This was inspired by samer's thread.
Can someone explain how the knobs interact
Level and tone are self explanatory but what do sustain and attack do and how do I get that "spank" out of my tele and strat.
and then what are the advantages of using a two-knob vs. a 4 or 5 knob version.
and last but not least what are some recommended settings? I have a Boss CS-3 if that helps.
In general, a compressor reduces the signal level once it exceeds a certain level. Attack controls how quickly it reduces the signal. Sustain is some combination of release and ratio, where release is how quickly after the signal drops below the threshold it stops reducing the signal, and ratio is how much the signal is reduced. The 4 and 5 knob versions give you more control over those parameters.
As for settings.... I pretty much hate compressor on guitar, so I am no help!