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The Pro Co RAT started life in 1978 as a repair-shop experiment in Kalamazoo, Michigan, and became one of the three or four distortion circuits everybody else measures against. Its filter control, running backwards from a conventional tone knob, is a large part of why it sounds like nothing else. Our coverage reflects that influence more than the company's release schedule: the RAT is a fixture of our distortion and gain-stacking guides, and a reference point whenever a new boutique fuzz claims a lineage.
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- RAT
- RAT2
- TurboRAT
- You Dirty RAT
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Pro Co FAQ4 questions
What is the Pro Co RAT?
A distortion pedal, and one of the most influential ever made. Prototypes were designed by Pro Co engineer Scott Burnham in the company's rat-infested basement in Kalamazoo, Michigan, with early units built to order and full production starting in 1979. Guitar World credited it with creating the template for what distortion sounds like.
What is the difference between a RAT and a RAT2?
The RAT2, released in 1988, is the current production model and the version most people mean by 'a RAT'. Earlier RATs differ in enclosure, control layout and some component choices, which is why originals attract collector prices; the circuit's essential behaviour is the same family.
What are the other RAT variants?
Pro Co has released several: the TurboRAT with harder clipping, the You Dirty RAT with a more compressed, fuzz-like voice, and various reissues and limited runs. The filter control, which works backwards from a normal tone knob, is common to all of them.
Why do so many companies make RAT clones?
Because the circuit is simple, distinctive and enormously popular, and it sits in a useful space between overdrive and fuzz. Once a design becomes a reference point, other makers build their own take on it — the RAT is in the same category as the Tube Screamer and the Fuzz Face in that respect.