what the hell does a compressor do exactly?

[without a trace]

heyoooo im new here, i've got a presonus firepod and have been using it just to record some songs just to remember them and have them stored away for future use... now finally my friends are comin back from school and we are going to start recording, i've got enough mics and a fast computer.... do i need a compressor? what does it do exactly? not only in technical terms but how will something sound recorded using a compressor compared to something recording without using one.....

[Harvey Gerst]

Until the introduction of digital recording, most sound recorders had a very limited dynamic range. "Dynamic range" is measured from the softest possible sound (without hearing equipment background noise) to the loudest possible sound (before the equipment distorts). It was necessary to squeeze the dynamic range of the live music a little bit to fit the limited dynamic range of the recorders.

That's what a compressor does. It turns down the loud peaks automatically till the range equals something a bit more manageable. Then, you turn up the overall level (called "Makeup Gain") till it fits in the dynamic window of the recorder.

[jkokura]

A compressor compresses sound (duh). If used probably, it smooths out loud spikes in volume and intesity, while raising the lower volume sounds.

Think of a wave file's image....it's a set of spikes out from the middle...the middle represents no sound, and the spikes represent how loud sound is - small spikes are quiet, and loud ones reach farther from the middle. Basically, a compressor allows you to keep the sound from reaching out from the middle too far...you create a ceiling that the audio stops at...

There's a lot more to it, and how you create that ceiling and how you adjust can be a complex learning process... I definately don't fully understand it yet, but I'm starting to get the hang of it.

Jacob

[without a trace]

ahh haa i get it sorta.... that being said - and thanks by the way for helpin my newbie ass....

but is it still nescessary to buy a rack compressor? or can it be done using software just as well?

[pandamonk]

Can be done with software no problem.

[apl]

Here are a couple of useful articles:

one

two