Nemphasis VT-Comp Guitar Compressor
" . . Having set the Level control to match the bypassed signal, Compression and Attack turn out to be very interactive. Keeping Attack low exercises the basic compression ratio. As you increase the value you move from a subtle smoothing effect to a more noticeable effect that's great for all things funk, from vintage George Benson leads to a processed Aztec Camera/Haircut 100 style clean pop rhythm sound. Turning Compression past 12 o'clock gives a very smooth sustained lead tone; if you want to add a bit of bite, just start playing with the Attack control which governs how the effect initially interacts with your note. The flexibility here gives you a similar level of control to what you might have experienced with a Boss CS-3 (not an optical device of course, but still a popular one), but the overall effect is much more open, and the VT doesn't overly colour your sound. A high Attack setting with a low-to-average Compression setting delivers a very transparent enhancement... the kind of set-and-forget setting that may be a useful ‘always on’ option.
A list of just a few of the current pedal type compressors that I own. The first Compressor that I ever owned, an original 1976 MXR Dyna Comp, a Keely 2, and 4 knob comp, a Pigtronix Tone Comp, a Wampler Ego Comp, a Carl Martin Comp, 2 Xotic SP Comps, an Electro-Harmonix Soul Preacher, an MXR Custom Comp, and Super Comp, an EBS MultiComp, and a Rivera Sustain Shaman. However, the Nemphasis VT-COMP is hands down the most transparent, and musical pedal compressor that I've ever tried.
" . . . Overall, the compression is smooth and transparent — you might not notice it in action but you’d miss it if you turn the pedal off. A bonus is that there’s plenty of output level available, and with compression right down and level up, you can use the pedal as a very natural clean booster. With higher amounts of both knobs together, it’s a great amp driver."