Attack and Release are some
functions of a compressor.
The first thing you have to understand is the basic nature of sound. Everything has an attack (time it takes to reach peak), sustain (time it takes to hold that sound or note), and a decay (time it takes to reach absolute silence).
All a compressor does is change the variations between high and low volumes and brings them closer together. To make it simpler, it mashes a wave to allow it to seem "louder" or more even. This gives you more control of your sounds.
Compressors can function as
limiters,
De-essers and
gates as well. They are all variations of the same thing.
A typical compressor will have attack, release, ratio, threshhold and output gain features.
If you can understand the instrument you're applying compression to, then this will work better for you.
Threshold is the level at which the compressor will start working.
Attack is how fast you want the compressor to kick in
Release is how fast you want the compressor to close up or "let go" of the signal once it's being processed.
Ratio is the how much compression you want applied. This is done in fractions of your db input and output. Remember that anything above an 8:1 ratio is considered
limiting.
In other words, if you have a 1:1 ratio, you're basically doing nothing to the sound, because for every 1db going in, you have 1 comming out.
That's a crash course in compression.
