Monte Allums Proco Rat2 Mod

This mod isn't that hard so long as you have decent solder skills. The Rat2 is still a well built pedal even though they're made in Chine. But what isn't these days? One issue is you need to be cautious getting the knobs off the pots. You have to heat plastic knobs up with a hairdryer and then pull them off the posts. If you pull the post out of the actual pots you have install new pots that are only available through Proco sound.

The pedal is ok to start with but these mods really give you a lot more tonal options.

I'm going with a sold 9. The stock rat2 was ok but it didn't really jazz me too much. I did the mods and really liked a lot of the sounds I was getting. I did a A/B test comparing the modded Rat2 with a Barber Direct Drive and found I actually like the modded rat better. It also was more versatile and had a lot more gain than the barber(which is an excellent pedal on it's own). The Barber may have been a tad more transparent-if that's the right word-. But it was close and the rat is capable of many more sounds.

I do have one gripe abou the tri-mode option which is a toggle that allows you to switch between three gain types. All three have different volume levels. The diodes are the quietest, the LEDs a little louder, and the single diode is very loud. You end up having to adjust the volume with every toggle switch which could be a pain during a gig. However usually you find you sound and sort of leave it there.

You can check out sound clips on Monte's site for yourself and, yes, they are pretty accurate.

It sounds very good to my ear. I'm playing a couple of MIA strats with CS single coil pups. I run that through a Carvin Nomad and a Kustom '72 Coupe at the moment.

Despite what some say the Rat2 is still one of the sturdier pedals built out there. The PCB board is high quality and so long as you do a decent job soldering the pedal should outlast just about any musical peice of equipment. The metal case alone is very thick steel which also makes the pedal weigh about twice what a normal stomp does. But could cold probably run it over with a truck and it would still work.

The people at Proco sound are great. I screwed up my pots during the mod and called customer support to order new ones. I fully expected to get a hard time because I had modded a new pedal but the folks there are very nice and he sent me new pots free of charge! We even talked about popular mods and pedals and I came away with a great feeling about the people that work for this company.

If you have a stock pedal and there was ever an issue I have no doubt the company would stand behind it. Heck even on my modded pedal they were very accomodating. They could have just as easily told me to bug off since I was the one who ruined that component of the pedal, or even charged me for the pots which you can only get from them. But they didn't. This has been my best experience yet dealing with a guitar, amp, effect company bar none. These guys are great.

This is my first Monte Allums kit. It was easy to follow and Monte is very good at responding to emails regarding help/support for doing his mods(usually the same day). The components are all quality parts and the instructions are pretty clear and easy to follow. I'll probably do a couple of more since it's kinda fun to mods these pedals and a heck of a lot cheaper than buying botique pedlas that probably have the same modded components anyway.

Bottom line is that Monte's Rat2 FatRat mods are worth it and really give you a great sounding distortion pedal. I've got quite a few distortion/OD pedals. A fulltone OCD, the Barber Direct Drive, an MXR classic Fuzz, and a DOD American metal. The Fulltone OCD handles the tubescreamer tones and the rat handles the heavier stuff. The Barber is probably going back to the store since it's kind of redundant with what I have and frankly it's not as good a "distortion" pedal with my rig as the modded Rat2

In September 2007 I submitted review of my Dirty Rat mod with the LM308N supplied by Monte. Whilst it significantly improved the pedal I was still not happy with the limited usable sweep of the Filter control. The sweet spots were crammed between the 2:00 and 3:30 settings. Beyond this and the sounds became muddy and murky; back the sounds became abrasive and harsh.

So I figured perhaps part Monte's Rat Tri-gain mod would improve matters. The Rat which the Allums kit modifies shares the same circuit as the Dirty Rat apart from the clipping diodes. Therefore I purchased the Tri-Gain Rat instructions which were up to to the usual exemplary standards I have come to expect.

Clear illustrations, component identification sheet and a table of the changes together with explanantions of what each mod did. Impossible to fault.

Having used Monte's CS-3, SD-808 and BD-H2O mods in the past couple of years, the Dirty Rat component replacement was very straightforward. More so because the opamp had already been changed...

Monte also suggested adding an optional 10k resistor to the filter pot. The instructions, speed of delivery and additional info all add up to a perfect 10.

Changing three capacitors added further smoothness to the Dirty Rat which had improved a great deal with the addition of the LM308 opamp.

The usable sweep of the filter control is now far wider and I am finding other great sounds beyond my usual choices. There is little apparent noise across the tonal spectrum from smooth overdrive/distortion to an edgy fuzz. That's Germanium clipping diodes for you.

The sonic gulf between the Dirty Rat and my mid-80s Rat2 is nowhere near as great as it was. Obviously there will be differences if only because of the different clipping diodes (Silicon in the Rat2, Germanium in YDR). All things considered the improvement to the Dirty Rat is nothing short of mighty impressive.

I use the YDR with a Hiwatt DR103, Lab Series L7 and Marshall MG30 amps. Guitars are HSS Strat, 2 x Les Pauls and 2 x Hamers. The pedal is fitted to a mains powered pedalboard comprising:

Boss TU-2 >> Guyatone ST-2 compressor >> Morley Powerwah >> Keeley SD-1 >> Dirty Rat >> Digitech DigiVerb.

It is a ProCo chassis, so built like a scaled-down Tiger tank. Over 20 years of use with the Rat2 seems to indicate the YDR's pedigree for ruggedness and reliability. Fitted to a mains powered pedalboard means that potential battery death is not a problem. IF the YDR did die mid-gig at least with true bypass switching it would not black out the guitar signal. But frankly I can't see that happening.

I don't want to appear sycophantic but Monte Allums is amazing to deal with. Very prompt dispatch, superb products at RIDICULOUS prices and helpful beyond expectation. Monte's e-mails are a great example of courtesy and brevity.

If I could I'd give Monte the full Nigel Tufnell. But we'll have to settle for...

Stock the Dirty Rat was very harsh and raspy and I found it very difficult to find settings that worked across the whole fretbaord. Good bass meant nasty highs, sweet highs meant wooly, muffled bass.

With three capacitor mods and the LM308 transplant the YDR delivers. With a Strat it still sounds like a Strat, humbuckers sound bold and muscular and P90s want to rip your head off. However I still prefer the old Rat2 but there is no longer a sonic chasm between the two pedals.

The massive improvement in the filter sweep, the gain in sweetness and loss of the harsh raspy edge fully justifies the mods. It is a pity ProCo don't make 'em like they used to. The Monte Allums mods prove just what is possible.

I'm reviewing the Fat Rat2 Tri-Gain Mod.

As far as operation goes--three knobs and a toggle, it's very easy to get the sound you want...or are allowed to get...

I'll give the original, "stock," new Rat2 an 8. The original, unaltered sound of the Rat2, even with the crap Op Amp, is pretty good. It's a solid pedal

I give the Monte Allums Fat Rat2 Tri-Gain Mod a 5. With the addition of the LM308N, the new caps, and the LEDs you are heading in the right direction; they are drastic improvements. The diodes and Tri-Gain switch are where my issues begin. The Switch:
Mode 1-asymmetrical clipping with LEDs sounds GOOD.
Mode 2-single diode, volume boost is LOUD and bad--in a bad way.
Mode 3-pseudo-symmetrical clipping with silicon diodes sounds OK.
I have couple of problems with the diode section:
-1--I DO NOT UNDERSTAND the affinity for the 1N4002 silicon diodes!? Plenty of people may like them (obviously). However, to me, they are ANYTHING but "Tube Like." They seem to offer more of a "farting torn paper cup" vibe...you can get a good dose of this when you set the switch to the middle position (Mode 2)...and that's through any of my amps. I've modded numerous pedals, tried MANY different kinds of diodes, and the $0.10 1N4002s DO work OK in SOME pedals...but NOT this one...that's my opinion.
-2--The way that the Diodes are configured with the "Tri Gain" switch creates a redundancy where only one side will conduct. Yes, the asymmetrical clipping that occurs when selecting the LEDs (Mode 1) will sound good, but only one of the LEDs will actually be a significant, conducting addition to the circuit--it seems a waste of perfectly good diodes.

Now, if you modify the Mod, it's a 9. I kept the original diodes, use one (1) LED. This is actually VERY close to the Keeley Mod. I have a Keeley Modified Vintage Rat, which I LOVE. Now I LOVE my Rat2 as well...and for only $23 instead of $65.

With a delicate touch and mad soldering skills, it will last. Be careful with the connection wires. You can only get a couple of bends out of them before they break, and you have to re-strip and re-solder. I did have a problem with the supplied switch, they're CHEAP. One of the terminals broke off with minimal pressure and I had to replace it with a Radio Shack part.

Haven't dealt with them, yet. They seem friendly and helpful

I play bass and guitar in lo-fi indie bands and some sludgy, fuzzy stoner-esque projects. I use modified Epiphone guitars, numerous distortions and fuzzes (including a Keeley Rat, Keeley BD-2, VOX Valvetone, DigiTech Bad Monkey, Malekko B:Ass Master, Nobels ODR-1, etc.), modulation effects and delays into older tube amps (Fender Twin, Traynor Reverb Master, VOX Cambridge, Direct using a Line6 PodXT). The Modified Monte Allums Rat2 Mod is a wonderful addition. It cascades well with my other distortions. If it were stolen, I would buy another Rat and probably Monte's kit. It's a good deal for all of the components.

While I didn't like the "out-of-the-bag" modification, it provides a good starting point, tools and insight to make a good pedal, GREAT.

...(enter sunshine, happiness, squirrels, and pleasant orchestral fanfare)...

This account is for a Monte Allums supplied LM308N opamp that was fitted to a Proco YOU DIRTY RAT. The Dirty Rat uses the same OP07DP opamp as the current Rat2 and to my ears it was very harsh, raspy and unpleasant to the ears. Maybe switching to the semi-legendary LM308N chip might change things...

The LM308N opamp came with an 8-pin socket that replaced the original OP07DP in the circuitboard. Having used three of Monte's mod kits there were no real fears about unsoldering the chip and fitting the socket. The advice posted about the Allums RAT2 kit on Harmony Central was heeded as Proco solders its components a lot more rigorously than Boss.

Compared to the Rat2 the Dirty Rat had a harsher, more abrasive distortion which was nowhere near as pleasing to the ear. A brief consultation with Monte Allums confirmed my suspicions about the factory-fitted opamp. Both the current Rat2 and YDR use the OP07DP chip whereas the early Rat2 carried the LM308N which lies at the heart of its powerful but musical distortion. Knowing that Monte Allums??? Rat2 mod kit includes the LM308 chip together with other components it seemed pretty obvious that simply changing over the chips could make a significant difference to the sound of the Dirty Rat. In September 2007 that is exactly what happened when the Allums??? supplied 8-pin socket and LM308N opamp were installed.

Result: - a smoother distortion sound without harshness or rasp. Definitely not the Rat2 sound because of the YDR???s germanium diodes and the compression circuit but a vast improvement on its original brash, brittle and unpleasantly edgy sounds. This is now a stompbox that will be used with far greater abandon than previously.

If my other Allums mods AND the proven durablity of Proco stompboxes are anything to go by then reliability will not be an issue. Care and precision whilst soldering is the core of pedal mods. My RAT2 is over twenty years old and still delivers. I have the same aspiration for the modded Dirty Rat.

Monte Allums is a swift and helpful responder to e-mails. Despite asking some really stupid questions he is always courteous and polite in his replies. A rare commodity these days, I feel.

The Dirty Rat fell into disuse when I swapped it for the Allums SD-808 conversion on my pedalboard. When I put together a second board using my pedal spares box, I was reminded why I had stopped using the YDR:- a harsh, abrasive distortion which was nowhere near pleasing to the ear. A brief consultation with Monte Allums confirmed my suspicions about the factory-fitted opamp. Both the current Rat2 and YDR use the OP07DP chip whereas the early Rat2 carried the LM308N which lies at the heart of its powerful but musical distortion.

The result of the opamp change was a far smoother distortion sound without harshness or rasp. Definitely not the sound of the Rat2 because of the YDR???s germanium diodes and its compression circuit. It is a vast improvement on the original brash, brittle and unpleasantly edgy sounds. This is now a stompbox that will be used with far greater abandon than previously. I think that says it all really.

Did I mention the opamp and socket only cost $6.95?

Monte's instructions are top notch, follow them and everything should go well. Having done the GE-7 mod before this one gave me the confidence and patience I needed. The Rat's board is definately of a different stripe than a Boss. It has way more solder to remove and is a weird yellow color that at times makes it hard to see the leads so a little more time and care are required.

The stock Rat is terrible sounding.His mod does what he says it does. It smooths out the jagged gain,warms it up and adds more bass.I only have one complaint. For my tastes and the way I'm using the pedal in front of my amp (a Mesa Nomad 55), I didn't like the .01uf cap in there. It made the pedal too nasal sounding. Think Ted Nugent's solo sound in Strangle Hold. Cool sound but not for every song. I couldn't dial it out so I just put the stock cap back in and that fixed it for me. Now the pedal is a keeper. I use it to add fatness to my gain channels.

The Rat is built like a tank and my solder joints are good so I don't expect any trouble.

Well Monte is prompt to get out the product to you and for my GE-7 mod he responded to my e-mails quickly. Good service.

I play a large variety of music. This pedal definately goes for the rock and roll to metal side. Not a wide range of gain. It goes from 0 to 10 in about 1/2 of the knob's range. But I like it so I'm going to keep it. Blending it in with the gain on my amp gives me a fuller sound. It adds some nice harmonics to an already good sounding amp.