What Everyone Should Know About Compression - # 8 of 100
The music production subject I’m asked most about is compression.
So here’s my number one piece of advice. Stop using it.
Well at least stop compressing absolutely everything, it’s sucking the life out of your music.
Compression 101
Here’s Wikipedia on compression:
“In simple terms, a compressor is an automatic volume control. Using downward compression, loud sounds over a certain threshold are reduced in level while quiet sounds remain untreated. Upward compression involves making sounds below the threshold louder while the louder passages remain unchanged. Both reduce the dynamic range of an audio signal. This may be done for aesthetic reasons or to deal with technical limitations of audio equipment, which is seldom able to cope with the dynamic range the human ear can tolerate.”
So put even more simply:
- dynamic range refers to the difference between the loud and the soft bits
- compressors make the loud bits softer and the soft bits louder
- compressors reduce the dynamic range of whatever they are applied to
The secret no one tells you
Strictly speaking, if you mainly produce music in a computer (and at the time of writing most reading this will), you don’t need to use a compressor in most situations.
This is because the dynamic range of a VST plugin isn’t anywhere near as great as a vocalist or live instrument.
Plus you can control the volume of a programmed part in a myriad of other ways before you should reach for a compressor.
Dynamics = life
But doesn’t putting something through a compressor make it more powerful?
Well, for various complicated scientific reasons to do with the way the human ear perceives sound, it may appear to be louder, but whether it’s more powerful is debatable, especially if you’re compressing everything.
Dynamics give your music life. Differences in volume will make your music more subtle, expressive, and ultimately stand out. Isn’t that “more powerful”?
When to use compression
I’m not anti-compression persay. I’m just anti- “compressing everything at mixdown to within an inch of it’s life just because you think you should or because everyone else does”.
Compressors are a very necessary and useful tool in music production. But they are also the tool which is most overused and misunderstood.
But here’s some situations where you should consider getting your compressor out (or more likely loading it up).
- Live or analogue parts. If you’ve got a vocalist, live instrument or an analogue synths in a track, a compressor is often essential.
- Create contrast between compressed and uncompressed parts. Heavily compress a part or parts to make them stand out from the rest of the track which isn’t.
- Sound design. A compressor can be a useful tool for sculpting a sound.
- Side-chain compression. Where you set the compressor to affect a part (like a pad), and another part (like a kick) determines when the compressor kicks in. This is how you get that (all too) popular “sucking” sound. It’s also often used to make vocals stand out without having to turn them up.
- Parallel compression. Where you send various parts to a compressor (usually at a high setting) and feed the resulting signal back into the mix. I often use this technique as you tend to get a much more “transparent” (ie you don’t notice it so much) result.
So before you reach for that compressor just think about it.
You might be using samples that are already compressed. The VST plugins you’re using may have compressors built in. When you master your track it will be compressed again. And if you get your music onto radio or in a club it will be compressed yet again.
So if you over-compress everything at mixdown stage too it’s going to sound awful.
Ok that’s my rant over. Just promise me you’ll stop it.
100 Things, Music Production | tagged compression, compressor, sound engineering, vst compressor, vst plugins
Reader Comments (8)
Good read.
Great info! Thanks for the post and perspective. I promise I'll stop using it so frequently. ;) LOL.
Woohoo! My work is done. :)
Well put, I think that most new artists are obsessed with compression because it's become one of those buzzwords that's thrown around in all the publications and blogs. Personally, I only use compression when I need to sidechain something. And even then it's only for pulling the volume down of the part in question, never to really act as a "compressor".
My rule of thumb is exactly what you said: change the sound as close to the source as possible. Instead of putting on a compressor at the end of the effects chain, go back and tweak the synth/VST/algorithm/sound/recording/inputs first to try and get what you need. If your bass drone is being overshadowed by it's own attack effect on the filter envelope, tweak the filter's attack and the amp's sustain! Don't just throw a compressor on and drive it to the max to get it "loud"!
Adding a compressor in most cases early in the mixing process is downright lazy. Adding it at the end? You're likely just destroying the dynamics of your track in an effort to make it "louder".
I think that's one of the biggest issues with music right now... everyone's focus on "loud". "Oi, mate, make this part louder." Actually, no, don't make that part louder, make the other parts quieter, especially if the part that needs to be louder is already hitting 0.0 dB.
Michael, you describe my point (even) more clearly than I do. I'm glad I'm not alone. Here's to expressiveness and subtlety.
Oh and by the way (and in the interest of full disclosure), I can't bear to listen to much of my back catalogue because I overused compression. I didn't know what I was doing and just thought it's "what you did". So I've not been immune to the ubiquitous compression hype. But I guess that's why I now feel so strongly about it.
And don't get me started about loudness! In dance music particularly, there's an obsession with "loudness" which me (and my ears) find extremely tiresome. Maybe I'm just getting old...
It's a fine line between getting older and growing wiser, innit? ;)
Ahem. Yes indeed it is... :)