MOD YOUR PROCO RAT FOR UNDER $20

[@mattlawson714]

My favorite piece of gear is still my big-box Rat I picked up in 2005 for 60 bucks at Guitar Center. I only recently opened it up and it's a 1991 model. Needless to say, I won't be modding it, but I use it for almost everything with my humbucker-equipped guitar except super cleans. I've got a Bogner Shiva and it's so low-mids forward that the Rat does amazing things to the tone. And I can dial the mids back to taste with a simple EQ pedal. My favorite tone ever, for both chug and leads (with minor tweaks) is a Tubescreamer boosting a Rat into a tube amp on the verge of break-up. It's just.... special.

[@ethanleever9187]

Your playing in the demonstration is sickkkk

[@rocket_appliances]

Just did some of these, minus the chip and stopped before the fuzz mods. Really made the rat so much nicer! Thanks for the video!

[@stephenkeddy6849]

I had this mod done and it’s great. The crushing tone is worth every penny. I went through the website and they recommended someone to install it. After about a week and ONLY $80 I received it. Could not have been easier

[@MatthewChapmanMusic]

That’s awesome, man! Thanks for watching 🤘

[@statc0313]

What size LED do you use for swapping out the color? Serious question btw, im dumb

[@nick_be9159]

Is the .0033UF 500K or 500V or 1KV?

[@Rubenz-y4i]

Maybe you should do the comparison with diferent (compensated) volume knob vale. The mod obviously change the volume knob response or rate.

[@mostafazaghloul3293]

My friend just gave me his rat2 that was fried. I opened it and immediately noticed R1 was completely burnt. I checked the schematic and replaced it for a 1M ohm resistor. I was excited to see it work but its still not coming on. Bypassed, signal passes through, also everything else on the pcb looked good and seemed to pass a DMM test. Any clue what I need to do?

[@MatthewChapmanMusic]

Sure, just a few pointers, at least! I would try checking out the voltage on the ICs, those things can fry sometimes and it’s almost impossible to know if that’s the problem if you don’t have a multimeter or something like that. If signal is still going through, then it either sounds like a bad IC in the PCB, or possibly a bad solder joint on one of the wires. Doctoring a pedal problem is SUCH an annoyance sometimes, so good luck to you, and feel free to reach out with an update after you look at it a bit! Cheers!

[@reeveselectro]

That should be 100r resistor..it's part of the reverse polarity protection network and will blow if it's given reverse voltage... your 1m is simply not letting enough DC into the circuit replace it and it should work 🙏🙏🤘

[@w4dZ0o]

Your high end is now more hissy. Which for me, the reason to get a rat is it doesn't hiss. I could be wrong.

[@75YBA]

Just ordered mine. Used to see them in every basement in Kzoo. Coming off a 30+ year Big Muff addiction.

[@Dave79-be7ld]

One day at a time!

[@oldmanandguitar]

Am confused, every rat I seen so far has a Motorola LM308 in it, the rat clones have a LM308 in. Why did urs have a different chip?

[@EvilBlakey]

Because the Lm308 is discontinued because it's obsolete (for its intended purpose), the OPO7 is cheaper, more available, and sounds exactly the same. No, really. They sound exactly the same

[@TremorBear]

Your playing reminds me of Ty Tabor. Great video thanks.

[@dekzan]

I like it original. Nice info, may do a partial mod. Thanks.

[@thefuneralparade]

I prefer my rat to NOT be smooth and be a gain monster.dooming itself to black death

[@letch1529]

as intended

[@aarondaniels629]

great vid (I am only halfway)...I hope you do more pedal mod videos...I am super interested in this topic and nobody on youtube does it justice..you did great.

[@MatthewChapmanMusic]

Thank you so much @Aaron Daniels! This last week, I actually made 2 more pedal mod videos! And I do have a playlist on my channel of all my weird mod stuff. So feel free to check some of those out! Cheers!

[@aarondaniels629]

@@MatthewChapmanMusic awesome...thanks and please keep it up!

[@Holysquid2700]

would the EQ mod on C1, C3, C9 and C12 make this better for using on a bass?

[@MarkTorromeo]

Cool paint job.

[@gomezzz21]

Hi! Thanks for the info. I modified my rat clipping diodes. I have a two way switch. On one side I've got two leds and on the other I've got a single germanium diode. Sounds amazing but not the pedal is insanely loud. Do you know how I can rectify this?

[@spidermancereal]

Add resistor to the germanium side to lower volume.

[@Bluechipssssss]

Is there any high or mid high frequency loss after modding to increase bass? Just picked up a rat 2, considering exchanging for a Fat Rat just for the increase in bass. However, the official website for the fat rat it mentions: “Fat Switch: Provides a significant bass boost and simultaneous high cut”. Is there a mod to increase bass without compromising highs, mids or losing any sound?

[@MatthewChapmanMusic]

It’s hard to say, exactly. If you do the steps in this video but omit the resistors that add bass, it cleans up the circuit more while retaining the slight boost from all the gain and EQ parts of the mod. I really liked the sound of that! But if you need the extra bass, try a weaker resistor value and experiment a little! Monte Allums also sells a mod to make the Rat 2 more like the Fat Rat, and that’s definitely worth checking out. Has a toggle switch and everything!

[@Bluechipssssss]

@@MatthewChapmanMusic Are you referring to omitting resistor R5, or additionally omit the following capacitor mods that increase bass: C12, C3, C1 and C9? Thanks, I'll also check Monte Allums!

[@Bluechipssssss]

Ahhh just read on Monte Allums website : "Let me say right off that I am well aware that the new production RAT 2s are now made in China. The problems with these Chinese production pedals are well documented. The quality of the parts is very poor and I do not recommend you try to mod them. There are instances where the pots have simply fallen apart." Was your mod done to a made in China model? Not sure how to proceed. Thanks again!

[@MatthewChapmanMusic]

Omitting C1 and C9 was what I was referring to specifically. Doing everything but those gives you a really good sound. And as for what he had on his website, I don’t totally agree. Mine was a bought brand new and modded, so it was definitely the ‘cheap’ parts but you couldn’t tell 🤷🏻‍♂️ they’re all built the same man, so I’d just go for it. Pedals doesn’t have to be made in America to be modded, or to be good quality! Thanks for watching, and best of luck with your mods.

[@Bluechipssssss]

MatthewChapmanMusic Got it. Thanks again!!

[@DialupBBS]

First off, changing the 100uF electrolytic cap's value will do nothing to change the audio signal of the pedal. That capacitor is used in the power supply stage for filtering. No audio ever passes through it and increasing the value will change nothing in the audio path. Swapping C4 as you state will result in a recap and nothing more. RAT has a .0033uF (3.3nF) stock capacitor value, not .002uF (2nF). This capacitor is part of the Tone control stage and changing the value adjusts the cut-off frequency of the "Filter" knob. There are only two 1k resistors in the circuit. Modding these 1k's will either change the input over current protection of the op-amp or it will limit the amount of current going through the diodes. I believe your mod affects the diodes and would be interesting to hear with a 1k+ pot in it's place. Best mod I ever did - replace the OP07 with a TL071. I didn't think this would sound good at all, but it's amazing! The release/transients have very cool analog artifacts screaming in the back, but they sound clean and not noisy. Seems like it "lets go" way slower than the OP07, while simultaneously sounding "tighter" overall. The stock 30pf comp cap doesn't affect the OP07 in any way, but I switched it to 1pf for when I get a LM308. Not sure if this affects the 071 in any way, as that cap hits pin 1 which is the external input offset voltage adjustment pin. I would suggest anyone modding their RAT to recap the whole thing using Panasonic/Nichicon/Kemet etc electrolytics, film and MLCC's, as the caps and resistors it comes shipped with are trash. Source these parts only from Mouser or Digikey. The Cult of The RAT seems to be really missing out on Schottky diode mods. They don't seem to be a very popular mod option and they provide the most versatility with the RAT's filter. Way better than silicons. Does drum compression and transient shaping very well when using on an effects send. Just having a simple ON/ON switch to bypass the diodes and have pure op-amp clipping is like having two completely different pedals.. If you really want to hear the sonic characteristics of your RAT mods, you need to run signals like different drum loops and 808-sub bass hits to hear what these mods are actually capable of when switching through diode/op-amp selections.

[@rogergoldman1149]

very good video! thanks

[@RasCuban33]

Just did this mod, didn’t go the added bass route. Did one thing different though, I measured some new 1n4148s to find a lower forward voltage than what the stock ones were reading at. I’m totally happy with the results, it sounds very 80’s but can still Doom when pushed to the max. What is this mod called?

[@MatthewChapmanMusic]

To my knowledge it doesn’t have a name, but that’s a very interesting adaptation for sure! Post a video so I can check it out!!

[@profile_01]

It sounded good before it sounds good now

[@gergemall]

A very cool video

[@dominikkvocka103]

Good ideas for mods :) BTW whats that song in background?

[@MatthewChapmanMusic]

It’s called Hammerfist by a band I used to play guitar for called 3Eighty3. Glad you enjoyed it!

[@JMLRecording]

I want my gain “smoothemed” ❤

[@thefuneralparade]

Seems to me like except the thing that adds more gain that the rest of the mods take away the crazy sound that makes it doom.and great for super heavy sludgy fucked up broken sounds

[@zonkz6947]

You have a stroke or something, man?

[@o_o0_x914]

Can I send you my rat 2 to mod this for me?

[@MatthewChapmanMusic]

Sorry for the late reply! But yes! I will mod it for you. Send an email to [e-mail] and we'll discuss more!

[@00_ELECTRICWIZARD_00]

where did you say I can buy that LM308 mod kit chip?

[@tinroof4816]

Or buy the Donner Black Mouse for $25 and it has the LM308 already and sounds amazing.

[@thesimulations8900]

That is almost certainly a fake lm308 chip. Most online are fakes. Trues NS or Motorolla chips are hard to find. Especially in abundance to go into a production pedal.

[@tinroof4816]

@@thesimulations8900 It doesn't matter because the LM308 was never significant in the tone.

[@constantk8780]

​@@tinroof4816then why buy the black mouse specifically for an lm308?

[@roryadam]

@@tinroof4816 the lm308 was never significant to the tone?

[@EvilBlakey]

​@@roryadamNope, it really isn't.

[@stephend4674]

Background music kills this video

[@josecubanosantiago4724]

Idk I like the stock rat better

[@thefuneralparade]

Wow.i am impressed tho with th way it sounds by itself.deginaty does sound better.

[@roryadam]

instead of doing all this shit why not just run a compressor into the the rat and roll your guitars tone knob down?

[@오선조-i2y]

ㅏ

[@CC-fi3pp]

It looks worse

[@ampegloud]

I’m sorry sounds like crap you went to all that trouble to change all that shit that’s crazy

[@roryadam]

lmao, ahh shit thats funny, I had to scroll all the way to the bottom to finally find someone that agree'd with me

[@letch1529]

why mod something that is already perfect? if you want a different sound, buy a differnt pedal.

[@CC-fi3pp]

Because old RATs are better, they made the pedal worse to cut costs.

[@void_snw]

If everyone thought like that we'd never get new cool circuits