Day 6 pt 2 — An Intro to Compression
Fuck it. After some time to vent a bit, I might as well do what I said I was going to do. Instead of doing research and stuff though, I’m just going to talk about I know, and in a later post, we’ll learn together.
I don’t know much about compression. The two pieces of advice for beginners that I’ve read if you want to learn is this,
- Good compression is subtle
- Use the same one until you understand it
- Mess up
Who ever is reading this and is thinking, “But what actually is compression”?
To compress something is to flatten, or squeeze it. So what could compression do to music, but more importantly a sound wave? It will take the volume of your loud sounds and lower them.
Since you are squeezing your sound wave, that means you aren’t only pressing down on it, you are pushing up on it too. So your lower sounds will be boosted.
Compressors come in all shapes, sizes, functionality, but the functions that I will talk about below are on a significant amount of compressors, it is the basics to compression, and you need to know a little of what they do if you are going to try it. Or you’ll just be spinning knobs and won’t really hear anything.
This is the compressor that I used in my Day 5 Track Breakdown post. I’m going to explain what each knob does, and call it a day. There is also some physics to compression, so I’m going to do the best I can to explain it to you in the simplest way I can.
Just a reminder, I’m only talking about functionality. I’m still a rookie when it comes to compression, so practically I don’t know when to use to and how. My goal with this post is to refresh myself with the functionality and help you understand what it’s meant to do.
That top left knob, is your threshold. In music, you might hear people talk about dB, or the decibel of your sound. If you have a sound that is 10dB, it is louder than a sound that is -10dB. Makes sense, right?
So the function of the threshold is to set a limit to your sound. If you have a sound that is 10dB, and you set your threshold to 7dB, you are basically saying, I want all of the sound that I have under 7dB to remain untouched, but I want to compress everything from 7 to 10.
When talking about ratio, I think that one word that is important to know and understand is attenuation. This is a physics term, so if anyone is scared off by physics, all this really means is a gradual loss of intensity.
Ratio, from a numbers standpoint, is exactly what you would think it would be. The knob in the picture is set to 5. So that means your ratio is 5:1. If you move it to 3, your ratio will be 3:1. Simple right?
So if you set your ratio to 5:1, when your signal goes 5dB over your threshold, it will actually only go 1db over the threshold.
Quick review before talking about make up. Seeing the numbers always helps me understand things a bit better.
Example: You have a signal that’s sound ranges from about -15dB to -5dB, but once the sound gets to about -10dB, it’s just clashing with the rest of your music. What do you do?
You set your threshold to -10dB. Once it hit’s -10dB, you then need to tell the compressor how much compression should take place. What do you do?
You set your ratio!
I would then play around with this until it sounds okay. Keep in mind though, 2:1 compression is less compression than 3:1.
Knee is pretty straightforward. If you look at the picture below, there is a sound, a threshold, and a ratio. What the knee is, is the transition from the part of the sound before the compression, and the part after.
A hard is is a very sharp knee angle and will make the compression happen a lot more sudden. A softer knee will make it smoother.
Attack & Release
I’m going to group these together because one is literally the opposite of the other. If you understand attack, then you understand release.
Right off the bat, the first thing you can notice about attack and release is that the units are time, not dB. So you know that these control how long things happen for instead of dealing how loud or soft something is.
The attack is how long it takes for something to become fully compressed after you passed your threshold.
The release, is the exact opposite. It is how long the sound takes go from the attenuated state, compressed, to how it was before it was compressed.
Release time tends to be a lot longer than attack time, as you can see from the knobs. The attack knob only goes up to 200ms on this compressor, while the release goes up to 5000ms.
So that’s it, that’s the basics! I intentionally didn’t talk about about the makeup because these four functions are the ones that you will find on pretty much every compressor, and makeup not so much.
Again, I hope you all great Tuesday!