Compression is possibly the most discussed aspect of mixing. If you feel that you aren’t yet comfortable with compression, then starting with a good, clear explanation will get you where you need to be. We can’t think of a better introduction to compression than this primer from FabFilter.

In this free video tutorial from FabFilter, Dan Worrall explains compression using a vocal. So often people demonstrate compression using drums. In our estimation, this is a mistake. Learning compression starting with the human voice is the right way to do it. Watch and enjoy. This is the intro to compression we should all have had!

The visual feedback available in FabFilter’s C2 is brilliant. The meters on the right of the UI offer peak and average levels for input versus output, side by side making the downward nature of the gain reduction clear to see. The gain reduction meter inbetween gives the conventional, instantaneous reading we are used to but the gain reduction history in the scrolling window overlaid with the input vs output amplitude traces give an insight into the role of the attack and release times, which couldn’t be easily visualised in the past. Lastly, the peak input level being displayed in green along the transfer curve when the Knee section of the UI is displayed really makes it clear where your signal is in relation to the threshold. It’s a UI done right!

In the free tutorial below Julian Rodgers uses the Solo or “Difference” button of Avid’s Pro Compressor to use his ear to fine-tune the attack and release times. A UI is helpful but ultimately you have to make these decisions using your ears, Using a helpful UI can help inform what your ears are telling you but the can never be a substitute for careful listening

The following tutorials all examine different aspects of dynamics processing, mostly using compression but the last example is about MIDI compression! These are all premium tutorials from our Tutorial Channel, which you can try for free for two weeks.

Different hardware compressors have different characteristics and respond differently. This compression character is what makes some classic hardware so coveted. While not specifically imitating any particular compressor, the Avid Pro Compressor has different detection modes, which produce markedly different results. Here’s an examination of what they do and how they sound.

If you google “ducking” you’ll invariably find demonstrations of external key side chain compression. Ducking isn’t quite the same thing, though for most purposes it sounds close enough to explain the substitution. Watch the video to find out what the difference is.

Attack and Release times are what gives compression its sound: Bite, pump, punch and breath. They are all words that describe the effect of attack and release settings. If you need some help understanding what they can do, try this premium tutorial…

This might sound like a silly idea, it kind of is. after all, if you don’t want to use tremolo just turn it off! However, there is a serious point here. Because the effect of attack and release are so often demonstrated using percussive sounds, their effect on slower sounds can be overlooked. A sound that is constantly varying in amplitude is the perfect signal to investigate what happens when you compress sounds which change gradually.

People talk about different styles of compression: FET, Optical, VCA etc. What do they mean and is an LA2a a tube compressor or not? It’s got tubes in it so why do people say it isn’t? here’s an explanation with examples of each using UAD plugins.

It’s absolutely OK to use multiple compressors, it’s very common for a mixer to use compression at a few stages through the signal chain, with each doing a little bit of the work. if these compressors are used with different combinations of signals at different summing points in the mix the results of each stage of compression will differ but it’s also common to find more than one compressor used on a single track. this is usually because each compressor is doing a different job. The most common example is that of a slow compressor being used in combination with a fast compressor. What difference does it make which order they are in?

So much of the conversation about compression is about exploiting the audible artefacts that compression introduces. However, if you look at the design goals of nearly every hardware compressor they were all designed to be as transparent as possible! If you want completely transparent compression and you are using MIDI you can get it by using the approach of compression and applying it to the MIDI data. No audio compression involved so no compression artefacts! See how to do this in Pro Tools in this tutorial.