ProCo Rat2

The ProCo Rat is a classic distortion pedal, prized for a smooth, thick, high-gain sound with plenty of gain on tap, and one owner calls it simply the best distortion pedal and fairly priced. Its quirk is the Filter knob, a high-pass that works backwards and is darkest fully clockwise, so owners set the distortion where they want it and then back the filter off to bring the grit and clarity back. It covers a wide range: rolled back it edges toward crunch, and cranked or pushed with a tube screamer or SD-1 in front it moves into tight, near-fuzz territory. It is famously used as a front end for Fender amps and stacks well with other drives, though a few owners admit they struggle to dial it to their own taste. The line runs from the standard Rat2 to the Turbo Rat and Fat Rat, and it has spawned a long list of clones.