is it a good idea to always use one? what do you mean by evening out the levels on the frequencies.... like if your playing some chords and then jamming a solo... the solo won't be too loud over the chords?
i never really knew what a comp. did until i bought one....it is definately worth it. I guess what i notice about it the most is that it "smooths" out the sound. not really sure how to explain it. when i play clean tones it really seems to tighten and level it up really nicely.

i guess i would say just buy it and u wont be disappointed
Slowhand 03/23/07
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usually chords are louder then single note solos. what a compressor does is make loud noises quieter, and quiet noises louder. so if you play some chords you can switch to some lead stuff and itll be just as loud. if you want a solo to be louder, you turn the compressor off. ta da... oh yea this site might help, maybe not http://users.chariot.net.au/~gmarts/fx-order.htm
It cuts high output signals and boosts low output signals. Simply put, it makes chords the same volume as single strings. They're also used as sustainers that don't add distortion or overdrive.
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As people have said, it tends to make the quiet bits of what you're playing louder and the louder parts quieter, so that overall sound is a lot smoother, it gets used quite a lot in funk music where the guitar parts might otherwise sound uneven, it is also used a lot on bass guitar to stop certain notes from booming out too much (that's why a lot of bass amps have compressors built in to them) if you have a sequencing program like Cubase you should be able to find a freeware VST compressor on the net that will give you an idea of what it does, it's surprising how much more professional a little bit of compression can make your own recordings sound.
^^^ very too, i always compress my clean tone no matter what, distortion not so much but i use alot of dynamics with distortion, it really makes you sound like you might know what your doing
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ESP Horizon Custom
Gibson LP Custom
Gibson V
Orange Rockverb 50
Mesa Triple Recti
Marshall JCM800 2210
yeah pretty much what everyone else said, but id like to add that compressors can really kill your dynamics, which is one of the reasons why not everyone uses them.
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