In 1978, the most versatile
and influential distortion pedal of all time was invented in Kalamazoo,
MI: the Proco RAT. Scott Burnham and Steve Kiraly first had the idea
after playing, repairing and modifying all the available distortion
pedals on the market. They wanted something that didn’t exist in the
mainstream product lines like MXR, DOD and BOSS. They wanted a pedal
that could go from overdrive to distortion and then all the way to fuzz.
By 1979 Scott had perfected the circuit in his RAT-infested basement
workshop, and the rest is history.
The PackRat is the ultimate
tribute to the 40+ years of rodent evolution and its impact on the
guitar’s sound. Artists from every genre have used the iconic tones in
this unassuming black box to create their sounds, including Nirvana,
John Scofield, Pink Floyd, Metallica, REM, the Eagles, Jeff Beck and
Building on our Multi-Mode pedal series that includes
the Muffuletta and Bonsai, the PackRat uses the same unique digital
runway system to direct the paths of 261 components through 40
individual switches. This means that when you choose one of the nine
legendary or rare modes, you are playing fully analog circuits that
perfectly replicate that mode, even down to the aging components (also
known as component drift). If you purchased these nine hard-to-find
pedals on the used market right now, you would pay around $4,000. When
you put it that way, $249 sounds pretty reasonable.
Let’s take a look at the controls.
operation of the PackRat is about as simple as it gets. The “Volume”
control adjusts the overall volume of the pedal. The “Distortion”
control lets you raise and lower the amount of gain or distortion that
the circuit produces, and the “Filter” control allows you to brighten
and darken the sound of the overall effect. This is effectively a
simple, low-pass filter. Lastly, we have “Mode” control. This is a
stepped pot that clicks into place as you scroll through the nine
legendary versions of this circuit. As you change the mode, the analog
circuitry is rewired, resulting in brand new values of resistors,
capacitors, diodes and op amps.
I’ve put several years of research into the history, circuit topology
and version history of the RAT, I know that my findings may still ruffle
some feathers. I’m okay with that.
I have tracked down over 100
different RAT specimens for study, and I’ve performed almost twenty
hours of interviews with former ProCo employees about the circuit
design, evolution and production of this pedal series over the decades.
And basically? A lot of the widely accepted “facts” about the
differences in RAT versions, including some of my own beliefs, were
wrong. Most assumptions about how specific RAT models sound different or
better than the rest are, at best, misinformed. Generally speaking,
they’re flat-out incorrect.
To find the facts and give this
circuit the proper understanding it deserves, every RAT model ever made
(and quite a few prototypes that never saw the light of day) were
obtained and studied in great detail. I wanted to understand the exact
production differences over the years, so we disassembled the units,
analyzed them using state-of-the-art Audio Precision equipment, measured
individual components, built comparison charts, traced each circuit and
closely examined the branding, logos and other identifiers of change.
As far as I know, no one has ever gotten close to the level of research
that we performed between 2018 and 2021.
Reliable sites like Reverb.com
had inaccurate timelines with incorrect pictures of the respective
models. Even ProCo’s own history timeline was missing tons of details
about the RAT variations that have been made over the past 40 years. And
Wikipedia?… No. Just no.
There’s a reason for that.
vintage unit is typically dated by reading the manufacturer codes on the
back of the pedal’s potentiometers/knobs. Unfortunately, this is a
flawed dating method. ProCo would have ordered thousands of
potentiometers, and in doing so, many pedals were made with parts pulled
from backstock at least two to three years older than the actual pedal
being dated. In short, this means that you’ll see V1s, V2s, V3s with
dates that overlap with each other’s true production years. Combine this
with decades of people incorrectly “remembering” what RAT model sounds
the best, and you have a historically inaccurate hot mess on your hands.
To properly build an accurate timeline and database of changes, I
dated the pot codes, dated their components when possible, interviewed
respective people involved in the eras of production and referenced over
1,000 online sales photographs, and studied the prototypes and the
evolution of the engineers’ design ideas. I did everything possible to
build an airtight case for my work and to not rely on any prior dates
and timelines. The results may not be perfect, but they’re pretty darn
close. See my full biographical timeline with photography and specific
details of my work here.
The PackRat Modes:
1. The OG V1 (1979-83)
OG mode is a perfect recreation of the first production RATs ever made.
This era of roughly four years covers what is referred to historically
as the V1 models.
Early V1s are also known as the Fringe Logo
model and can be identified by the letters R-A-T being in all capital
letters with a slight fringe graphic coming from the typeface. The V1
also has small silver capped knobs and a Tone knob instead of the more
familiar and later produced V2 Filter control labeling. From a circuitry
standpoint, the V1 and V2 Big Box models are practically identical
except that the V1's Tone control increases treble as you turn clockwise
while the V2's Filter control decreases treble in that direction.
switching to the OG mode, you are activating the exact circuitry of my
1979 V1 Fringe Logo model, including the accurate Tone control rotation
Let me take a moment here to clarify: the V1 and V2 models are the exact same circuit, and simple adjustments to the Tone/Filter control can achieve identical sounds from each unit.
know that the super nerds are going to ask why we didn’t include a Bud
Box mode. Basically, I’d consider the Bud Box RAT to be a V1, because it
is almost identical other than having an input buffer as well as a
couple of extra parts.
2. White Face V3 (1984-1986)
1984, the RAT transitioned into a smaller square enclosure with a new
white rectangle logo. The word RAT was in all black caps inside the
white rectangle; this model gained the “White Face” RAT nickname due to
this aesthetic. In 1986, this same model had a logo change that simply
inverted the white and black colors, resulting in the more familiar
white rectangle outline and font on the black enclosure.
“White Face” model has gained a reputation as one of the holy grail
RATs, and it even spawned a reissue in the nineties. The irony is that
it is the same exact circuit as the previous Big Box V2 and the
following “Black Face” 1986, as well as the 1989 RAT2. The “White Face”
V3 update was a purely cosmetic change due to screen printing errors
that needed to be solved. ProCo knew that the world wanted smaller
pedals in the wake of brands like BOSS, DOD and Ibanez gaining more and
more market share, and they wisely cashed in on the trend.
this said, why would I put this particular version in my PackRat if it
is not any different than the OG? For one, nostalgia is a powerful
thing, and secondly, this mode will switch to the reverse orientation
V2-V3 Filter control with an entirely different feel and experience. In
many ways it widens what many consider the sweet spot for the most
beloved RAT tones.
Like you, I want to believe in magic models of
my favorite pedals, but sometimes the magic is just because we like the
look or the user experience of one version over the other. It’s okay to
admit that and move on.
3. Turbo V5 (1989)
heart of the RAT’s tone comes from a design technique called
symmetrical hard clipping. In this approach, a simple amplifier circuit
amplifies the guitar’s signal and pushes it across a pair of clipping
diodes. The result is that these diodes clip off the top of the waveform
of the guitar and create a type of square wave distortion. Every RAT
until 1989 utilized a typical silicon diode, just like the DOD 250 and
BOSS DS-1, but the new Turbo RAT used LEDs (Light Emitting Diodes). Yup,
these are the same LEDs you see in flashlights, your car’s dashboard,
DVD players and almost every other electronic device on earth. This
technique was a first in pedals (the same clipping style was used in the
Marshall Guv'nor) and offered a completely new RAT experience.
silicon diodes in previous versions have a lower forward voltage,
resulting in a faster and more extreme clipping of the waveform. You
could say this type of diode creates a very saturated tone. The Turbo’s
LEDs have a much higher forward voltage, so they don’t activate or clip
the signal as fast or as hard. It takes more signal to reach the point
where they will “cut off” the waveform, which causes the phenomenon we
know as touch sensitivity. You can set the Distortion lower, and as you
play lightly, you will have an overdrive tone; dig into your guitar and
play hard, and hear more clipping/distortion.
It is also worth
noting that this model was the first RAT that offered the sloped
enclosure that we see today. It also featured the new on/off status LED
that had made its debut one year earlier in the 1988 RAT2.
4. BRAT V6 (1997)
1997 ProCo got into the budget pedal game by releasing the BRAT and the
Guitar Center exclusive, Roadkill. These two identical circuits with
different and very nineties grunge aesthetics have the most changes so
far in the evolution of this legendary circuit.
added an input buffer circuit and soft clipping (inside the loop of the
op amp) on top of the standard hard clipping of the previous RATs. We
also see a return to the opposite taper/rotation Filter control and
several capacitor value changes that alter the frequency response and
characteristics of the distortion.
5. Dirty V7 (2004)
2002, ProCo released a 2-in-1 RAT pedal called the Deucetone. This
pedal allowed you to have two completely separate RATs and activate them
independently or stack them together. It also introduced two brand new
sounds into the RAT topology: “Clean RAT” mode and “Dirty RAT.” Due to
the popularity of the “Dirty RAT” mode, they released a single pedal
called You Dirty RAT that featured that single setting in a standard
sloped RAT enclosure. This circuit utilizes germanium diodes in the
symmetrical hard clipping section of the circuit. This technique gives
the most saturation and waveform clip-off of any version ever made.
addition to the diode changes, this model has several different
capacitor value changes resulting in a different distortion character
6. LA (1986)
In 1986, Ibanez
released the 10 Series line of pedals that included three RAT style
pedals. The Super Product and Fat Cat held the position of accurate and
traditional RAT style pedals, while the quirkier LA Metal was, in my
opinion, one of the best-modified RAT circuits of the eighties.
includes a great input buffer, several key capacitor changes for
frequency response, and no clipping diodes at all. The distortion is
produced by overloading or “clipping the rails” of the op amp.
I don’t play LA Metal, and I’m guessing you don’t either, but I promise you will love this mode!
7. Landgraff MO’D (1999)
1999-2000, a man named John Landgraff started building pedals by hand
in Pensacola, FL. Each one painted with a unique swirl paint job and
wired point to point; John’s pedals were and still are the true
definition of boutique and gained a reputation for sounding amazing. His
most popular pedal was the Landgraff Dynamic Overdrive, a take on the
Ibanez Tube Screamer, but my favorite was his distortion pedal that he
called the “MO’D,” a distant cousin of the RAT and a really fantastic
pedal in its own right.
8. Caroline (2010)
few years after starting JHS, I purchased a fascinating distortion
pedal from a brand new company out of South Carolina. I remember jumping
on the phone and geeking out with the designer and head of the company
Philippe Herndon. We talked about the circuit, his love for RATs and his
clever take on the circuit. That pedal was called the Wave Cannon and
when I started the PackRat project, it was obvious that Philippe was the
friend I should bring along for the ride.
9. JHS Mode
2003 I managed a tiny guitar shop in Northwest Alabama. One day a man
walked in with a vintage Small Box RAT and said he wanted to sell it.
When the shop’s owner said he wasn’t interested, I said I was. I bought
that RAT for $15, and this is most likely the single event that led me
down the pedal collecting rabbit hole. That pedal stayed on my board for
a decade, and when I started modifying and building pedals in 2007, I
opened it up, learned the circuit and modded it to reflect a different
kind of sound. Parts of that modification became the now discontinued
JHS All American and the long-running JHS PackRat modification that we
performed on thousands of RAT pedals from 2008-2018. The JHS Mode lets
me keep what makes the RAT unique and add in a few of my personal