My experience with compressors for your consideration...
Tried a stock CS-3 and it sucks too much tone to be usable. Definitely must mod. The Marshall Compressor is surprisingly good. Sounds good, quiet, does a decent Dyna Comp, and the 'Emphasis' knob is a great addition. It helps you er... emphasize the frequency you want to compress, so say if you want the highs to ring out you emphasize the lows. Very versatile.
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Well I like the Dyna Comp type compression so the Keeley works for me. Works fantastically for cleans and light grit... especially when you're doing stuff like plucking. Harmonics ring out really nicely.
For heavier tones it's really a matter of taste. As mentioned before Dyna Comp type compressors take away some high end to give a more rounded tone... well it works well for cleans, a lack of highs in distorted tones can mean a less crunchy distortion. An overly compressed, squished up distortion sound can sound really weak and farty... especially when you are playing rhythm.
I usually set my compressor's sustain knob below 9 o'clock. Anymore and my distortion sounds suffer.
I also find that compressors usually work better with single coil or lower output pickups cos hot pickups can overload the compressor and cause an overly compressed sound lacking in dynamics. That said an attack control (like that on the MXR Super Comp and the Marshall) does much to alleviate that worry.
As much as I love Dyna Comp type compression, many people find that kinda sound too squished. Furthermore that pedal is not exactly versatile and not without its shortcomings. Many new pedals have done much to address them. So no... Dyna Comp doesn't own everythin, it's a matter of taste
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BrokenWingz, have you tried a compressor before? I suggest you try a few in stores and maybe borrow one for a more extensive test on the nature of the effect (esp at performance/jamming volumes). It's good to do research but at the end of the day you still need to try one out before plonking your money on any effect.
And oh Harmony Central reviews... take em with a few spoonfuls of salt man :roll:
i don't know your budget but I do recommend the Marshall compressor. Another one to consider and find more info abt is Barber's Tone Press, which has a blend control so you can adjust the compressed sound with the uncompressed sound. Haven't tried one but it looks interesting. Rave reviews everywhere. If you are really interested in a Keeley (which is not very versatile or subtle, but does the Dyna Comp thing pretty damn well) I can set you up on a date with mine. Not selling it though. Just drop a pm.