In 1978, one of the most versatile distortion pedals of all time was invented in Kalamazoo–the ProCo RAT. Scott Burnham and Steve Kiraly had the idea after playing, repairing, and modifying all distortion pedals on the market. They wanted something that didn’t exist yet at MXR, DOD, or BOSS, a pedal that could go from overdrive to distortion and all the way to fuzz. By 1979, Scott perfected the circuit in his rat-infested basement workshop. The rest is history.
The PackRat is the ultimate tribute to 40+ years of RAT evolution and its impact on guitar’s sound. Artists from every genre have used this iconic and unassuming black box to create their tones, including Nirvana, Pink Floyd, Metallica, REM, the Eagles, Jeff Beck, and Radiohead.
The PackRat uses the same unique digital runway system featured in our other multimode pedals (Muffuletta and Bonsai) to direct the paths of 261 components through 40 individual switches. This means when you choose one of the nine legendary modes, you are playing fully analog circuits that perfectly replicate that mode down to the aging components. If you purchased these nine hard-to-find pedals on the used market right now, you’d pay around $4k. The Pack Rat at $249 saves you thousands!
Controls
Using the PackRat is straightforward. “Volume” adjusts the overall volume of the pedal. “Distortion” lets you raise and lower the amount of gain or distortion. “Filter” allows you to brighten or darken the sound of the overall effect, acting as a simple low-pass filter. The “Mode” knob is a rotary switch that clicks between each of the nine legendary RAT versions. As you change the mode, the analog circuitry is rewired between different values of resistors, capacitors, diodes, and op-amps.
Research I obtained over 100 different RAT specimens for study and interviewed former ProCo employees about the design, evolution, and production of the RAT. Many of the widely accepted “facts” about the differences in versions or sounds, including some of my own beliefs, were misinformed at best. Often, they’re wrong. Reliable sites had inaccurate timelines with incorrect pictures of the respective models. Even ProCo’s own history was missing tons of details about changes made to the RAT over the past 40 years.
To find the facts and properly understand this circuit, we obtained and studied every RAT model ever made (including some prototypes) in great detail. We analyzed them using state-of-the-art audio precision equipment, measured components, built comparison charts, traced each circuit, and closely examined the branding, logos, and other changes as precisely as possible.
Vintage units are typically dated by reading manufacturer codes on potentiometers and knobs. Unfortunately, this is a flawed dating method. ProCo would have ordered thousands of potentiometers, and many pedals were made with parts that were at least two or three years older than the production date. This means you’ll see v1s, v2s, and v3s with overlapping dates. Combine this with decades of people “remembering” what RAT model sounds the best, and you’re in a historically inaccurate hot mess.
To properly build an accurate timeline and database of changes, I dated components when possible, interviewed people involved in the eras of production, referenced over 1,000 online sales photographs, and studied the prototypes and evolution of engineer design ideas. I did everything possible to build an airtight case for my work and not rely on any prior timelines. The results may not be perfect, but they’re pretty close.
