A compressor is an automated volume knob and it enables you to make a soft sound louder and a loud sound softer!
They process the dynamic range of the audio by varying the gain or the volume of that sound.
Dynamic range is the difference between the highest and lowest volumes of an audio.
Compressors can be used on everything. The variables are the input, threshold, ratio, attack, release, output level or makeup gain, and the VU meter.
The input level is the amount of input going into the compressor. When set at zero, the level leaving the computer is the same as the level going into the compressor.
The threshold is the user set level where any audio above the threshold is compressed and anything below the threshold is unaffected.
Next, is the ratio which is the ratio of decibels above the threshold to the decibels that will be heard after compression. So a 4:1 ratio means that for every 4 decibels above the threshold, 1 will be heard. If 16 decibels are above the threshold, 4 will be heard.
Limiting happens after a certain point (100:1 ratio), and you don't hear too much of a difference anymore.
Attack is the speed at which the device affects the signal. The difference between the thuck and crack sounds.
The release is the rate at which the device lets the signal decay. The time the compressor takes to return the signal to below the threshold.
The output level controls the audio level after the compression happens.
Why compress? It can make your tracks sound smooth and more consistent, it can change the tone and quality of the source, and it can change the room sound!
Compressors are dangerous and can kill an entire mix. Don't abuse them!
Compression is distortion! They are the same thing!
I love my group. We have our ups and downs, but we all have learned how to work collaboratively and effectively together to make the best recordings we can.
Compression is awesome. How did I not know this before?