly. Speaking of which…
Ratio
The ratio determines to what degree any level which exceeds the threshold is compressed by. We’re not trying to tame peaks so much here as we’re trying to pull everything together to help the entire kit gel together on that bus better.
As such, 2:1 which is the lightest setting on most glue compressors is a perfect ratio to just kind of nudge the drums together a little closer. If you want a bit more energy out of your drums, bump it up to 4:1 at the expense of a bit of the dynamics.
Attack
The attack on the drum bus compressor determines how quickly that audio which exceeds the threshold gets compressed and ultimately pulled down slightly.
3ms is a nice compromise to still get the benefit of the compression, but if you really want to preserve the punch of your snare, kick, etc. then bump this up to 10ms.
This helps to keep those transients fully asserting themselves in the mix before they get brought down via the compression.
Release
The release time on a drum bus compressor determines how quickly the compression turns off after the level drops back below the threshold.
Most glue compressors have an automatic release time which generally works well for audio with complex dynamics like you’ll find virtually any bus.
Gain
Manually add back in the gain which you lose via the compression with this dial to ensure the level sounds the same with or without compression.
This ensures that you’re not just adjusting the rest of the parameters for more or less compression and going with whichever sounds louder.
Doing this manually keeps the split test earnest so you can let the audio itself guide you rather than going by the level of the drum bus with or without the compression.
Parallel Drum Bus Compression
Parallel compression refers to absolutely smashing your audio with an extreme or infinite ratio. The idea with parallel compression isn’t to get a natural sound, but to output virtually every sound on that track at the same level.
It doesn’t sound natural on its own, but blended in alongside the dry audio it can give your audio a lot more energy and a pleasing thickness.
The easiest way to work this into your drum bus is to simply put a new compressor on an Aux/Return track with these settings:
Essentially you want to compress the entire practical dynamic range of the audio with the threshold from the quietest muted hi-hat to letting loose on the entire kit, cymbals ringing out.
We don’t care about transients with parallel compression as we’ve still got the transient punch from the “dry” instance of our drums, so we can go with practically an instant attack.
The ratio is the main controller here; set this to the max to absolutely obliterate your drum bus.
The key is that this is on its own Aux/Return track, so we simply blend in the amount we want via the “Send” knob.
You want to turn it up until you can barely hear the difference with it off versus on, and for a more subtle “feel” rather than “hear” effect you may want to back it off 1-2dB at that point.
You’ll find that your drums all of a sudden have this subtle be pleasant thickness added in. You can also use this same dedicated “Parallel Compression” track as a send for any tracks in your mix in need of a little added energy and thickness.
Once again, work a little glue compression on the drum bus itself to bring a little more cohesion to your drum bus, and blend in just a taste of that crushed kit via parallel compression on the side underneath that dry kit.
Combine these two forms of drum bus compression together and you’ll be loving how much fuller and better your drums are sounding, particularly in the context of the entire mix.
Don’t forget to also check out my complete overview on drum bus EQ to ensure you’re compressing only the best frequencies on your drum bus.
