History of the ProCo RAT Pedal and Myths Debunked

[Deftone]

If you really want to nerd out on the RAT....



Or read it here:

https://jhspedals.info/blogs/news/proco-rat-pedal-myths-history-and-timeline

Another, more concise version:

https://paulreno.com/pro-co-rat/

Version Walk Through:
Bud Box 1977-78
Dual Bud Box
Scott Burnham Ring-Mod Prototype (Bud Era)
1979 / Version 1-A "Fringe Logo"
1979 / Version 1-B "Tone Knob / Fringe Logo"
1979 / Version 1-C "Tone Control / Metal Knob"
1979 / Version 1-D "Tone Control"
1979 Juggernaut (and Reissue)
1981 / V2 "Big Box Filter"
1984 / V3-A "White Face"
1986 / V3-B "Black Face"
1986 / V3-C "No Brackets"
1987? / RAT2 - LED Prototype
1987-88 / V4-A "RAT2-LED-Flat Top"
1989 V5 "Turbo"
1991-2005 "Big Box Vintage Reissue"
1997 V6-A and V6-B "Roadkill / BRAT"
2002 "Duecetone"
2002 Era? "ProCo Preamp Prototype"
2003 "25th Silver Anniversary"
2004 V7 "You Dirty RAT" and Proto
2006 V8 "Solo" and PROTO RATZO
2008 V4-B "RAT2 Chinese Made Slope Enclosure"
2010 "1985 White Face Reissue"
2014 V9 "FATRAT"
2015 V4-C /4-D / 4-E "IKEBE 40th Anniversary Exclusive Colorways" (Japan Only)
2021 V10 "Lil' RAT"

 

[Deftone]

MYTH:

“You need to get a Woodcutter RAT, they sound way better.”

"There have been rumors flying around forums for decades about a legendary builder known only as Woodcutter. Allegedly, Woodcutter worked at ProCo in the late ’80’s and ’90’s and built the best RAT pedals of all time. But did he?"

"Here are the facts: yes, there were multiple builders working at ProCo when the RAT was originally released and yes, Doug Fetterolf (AKA Woodcutter) was one of them."


"Doug Fetterolf (AKA Woodcutter)"

"Every builder had a quality control sticker with a name that attached the pedal back to the builder in the event that the pedal didn't pass testing. Doug built pedals as a part time job; he was a school teacher, with a side hustle of cutting down trees and splitting logs. You know, working as an actual woodcutter. The main reason that Doug ended up with the Woodcutter nickname is because there were multiple guys named Doug working at ProCo at this time. It wasn’t meant to be mysterious or cool; it was just a way of telling the Dougs apart."

"We find Woodcutter Doug’s stamp on a ton of vintage RAT pedals, but are they magical? More importantly, are the Woodcutter RAT pedals significantly better than any of the others ProCo produced around this time?"

"Nope."

"From the sheer number of pedals that exist with the Woodcutter sticker/stamp, we can confirm that Woodcutter was a fast builder. Very fast. Kandy, the RAT production supervisor, says that he was the best builder they ever had. Gerry “Grape” Carpenter said that Doug “probably stuffed more RATs than anybody else there, because that's all he liked to do.” From a production standpoint, he was amazing. He built more RATS than any other builder in his era and did it while only working part time."

-Josh (JHS pedals)

https://jhspedals.info/blogs/news/proco-rat-pedal-myths-history-and-timeline

 

[Deftone]

MYTH:

“The early versions with tantalum capacitors sound way better.”


"This myth is a classic case of a guitarist needing something to explain an idea. Early RAT models used a certain type of capacitor known as a tantalum capacitor and were replaced eventually with normal electrolytic capacitors. The idea that these tantalum caps sound better is completely illogical and false. The up-to-20% parts tolerance from pot manufacturing is a much bigger factor in perceived tone change across various units than anything this minor component change could have caused."

"Despite Scott Burnham stating that these have no auditory difference from the later used electrolytics, guitarists just want to believe in magic. He said he only used them because he thought it was cool that NASA had them in their equipment."

-Josh (JHS pedals)

https://jhspedals.info/blogs/news/proco-rat-pedal-myths-history-and-timeline

 

[Deftone]

MYTH:

“A real RAT has an LM308 op amp; nothing else has the right sound.”

"This myth is one of the most frustrating as a pedal designer and as someone who has studied the circuit in great depth. The RAT circuit is effectively a simple op amp boost that sends its amplified signal across diodes that shunt to ground. This creates the sound known as hard clipping. One of the many unique things that the RAT has going for it is that the op amp is actually run at such a high rate of gain that it distorts before the hard clipping distortion is ever started. This gives a rich distortion tone that has lots of complex harmonics. This approach to design is actually due to a mistake that Scott Burnham made by accidentally placing a 47 ohm resistor where a 470ohm resistor should have gone."

"This small but wonderful mistake led to the RAT’s trademark sound. In the original units, a LM308 op-amp was used and many people use its existence much like the tantalum cap as a sort of physical explanation for the really great RAT sound they remember. This op amp was discontinued in the early 2000s, phased out of the RAT’s production around 2005 and was replaced with the OP07. Despite popular opinion and rumor, this OP07 is a perfect replacement for the LM308. Its response, slew rate and frequency attenuation are identical. Sadly, the arguments you see for this rumor are never scientific or controlled, they are based on memory or a simple ear test that compares two RATS. This is impossible to test accurately, as you need to use the EXACT same circuit and you need to perfectly switch between two op amps instantly. It’s been scientifically proven that just a few seconds between audio perception is impossible to hear, let alone compare."

"The other issue with this is that no two RATS sound exactly the same. To take that further, no two pedals of any make or model sound exactly the same with knobs at the same spot. You can pull any two RAT pedals of any era together with consecutive serial numbers, made on the same day by the same builder, and they will still sound slightly different with the knobs at the same positions. This is mainly due to parts tolerance and the fact that no two pedals’ components will match exactly, ever. (They usually have a deviation of somewhere between 5-20% depending on the components.) What this doesn't mean is that they can’t sound the same. You simply turn the controls a tad and you can find the exact same sounds in both. Pedal shootouts are a ton of fun (I’ve performed a few myself), but at the end of the day they are a woefully inaccurate approach to comparison and should not be considered a serious method of scientific analysis."

"My last and final observation about this myth is that claiming the LM308 is the sound of the RAT is a serious disservice to Scott Burnham’s amazing design and it invalidates the quality and approach to his idea. The RAT doesn't sound great because of the LM308; rather, the LM308 sounds great because Scott’s circuit used it well and it continues to use the exact replacement part OP07 in the same way. If you think a vintage RAT sounds better because of the chip, bear in mind that there are far bigger tolerances in play-- and the chip isn’t one of them."

"One last thing: even if you do find an old stock LM308 op amp in 2021, there is a VERY high chance that it is a counterfeit. I have studied several batches of supposed NOS LM308’s in my research, and this is a big problem on the parts market. We really should let this myth go because there are still pedal builders today that are selling RAT style pedals on the backs of them having this “magic” component while in reality, they’re probably just relabeled."

-Josh (JHS pedals)

https://jhspedals.info/blogs/news/proco-rat-pedal-myths-history-and-timeline

 

[paul-e-mann]

Wow @Deftone you really are Rat obsessed lol! I never knew there was so much to know about Rats! Here's to the Rat, may it live long and prosper!

 

[Deftone]

Wow @Deftone you really are Rat obsessed lol! I never knew there was so much to know about Rats! Here's to the Rat, may it live long and prosper!

I'm just obsessed for the moment. I've learned a lot about them, but I'll move on to something else soon.

Did you ever open yours up? Actually, you can probably see the build sticker and tone knob s/n if you just remove the battery door.

 

[johan.b]

I prefere the flat box versions.. it's not the opamp... it's the box... it was so ugly and clunky, it had charm... then they tried to make it prettier with the slope and the smaller knobs but with the same overall esthetics.. now it's just ugly...

 

[Geeze]

Despite popular opinion and rumor, this OP07 is a perfect replacement for the LM308. Its response, slew rate and frequency attenuation are identical. Sadly, the arguments you see for this rumor are never scientific or controlled, they are based on memory or a simple ear test that compares two RATS. This is impossible to test accurately, as you need to use the EXACT same circuit and you need to perfectly switch between two op amps instantly. It’s been scientifically proven that just a few seconds between audio perception is impossible to hear, let alone compare.

100% - same for speakers, amps & pickups. The hype and non scientific analysis or testing sells or unsells lots of gear. I see the same hype/unhype in the rifle world with decades of chatter about tight chambers, neck turning, specific bullet jump and bullet position in the case. Every system - in this case a rifle barrel - is unique. I describe them like women - may have the same plumbing but they are not the same. A 3 time national champion told me in the 90's - shooting wins matches. A perfect bullet, load or rifle doesn't. In guitar land as in shooting constructive practice and experience makes you better. Probably why I still suck...

Now I'm going to break out my RAT - resist the impulse to peek under the hood - and play it.

Russ

 

[NumbSkull]

The other issue with this is that no two RATS sound exactly the same. To take that further, no two pedals of any make or model sound exactly the same with knobs at the same spot. You can pull any two RAT pedals of any era together with consecutive serial numbers, made on the same day by the same builder, and they will still sound slightly different with the knobs at the same positions. This is mainly due to parts tolerance and the fact that no two pedals’ components will match exactly, ever. (They usually have a deviation of somewhere between 5-20% depending on the components.) What this doesn't mean is that they can’t sound the same. You simply turn the controls a tad and you can find the exact same sounds in both. Pedal shootouts are a ton of fun (I’ve performed a few myself), but at the end of the day they are a woefully inaccurate approach to comparison and should not be considered a serious method of scientific analysis.

WOW.
This kills every youtube gear demo ever.
Bang Bang UR DEAD.

 

[Deftone]

Now I'm going to break out my RAT - resist the impulse to peek under the hood - and play it.

Russ

oh come on...just have a peak. I think you can see the QC tag and the pot codes through the battery door opening.

 

[paul-e-mann]

I'm just obsessed for the moment. I've learned a lot about them, but I'll move on to something else soon.

Did you ever open yours up? Actually, you can probably see the build sticker and tone knob s/n if you just remove the battery door.

Here ya go, it's an 86 based on the pots

 

[Deftone]

Here ya go, it's an 86 based on the pots

That thing is cool. IIRC, very close to the 1st one I bought if not identical.

 

[sk8er4l2]

I had a blue Rat as a kid... I named her skittles.

 

[Deftone]

I had a blue Rat as a kid... I named her skittles.

I've had a couple pet Rats. I named the last one Steve.

 

[sk8er4l2]

I've had a couple pet Rats. I named the last one Steve.

That's funny cause I know a Steve who is a rat.

 

[PelliX]

I've had a couple pet Rats. I named the last one Steve.

Do you name your guitars? I name most of mine and Steve is my Strat...

 

[Deftone]

Do you name your guitars? I name most of mine and Steve is my Strat...

I just call them "The '79 LPC", or "The '67 SG"....stuff like that.

 

[Leee]

So…
I need to buy a vintage Rat now?

 

[Leee]

Do you name your guitars?

I only call them names when they piss me off.

 

[PelliX]

I need to buy a vintage Rat now?

Nah, the current ones sound exactly the same overall. The only vintage RAT I would buy would be the R2DU because they don't make them anymore - but not for the tone, just for nostalgia/rack pr0n purposes...

I only call them names when they piss me off.

I give them guy's names because I play fairly hard sometimes and I don't hit women. Steve, Frank, Woody, Paul, Brian, etc. I decided to do the inverse for my bass(es) because they like a friendly slap from time to time... My bass is called Lucy.

[Cue the misogynist insults coming my way...]