01—Pedal catalog
ProCo RAT 2
The op-amp hard-clipper whose filter knob runs from cutting bite to dark sludge: the most range-having distortion pedal under $100.
The cheapest pedal here that has genuinely changed music. Buy it without hesitation. Should be on more boards than it is.
02—On the bench
ProCo's hard-clipping distortion — the loudest, most aggressive, most versatile drive pedal made for under $100. The RAT was designed in 1978 by Scott Burnham at Pro Co and refined into the RAT 2 in 1988; the circuit is an op-amp gain stage into hard-clipping silicon diodes (early units used the LM308; current production uses an OP07), producing a distortion that's tighter and more focused than a Big Muff but more aggressive than a Tube Screamer. The 'filter' knob is a low-pass that runs backwards from a tone knob: clockwise rolls off treble toward dark sludge, counterclockwise opens it up to cutting bite. Used by Jeff Beck for cleaner overdrive (low gain, filter low), by Kurt Cobain for grunge crunch (mid-everything), by James Hetfield for early Metallica tone, and by Radiohead's Jonny Greenwood. Cheap, indestructible, and one of the most range-having drive pedals ever made.
- 01filter knob is a low-pass, backwards from a tone knob: right for sludge, left for bite
- 02at low gain, behaves like an overdrive
- 03at high gain, full-on hard-clipping distortion
- 04scoops less than a Big Muff — more midrange presence
- 05stacks well into a clean amp or a dirty one
03—Power
What it takes to run the RAT 2.
4mA at 9V
Low draw. Any standard 100mA isolated jack carries it with room to spare.
Typical published draw. Check the label on your unit for its voltage and polarity before you plug in.
- Voodoo Lab Pedal Power 2 PLUS →jacks 1-4 · 100mA
- Truetone 1 SPOT Pro CS6 →jacks 3-4 · 100mA
- Truetone 1 SPOT Pro CS12 →jacks 3-6 · 100mA
04—In the room
Where else this pedal lives.
- Jeff Beck
- Kurt Cobain
- Jonny Greenwood
- James Hetfield
- Thurston Moore
JHS PackRat if you want several RAT-family voicings in one box.