Hi there. I want to buy a compressor pedal and a friend of mine (actually a sax player) told me that this was going to be a VERY important part of my tone, but I don't know anything about compressors so can anyone help.
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A compressor does many things, depending on the model/make/type/etc... but in general, your typical compressor will take an incoming signal (for example, what comes out of your guitar) and it will "even out" the signal so that all in all, the amplitude of the signal is fairly uniform (you can sort of imagine this as the compressor taking the incoming signal, and "squashing down" all the really high peaks; additionally, depending on the compressor and its settings, it could also increase low peaks). And it should be noted that the degree to which your signal is "squashed" depends on how the compressor works, the settings you use, etc.

So what does this really mean? Most obviously, it changes the way your guitar sounds. It helps keep your playing a fairly nice consistent-ness. And largely, most guitar players employ compressors to enhance their guitars sustain (sustain is basically a measure of how much/long a note rings when you play it; for example, if you play an A note and it sounds and very quickly fades, you could say your guitar has bad/low sustain; where as if you play an A note, and it rings out nicely for a decent amount of time, you could say your guitar has nice/high sustain). Sustain is important to a guitarist if you are playing things like chords, and particularly lead playing (if your guitar has bad sustain, when you hit that G note and let it ring in your solo, and it dies off after a second, obviously you'd want it to last longer, and a compressor can help you accomplish this).

My advice would be to head over to some guitar stores, ask if they have any compressor pedals... sit down at an amp, and try out a few brands (mess with the pedals settings, try it clean, try it with distortion, etc). No matter what someone says, you really won't understand its impact, or how it can help you without trying it out and hearing it with your own ears.
Last edited by CyBerAliEn at Jun 3, 2008,
I would get the keeley compressor once you learn a little more about them.
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