Odd this should come up...I'm just working up a compressor shootout.
ADR's description of the functionality is spot-on, as is OOPicker's report of adjusting the beast so that it's not terribly apparent, and is only noticed when absent.
But both of those descriptions somewhat undersell the use of compression for a noticeable effect, rather than as a problem-solver. Sometimes indeed I do want compression to tame attack, tone, or to boost dynamics that would otherwise get lost...to civilize and smooth both my tone and my inconsistent playing.
But other times, you want compression for much more obvious stuff – for the way a note sucks down with a slurp on attack, and then swells up beneath when it would otherwise decay. You hear this all over Nashville Tele chicken-pickin' approaches, where compression vastly increases the percussive bark a Tele has already. But it goes by so quickly you don't generally realize it's compression.
The one place I can think of where compression really stands out in a recording, used in a more legato context, is the first note of Steely Dan's "Hey Nineteen," that Strat note that pops and then swells.
And compression has long been used to make guitar parts sit in mixes without eating everything else, but still punch through with authority.
Anyway anyway...I turned a DynaComp on in 1978 and didn't turn it off till I got a DOD MilkBox a few years ago. That one stayed on till I got the TonePress. I mean, I literally didn't play guitar without compression in all that time. Just recently I've realized that Gretschs do a little compression all on their own, and have come to be occasionally annoyed at the way a compressor can mask dynamics and mess with the natural evolution of attack, sustain, and decay.
So I've been playing without it most of the time. IF I had studio-quality compression on the floor (like an RNC or a Joe Meek), so that it was just subtle tone-shaping, I'd probably go back to leaving it on all the time again...
As it is, just in the last week I've been playing with the TonePress's settings again, and have it close to that standard of transparency.
I also got the Janglebox last week, which set off my current compressor frenzy. The shootout will include the DynaComp, MilkBox, TonePress, and JangleBox. (Note how even the names of these pedals are compressed together.)
JangleBox is an odd duck. In its "normal mode" it sounds like a very slightly higher fidelity DynaComp, only it rolls off a small amount of high end by comparison. Its range of effect from subtle to obvious is very similar to the DynaComp's.
Its reason for being is the "bright" switch – and, indeed, when you're playing a 12-string and flip that sucker, it's 1965 and "Mr. Tambourine Man" is on the radio. It punches and jangles and pops.
But I find it a fatigueing sound, and don't leave it on for long. It provides an object lesson in what engineers did to position that 12-string, playing right down in the oft-muddy first-position vocal range, in the mix. Sounds to me like nothing but a judicious treble boost and simultaneous bass cut, with both frequencies chosen carefully to create that one jangling sound. It works...but other than that, the JangleBox doesn't impress me as an exceptional compressor.
The Barber remains the most transparent – and the most flexible – floor compressor I've used. It can just barely be there, caressing and smoothing your tone, or it can pop like a chicken-picker.
Nice box. If you have compression in your DNA, I think you'll like it.
The shootout should have been done a week ago, but I'm distracted by too many toys to play with.
