I did the 500k OCD Mod.

[larry rolando]

It fixed what i did not like about the pedal. It is exactly what i hoped the pedal would be when i bought it. If you like the hi fi thing the stock one has then leave it alone if you don't try it. I will warn you it is a bitch to do because of the gooping. The circuit board is gooped after the pedal is put together so you have to cut the goop from the side of the encloser. But worth the hour i spent doing it.

[Deaj]

I ordered a bunch of parts from Mouser this morning including the pot for this mod. I'm interested in hearing the difference and willing to put in the effort. Thanks for the report! :)

[Ed Reed]

what value is the stock pot?

[Gary Brennan]

Larry or anyone else,

Please someone post some comparison clips of the OCD mods. Thanks,

gb

[WailinGuy]

I ordered a bunch of parts from Mouser this morning including the pot for this mod.
Please post the Mouser part number for the particular 500K audio pot. Thanks!

I'm also interested in finding out what the stock pot value is.

[phoenix 7]

Larry,

Can you describe specifically how the mod affects the sound? I understand it provides more mids and smooths out the top end. Does the pedal sound fatter now for single note lines?

[larry rolando]

When i got the OCD i loved the amount of gain it had, i liked the way it felt under the fingers. I was hoping it was going to be a nice full body gain pedal, but it had what i would describe as a Aural exciter thing to it i could never get out. So yes it would be better for single coils the tone control is way more effective now noon is not to bright or dark, so you have something to work with.

[Ed Reed]

So you replaced the tone pot?

[Ed Reed]

Here's the dope

http://www.fulltone.com/ocd_questions.html

amazing what a guy can find on google huh?

[Ed Reed]

Could the same thing be acomplished by adding a resistor across the pot some way?

[dosmun]

Could the same thing be acomplished by adding a resistor across the pot some way?

If the stock pot is larger than 500K

[Straleno]

Yes, please, someone figure out if the same thing can be accomplished by adding a resistor across the pot, rather than wrenching it out!

[Ed Reed]

Just for fun I held some different value resistors across the lugs of the pot and it did change the tone simular to the description on Fulltone's sight BUT not having a correctly modded pedal to compare it to, I don't know how close it comes. I did not commit to solider.

[D.G.]

Yes, please, someone figure out if the same thing can be accomplished by adding a resistor across the pot, rather than wrenching it out!


Try this page http://www.projectguitar.com/tut/potm.htm

[Ed Reed]

When I put the resistor across the two outside lugs it didn't sound right, I got a better result on the middle and the outside lugs. Like I said though, I really don't know what I doing.

[NuSkoolTone]

Try this page http://www.projectguitar.com/tut/potm.htm

Good Site. So assuming the stock pot is 250k, How about a push-pull pot that engages resistors to change the volume pot value? That way you have both! Might be handy going form a les paul to a strat for instance...

[suhr_rodney]

Has anyone pulled the original volume pot from the circuit to measure the DC resistance? It's meaningless, but in the circuit the pot in mine measures around 88k ohms. Just trying to avoid tearing apart the pedal if I don't have to.

Also, I'd love to know sources and part numbers for the 500k ohm pot. Too bad Fulltone does not provide more info on this topic.

[dosmun]

If the stock pot value is smaller than 500k you won't be able to add a resistor. To get to 500K you would have to add a resistor in series with the pot and that would eliminate some of the sweep of the pot.

[RMcFarland]

I would be afraid of losing the beautiful upper register harmonic overtone I am getting....If it is indeed "smoothing out the top end" it is probably cutting treble. Why not just roll back the tone knob?

Off-topic, this may be the best suited overdrive for a telecaster....it retains all of the bite and bass for some healthy distorted twang and the treble stays intact with great harmonics when doing steel bends.......INCREDIBLE PEDAL........

[suhr_rodney]

The stock part is 100k. Can someone please post the part number and/or a source for the 500k part?

[gtrnstuff]

I'm looking for the exact replacement, too. Mine has the goop from the jacks all the way around the pots. So I won't be getting the board out. After about 1.5 hours, I did manage to carve away a clean line around the vol pot, so if I snip the leads and use needle nose to unscrew the internal lock nut, I can see a way to get the pots traded out.
I've emailed Fulltone to ask for a source--we'll see. Sometimes he'll just send parts gratis.
At least the pedal still works after all my hacking.

[suhr_rodney]

Why is it like pulling teeth to get Fulltone to reveal the part # for the 500k part? It's not like I'm asking for a free replacement - I just want to know where I can buy the freakin' part. Sort of like buying the first year of a new car, it did not pay off to be first in line for the OCD. Mine is about to have a journey to the bottom of the nearest lake.

[gtrnstuff]

Hi Suhr Rodney. If your board isn't too gooped to pull it out, a standard small pot would fit between the board and the case. I was all set to do it that way, then I found out just how tough that stuff is. JB Weld?
Have you looked at Fulltone's "OCD mod 2" picture yet? He's using a lot less gunk these days, if that's a production piece. I can't even clip out that cap without fear of lifting a PCB trace.

[jlagrassa]

Although its more expensive way of having the modded version I might just buy one of the newer ones just to have it, Personally I like the one I have now as it already sounds great with my Fender amps.

On a big sound stage that added Bass and treble helps keep the sound full and clear, I'm assuming the mod is not that dramatic but just enough to please the people looking for the changes requested.

[jlagrassa]

Hi Suhr Rodney. If your board isn't too gooped to pull it out, a standard small pot would fit between the board and the case. I was all set to do it that way, then I found out just how tough that stuff is. JB Weld?
Have you looked at Fulltone's "OCD mod 2" picture yet? He's using a lot less gunk these days, if that's a production piece. I can't even clip out that cap without fear of lifting a PCB trace.

Just checked that 2nd mod out, Didnt know about that one looks like an easier task than the pot replacement!

[n8b]

I don't own an OCD, but from the pic on the mods page, it looks like the pots are 16mm pc mount. Do a search for 313-1530-500K at mouser.com and open up the catalog page. See if one of the pots at the top of the page matches up. Also, if someone knows whether the pot is audio or linear taper, that would help.

[gtrnstuff]

Yeah, those would work IF you can get the PCB out of the case. Mine is gooped from edge to edge, from pots to jacks. I haven't found one with the long 1" shaft, with the threaded sleeve (estimating) 3/4" like the original. I have an email out to Don Butler for a price quote for the whole job--we'll see.

[suhr_rodney]

The mod calls for a 500k audio taper pot. Here are some pics of the original pot and the OCD with the pot removed. It took a little time and care to get the original pot out, but it is not a difficult job. Just be careful as there is a capacitor and a couple of resistors that are fairly close. Go slow and it's a piece of cake.

http://i10.photobucket.com/albums/a137/rclemmer/OCD/DSCN4010.jpg

http://i10.photobucket.com/albums/a137/rclemmer/OCD/DSCN4011.jpg

[gtrnstuff]

Wow, yours sure is cleaner than mine. I had to cut goop almost all the way around that pot, except for where the leads exit. Like cutting a fossil out of bedrock. If I had a dig camera, I'd post it. Now the real question, have you found an exact replacement or do you still have to lift the board to put in a short shaft pot?

[Deaj]

I've ordered and received two different pots and neither were a proper fit. Does anyone have a source and part number for the 500K audio taper replacement pot?

Thanks!

[jdps150]

There's someone here *who shall remain nameless for now* who found a magic chemical to remove the "goop".

[Ed Reed]

In all honesty, it looks like a guy would be better off selling his old OCD on ebay and just buying a new one. I'm sure if you sent the thing to Don Butler it's going to cost $50.00 anyway, if he can do for that. I'm also sure a pedal modded by just anyone will lose it's resale value too. This looks like a lose/lose deal to me. Just have to decide what lose is the least.

[gtrnstuff]

Let's make thread thread a little longer, shall we? For me, it became "I'm not going to let this thing beat me". So another couple of hours with a razor saw and chisel and my board is free. Obsessive-compulsive, indeed. Now to find a pot that fits a 7mm hole. I could drill, but I don't want to chip the paint where it's visible.

I'd love to know what dissolves that stuff, and leaves the components and PCB intact. Bet that's a slimy mess, and good to breathe, too. It's not peanut butter, is it??? Nail polish remover???

For me, I don't want to sell it before I'm convinced the new version is really better, and I didn't want two of these things.

[Lefty]

Keep in mind, when the market is littered with the new version and ones that people have modded...the original ones will be worth big $$, and will sound better.:eek::jo:)

[Ed Reed]

Obsessive-compulsive, indeed.



The turth has been spoken.

[RMcFarland]

they already do sound better........

[gtrnstuff]

>"Keep in mind, when the market is littered with the new version and ones that people have modded...the original ones will be worth big $$, and will sound better."

Yeah, and Mike will build a custom shop version with both pots, kind of like the "vintage/flat mid" Fulldrive.
Hey, he says right on his site everything is subject to change, depending on what sounds good to him that day.
I don't really mind playing along, he makes great stuff, he's sent me switches when they failed prematurely, and I'd rather tweak than trade.

[Gary Brennan]

Don Butler quoted me $20 for the OCD mod. Then add shipping. I'm still hoping for A/B clips before deciding.

gb

[suhr_rodney]

If you really want to keep the existing sound, it should be simple enough do the mod to a 500k pot and add a switch (push-pull or mini-toggle depending upon space constraints) to put a 125k ohm resistor in parallel with the pot. (Note: 125k is the theoretical value. In practice you'd likely use the closest standard value depending upon the tolerance resistor you are using.)

[Deaj]

I just finished installing a 500K audio taper Volume pot in my OCD. I used Mouser part # 31JA505 and mounted it under the circuit board just as pictured in jlagrassa's post above. The mod went smoothly and I like the change! It's not better or worse than stock - just different. I'll comment more once I've had some time to play with it.

[jlagrassa]

Just got back from practice and used the OCD with the mod#2 installed and I thought the pedal sounded real good.............and this is with my 65 DRRI. Still had a nice crunchy ryhthm and fat lead tone but with less bass but there is still a nice low end still there!

I'm sure it will sound even better through my 59 Bassman RI, Anyway if your looking for bass reduction try the cap change in the OCD mod#2 I think it is worth it!
************************************************** ******************
Update, Decided to keep it stock so I put back the original value cap!

[gtrnstuff]

Jlagrassa said
>"Anyway if your looking for bass reduction try the cap change in the OCD mod#2 I think it is worth it!"

How big was the goop glob on your cap? Did it come off the board easily for you? Mine spreads over the PCB, and the way that stuff stuck to the painted metal I'm still not sure I can get it clipped off enough without damaging the traces. Thanks in advance.

[Deaj]

Well, after playing with the modded OCD for a while I decided to return it to stock. I'm using this pedal for rhythm tones and the stock volume pot just seems to work better for this purpose in my rig. If I were going to use the OCD for lead playing I think the 500K volume pot would be a better choice - sounds a touch smoother with more mids. I like the 'rude' character of the stock 100K pot better for rhythm work though.

[suhr_rodney]

I have a 500k pot on order with Don Butler (aka "Toneman") and will report back once the new part is installed.

[guitarchris]

I like the bass response of the OCD. I just want some more mids. Is there a mod for more mids that doesn't kill the bass and highs??

[gtrnstuff]

OK, the Mouser part # 31JA505 (Thanks for posting, Deaj!!) "16mm" Alpha pot just dropped right in the 7mm hole. Gotta say, I really like the 500k vol. So far don't miss the scooped thing at all, it doesn't seem bass-shy, and the top end is Much Nicer. Like Larry said when he kicked this thread off, this is what I was hoping this pedal would be.

[dosmun]

For the guys that have installed the 500k pot it would be easy to have a switchable resistor to toggle between the original sound and the new sound. A 125K resistor across the outside lugs of the pot would get you down to 100K again.

[paulg]

DG: Thanks, adding a resistor across the pot would seem a lot easier to do (and remove if it dosen't work as expected). Do you know the stock value pot in the OCD?

[gtrnstuff]

PaulG:
See page one of this thread.

[Phil Harmoneeek]

So if I use "OCD Mod#2" (insert .047 cap) from the Fulltone site & then want to put it back to stock again, what is the stock value of the original cap.

Thanks Randall

[Phil Harmoneeek]

Ya ... everyone will need to know when they decide to go ... back!!! :NUTS

Randall

[Deaj]

So if I use "OCD Mod#2" (insert .047 cap) from the Fulltone site & then want to put it back to stock again, what is the stock value of the original cap.

Thanks Randall

I just measured the stock cap. It's a .1

[Deaj]

I've gone back to the 500K Volume pot mod. While I like the 'rude' character of the stock 100K pot I missed the fat mids and sweeter highs as soon as I returned the pedal to stock. Since I had the pedal open I decided to go ahead and try mod #2. I measured the stock cap first (.1) and then carefully cut the goop away and replaced it with the suggested .047. I'll be damned if these two mods don't turn the OCD into one of the best OD pedals I've ever plugged into! The stock bass response is amazing, true, but almost to a fault to my ears. The .047 cap does reduce the bass response a bit but there's still a ton of low end there and it seems more balanced now. HOLY CRAP! This thing sounds great!

BTW: I bought my OCD used and someone had already been inside of it with a soldering iron. I try to resist the urge to wave my soldering iron around inside expensive electronic gadgets until I've determined that I'm keeping said gadget forever (I haven't reached that point with my OCD but I'm real close after tonight). This OCD had already been modded and returned to stock and so no value is lost tinkering. :)

Update: I've been swapping between the .047 and the stock .1 cap and, again, I like both. I just returned it to stock for now and I'll play with it for a couple of days. This is fun! :)

[jmcerlain]

0h man, why did I have to read this thread? I was perfectly happy with my OCD, now this. Will it ever end???:FM

[jlagrassa]

Deaj, thanks for measuring that cap!

So do you definitely prefer the 500k pot over the 100k? I will probably order one soon!

[Deaj]

Deaj, thanks for measuring that cap!

So do you definitely prefer the 500k pot over the 100k? I will probably order one soon!

I do - right now. :D The stock 100K pot also sounds great to me but I'm really diggin' the sweeter highs and increased mids with the 500K pot.

[ASATClassic]

Is the mod subtle or more dramatic?

[gtrnstuff]

Dramatic IMO
See Larry's posts on page one.

[Deaj]

Yeah, it's a fairly dramatic change.

[Uchison]

0h man, why did I have to read this thread? I was perfectly happy with my OCD, now this. Will it ever end???:FM

+1 mine

[suhr_rodney]

Deaj, which cap did you end up with? I'm eager for my 500k pot to arrive and will likely do the cap mod at the same time I install the pot.

[Deaj]

Deaj, which cap did you end up with? I'm eager for my 500k pot to arrive and will likely do the cap mod at the same time I install the pot.

Right now I'm using the stock .1 cap. I'll likely give the .047 another shake in a week or so. Though both mods sound great together I'd suggest going one mod at a time. This way the effect of one is not clouded by the other.

[suhr_rodney]

Wow! I did the 500k mod to my OCD today and used it at practice tonight. This change made an unbelieveable difference in the usefulness of the OCD in my rig. I played primarily through my Route 66 and my tone was very fat. The characteristics of the OCD that I loved from before are still there, but the warmer and slightly more pronounced mids make all the difference. I highly recommend this mod for all but those seeking the highly scooped mids the 100k pot produces.

[Deaj]

Wow! I did the 500k mod to my OCD today and used it at practice tonight. This change made an unbelieveable difference in the usefulness of the OCD in my rig. I played primarily through my Route 66 and my tone was very fat. The characteristics of the OCD that I loved from before are still there, but the warmer and slightly more pronounced mids make all the difference. I highly recommend this mod for all but those seeking the highly scooped mids the 100k pot produces.

Glad to hear it! I'm really diggin' the change too. I have found a wider range of tones with the 500K pot. Right now I have it set up using LP mode, gain at 12 o'clock, and tone at 1 o'clock. It's really a great OD pedal!

[el34power]

0h man, why did I have to read this thread? I was perfectly happy with my OCD, now this. Will it ever end???:FM

LMFAO:jo

I know what you mean :FM

[Straleno]

I've just done the 500k mod, and I'm very happy with the results. As others have said, it's what I've wanted the pedal to be all along. Before, the LP setting wasn't really usable for me (Tele & Allen Old Flame), but now it sounds beautiful, very sensitive and amp-like. And the HP setting adds a nice bite. I'd definitely recommend it. My only (minor) complaint is that with the pot installed between the board and the casing, the pot is now too long, so the knob sticks up a bit, and there aren't enough threads on the pot shaft to pad it down with extra washers. Oh well...

[WailinGuy]

My only (minor) complaint is that with the pot installed between the board and the casing, the pot is now too long, so the knob sticks up a bit, and there aren't enough threads on the pot shaft to pad it down with extra washers. Small Bear Electronics carries 16mm Alpha pots with shorter shafts. Mouser doesn't carry these for some reason.

I have a different problem, and I'm wondering if anybody else has run into this:

So far, I haven't been able to replace the Volume pot in my OCD because there is so much goop to cut through before the circuit board can be removed. (I'm wondering if my particular OCD has more than the usual amount of goop.) There's goop between the circuit board and the both sides of the enclosure (it's especially bad on one side) and there's also goop between the circuit board and the input & output jacks. There's also a fair amount of goop surrounding the pot itself. I found it to be very slow going using an X-acto knife. The goop is so hard and so tough that it resists scraping, even by a very sharp blade. Maybe some type of miniature saw blade would work better?

I'm curious about what other guys used to cut through the goop and how long it took. (Was it a day-long project for some?) I've considered just sending it to Don Butler, but he hasn't been very responsive to my email inquiries. I don't mind spending the $20, but the idea of being without my OCD for several weeks or more is bugging me.

I'd appreciate any and all suggestions.

[Third Stone]

I think a dremel tool would be perfect. It's similiar to a drill with many different blade attachments. Do a search on Google if you are not familiar with Dremel.

[Straleno]

Mine was not very goopy at all, luckily... the only spot I had to worry about was a few millimeters of epoxy attaching the board to the input jack, and I didn't even need to cut it, it just snapped off pretty easily. What was hard on mine was that one of the wires attaching the switch (I think) to the board ran tautly under the output jack, giving me very little leeway to pull the board up to fit the pot in. I don't know if they're all like this.
The whole job took me maybe an hour and change.

[gtrnstuff]

In case you missed my post above, I did mine by hand in about 3 hours total(!!!). Avoided the Dremel since I didn't know what I was cutting into, the goop was so deep. Trash a component or a PCB trace, buy a new pedal. Chisel, razor saw, and box cutter/ Exacto knife. And I loosened the switch, too, to get some slack in the leads.

[WailinGuy]

I own a varaible speed Dremel. But there's no way I would use it in this application. It's a very powerful tool, but one little slip, and you can destroy something before you even know it. Dremel cutting wheels can create a lot of heat, smoke, and dust. Too risky for me.

I guess I need to get some type of low-profile razor saw, to use along with my X-acto knives. Even still, I can easily imagine spending 3+ hours alone (more like 5+) cutting away the goop carefully without ruining the PCB or the metal enclosure.

[jdps150]

2 nites ago I started getting the goop off of the board/case joint using a utility knife.
Wound up breaking a lead on one of the vertical resistors. Thankfully, it did not break @ the body so it was an ez fix.

Thought about the Dremel, but, now...

[Liquid Sunshine]

I decided to buy a new OCD w/ the 500k and have the old one to compare b4 I ebay it. There is a very big difference between the 2. The mids jump out huge compared to the original. The hi fi sound went away. The sound I hated when I went up on the neck soloing. Went from natural to wierd sounding un-natural overdrive.

I run the tone now @ 12:00 and doesn't have that high-beam bright glare to it. The LP mode b4 was completely transparent until the gain was up enough to hear that hi fi sound. Now you hear the mids bloom right thru. Still transparent. It still has that really gonna blow the doors down when you open it up to 8 - 9 on the volume on your guitar. There is alot of power and dynamics with this pedal between 6 - 8 on your guitar volume. Much better for leads. You can get a more buttery sound I feel with the 500K in there w/ the tone rolled back to 11:00. I played the old 100K and it was raspy with the gain in comparision.

I can't tell which knobs I like better...lol. My new one has the black knobs while my old has the cream ones. Might switch 'em b4 I ebay it..lol.

[WailinGuy]

Warning to those of you with heavily gooped OCDs (such as mine): doing the 500K mod yourself is not for the faint of heart!! :eek:

I finally did complete the 500K pot mod on my OCD last night. It easily took 5 or 6 hours (over several evenings) and a bunch of X-acto hobby knife blades to cut through all of the goop bonding the circuit board to the sides of the box and the jacks, as well as the thick layer of goop going halfway around the volume pot. (A can of compressed air to help remove the "goop dust" was a big help here.) After I was able to free the circuit board and remove the original pot, the rest of the job was cake. I mounted the Alpha 500K audio pot (which measured 471K) to the enclosure and connected the pot to the circuit board with three short pieces of #20 tinned buss wire. The pot has the correct shaft length, so after the mod was completed, my OCD from the outside looks like nothing ever happened to it.

I agree with the others who have modded their OCDs or bought one of the new ones that come stock with the 500K pot - it is definitely a noticeable improvement. Before, I was always going back and forth between HP and LP modes. LP sounded smoother and more refined, but it was too scooped; whille HP had too much of an exaggerated upper midrange peak for my ears. Now, the LP mode seems a lot more useable. It's fatter and richer sounding.

I didn't notice as big a difference in the range of the tone control as other did. I still need to keep it well below noon. Somewhere between 10:00 and 11:00 is about it for LP mode. By the way, my OCD still has the mod in place that reduces the output cap from 2.2uF to 1.0uF (the "original" bass reduction mod which I think is now superceded by "mod #2", which reduces the value of a cap in the pre-gain part of the circuit from .1uF to .047 uF). There's still plenty of bass, so I've kept the output cap at 1.0uF. I might try going back to 2.2uF just to see what that does now in combination with the higher pot value.

I also did mod #2. (Actually I did this one first, before the pot change mod.) Although I like how it makes the OD tone smoother, I noticed that it also made the tone brighter and noticeably reduced the gain - I needed to turn up the gain knob more than before in order to achieve the same level of overdrive. Has anyone else noticed this? Anyway, I went back to the .1uF cap.

I'm definitely sticking with the 500KA pot, however. I an't wait to see how my OCD does at stage volume.

[Deaj]

I've had the 500K audio taper volume pot installed for a couple of weeks now and I much prefer it over the stock part. I decided to give mod #2 another go hoping to tame the low end a bit. The .047uf cap does reduce the available gain but there's still plenty of gain on tap. The midrange is also a touch sweeter. I really like what this mod does for the OCD - it has a singing quality now. Still a fantastic rhythm OD and now a great lead OD as well! I'm glad this information was made available. It turned a good OD pedal into a great one!

[WailinGuy]

Deaj, since my OCD is no longer in "original condition" anyway, I'm considering maybe adding a mini toggle switch on the side that would allow me to easily switch between the .1 and .047 caps. Maybe I'd name the two positions "crunch" and "sing". I have a feeling the .047 cap really wants the output cap to have the stock 2.2uF value to prevent the tone from getting too thin.

[Deaj]

Deaj, since my OCD is no longer in "original condition" anyway, I'm considering maybe adding a mini toggle switch on the side that would allow me to easily switch between the .1 and .047 caps. Maybe I'd name the two positions "crunch" and "sing". I have a feeling the .047 cap really wants the output cap to have the stock 2.2uF value to prevent the tone from getting too thin.

That's quite possible. I find the tone with the .047uF cap and the 500K pot to be pretty thick. The switch is a cool idea!

[jlearman]

For the guys that have installed the 500k pot it would be easy to have a switchable resistor to toggle between the original sound and the new sound. A 125K resistor across the outside lugs of the pot would get you down to 100K again.

How would you do this to a PC board mounted pot? Sorry if that's a stupid question, but I haven't done anything like this before.

Thanks!
Joe

[Baby Evil]

Anyone know where to get the right pot in Europe? I've mailed a couple of suppliers, but they don't seem to have pcb mounted pots with long shafts.

thanks,

Jan

[gtrnstuff]

Well, the replacement isn't exact. The pictures that were on Fulltone were of a short shaft pot using wires or resistor leads to jump from the pot terminals to the PCB. As long as you get the right diameter for the hole, 7mm IIRC, you're good.

[dosmun]

How would you do this to a PC board mounted pot? Sorry if that's a stupid question, but I haven't done anything like this before.

Thanks!
Joe

Just solder it to the outside lugs on the bottom of the PC board.

[Entztrix]

have any of you tweeekers came up with a schematic yet?

[Entztrix]

ok!
My schematic question seemed to quiet this thread.....
Anyway this is a very interesting topic....
has anyone removed all the goop
so there is a cap mod, a pot mod, and a resistor across the pot mod....
has anybody set theirs up wtth a toggle switch or push/pull pot
so they have a frankenstein obsessive compulsive drive

[jdps150]

Schem? You just swap a 100K pot for a 500K, &/or one cap for another.
Pretty straightforward.

After 3 or 4 attempts I finally liberated my board. Might try the 500K tonite. Gotta dig up a cap.

[Entztrix]

i wanna schematic to build my own

why would mike put the goop on there....obviously to promote cloning haha

[skiraly017]

...the OCD is based on a RAT pedal. The RAT schematic can be found in a couple of places.

[WailinGuy]

BTW, for the "OCD Mod #2" (described on the Fulltone web site), I found that replacing the stock 0.1uF cap with a .068uF (instead of a .047uF as per the mod instructions) is probably the better choice. The .047 thinned things out a little too much for my ears. The .068 seems to be a good compromise between the overly bassy (and splatty) tone of the 0.1 cap and the clear and smooth, but somewhat thin tone of the .047.

BTW, I used a cheap-o "greenie" 100V polyester .068 cap, available from Mouser. I had also experimented with a .082, but decided after playing around with it for a while that there was still too much bass going into the clipping circuit. For those who are interested in experimenting, I recommend getting caps in all three values (.047, .068, and .082) and letting your own ears decide which sounds best.

[WailinGuy]

Supposedly...
...the OCD is based on a RAT pedal. The RAT schematic can be found in a couple of places.

I don't know where you might have heard this, but I would question it. First of all, the RAT uses clipping diodes, and Mike Fuller claims that the OCD doesn't used diodes to clip the signal (which is why it is so much more dynamic than most overdrive pedals.) Also, the OCD's tone control reacts nothing like the RAT's filter knob (even if you ignore the fact that the RAT's filter knob works in reverse - turning it clockwise filters OUT high frequencies).

Perhaps there's some PART of the OCD circuit that is lifted from a RAT, but I don't think the RAT schematic would get any would-be OCD cloner very far.

Even if I somehow knew details of the OCD circuit design (and I certainly don't) , I would not discuss it here or anywhere else. Since this pedal is a recent product and it's circuit is not in the "public domain" (as is the case with TS-808 or Fuzz Face), doing this would seriously violate my sense of integrity. And this would have nothing to do with any feelings I may have, positive or negative, about Mike Fuller.

[Ed Reed]

Mine is hoplessly epoxied in, I'd end up destroying it to get it out. I did the mod #2 and then I tried wiring in a 500K audio in parallel with the stock 100K, I'd suppose this makes a 400 or a 600K load (?) anyway, it smoothed the pedal out, as in reduced the highs and increased the mids. I now run the tone at 9:00 and the pedal sounds better than it did. To me anyway.

I opened the 500K up 3/4 the way and still use the stock volume to adjust (less volume than before this way) and put the 500 in the battery compartment. I use a power supply.

[Uchison]

Could somebody post clips?? I'm really curious to hear the difference.
Thx.

[archtopjazz]

Does ANYBODY like the original OCD over the new OCD?

[jdps150]

I'll let ya know after the weekend. :)

[dewman]

Anyone with B4 and after clips with the mod?

Do you need to do mod #2 or does it make a big difference paired with the 500k pot?

[Entztrix]

i should of recorded my practice session today....here's the story

I am the lead guitar player of the hermans(www.myspace.com/thehermans (http://www.myspace.com/thehermans))
my setup is

Ibanez semi-hollowbody->TBypass Wah->fulltone 69 fuzz->OCD->TS-9->analogman bicomp->boss sd-1/808/silver->boss ce-2(japanese)->line6 dl4->modded carvin xv112 oak

After i got my ocd my rhythm guitarist/singer got huge pedal envy as he goes fender tornado straight to fender deville. We plugged the OCD into his axe and he loved the tone, so I told him where to purchase one. Of course i have an old one and he got a new one. Mine fits his sound way better....but I purchased mine for a rhythm pedal so i aint tradin him. I had them plugged side by side for like a hour and the difference is huge. I got it as a replacement for my boss ds-1 and it fit the bill perfect. The new new one doesn't really do the same thing at all(but is still super sweet!)....it sound much much middy..er.
No matter what i did i could not come close to matching their sounds. but holyfu*kness! they sound awesome cascading! Crazy tone and sick inner modulations during double stops. I am now on a quest to find an old OCD somewhere...anyone want to ditch one? I hope to find an old one for my bandmate so i can have his new one because cascading them is truely a thing of beauty. Anyways I hope mike makes a double d with both models and a toggle for the capacitor mod. That would be the real ultimate obsessive compulsive distortion.
Peace

RUOCD?

[stomper]

Could somebody post clips?? I'm really curious to hear the difference.
Thx.

Follow this link for a clip of an earlier OCD. I have number 3906 and modded it to 500K and am using a .068 capacitor.
enjoy, stomper

http://translate.google.com/translate?hl=en&sl=de&u=http://www.dietside.de/OVERDRIVETEST.htm&prev=/search%3Fq%3Dbaldringer%2Bdual%2Bdrive%26hl%3Den%2 6lr%3D

[Uchison]

Follow this link for a clip of an earlier OCD. I have number 3906 and modded it to 500K and am using a .068 capacitor.
enjoy, stomper

http://translate.google.com/translate?hl=en&sl=de&u=http://www.dietside.de/OVERDRIVETEST.htm&prev=/search%3Fq%3Dbaldringer%2Bdual%2Bdrive%26hl%3Den%2 6lr%3D

Yhx, I only wish that you wopuld have a side by side clip. Anybody else?
This sounds nice, but I'm not sure how much different thsi sounds compared to mine.

[Entztrix]

Does ANYBODY like the original OCD over the new OCD?

my vote is for the original. It sounds more like what i thought the ocd would sound like before i got it. The new one seems to give it tubescreamerish overtones on my amp.

[jdps150]

Just put the original 100K pot back in.
It was too polite.
Might try the cap at a later date.

[Entztrix]

i have all my gear home from my practice space. I will record some comparison clips tomorrow.....i'm a little too beer buzzzed now, but promise on some clips.

[Entztrix]

yo everyone

I recorded a track of me playing both ocd's side by side.

http://www.myspace.com/analogatron

go to my myspace and download track ocd 1 off my musicplayer. For some reason my page will not just play it like its suppose to, but i think its downloadable. The track desert island is an old model ocd as well if your interested in hearing it in rhythm and lead action.

anyway the ocd 1 track goes like this

one simple rhythm idea with an older ocd, then i pause and do the same riff with a new one.
then i do a lead idea with the old one, pause, and do a lead with the new pedal.

both pedals are in lp mode with all the knobs at 12 oclock

if anyone's interested i will do some more on sunday.

peace:JAM

[Entztrix]

sorry guys this link might be easier myspace sorta sucks

http://www.soundclick.com/bands/pagemusic.cfm?bandID=477187

[Baby Evil]

Thanks for that comparison. Mind doing one with HP mode?

I was thinking of doing the mod, but I'm having doubts now. I definitely prefer the old model for rhythms; for more mids in my leads the Barber Ltd as boost works just fine.
It's just that with my strat, I've got to keep the tone knob under 11'0, or it's icepick time.

Jan

[Uchison]

yo everyone

I recorded a track of me playing both ocd's side by side.

http://www.myspace.com/analogatron

go to my myspace and download track ocd 1 off my musicplayer. For some reason my page will not just play it like its suppose to, but i think its downloadable. The track desert island is an old model ocd as well if your interested in hearing it in rhythm and lead action.

anyway the ocd 1 track goes like this

one simple rhythm idea with an older ocd, then i pause and do the same riff with a new one.
then i do a lead idea with the old one, pause, and do a lead with the new pedal.

both pedals are in lp mode with all the knobs at 12 oclock

if anyone's interested i will do some more on sunday.

peace:JAM

Many thx for this. Noe it's easier to hear the differences. What guitar/amp are you playing with? Just to make the whole picture more complete.

[Marty McFly]

Thanks for recording and posting the clips. The mod does sound a bit smoother and more buttery. I like it!

[Entztrix]

will do some hp clips after my girlfriend leaves for work today.

I am just using my cheapo practice line 6 with my girlfriends mexi strat. Going direct into my soundcard. My ibanez les paulish guitar, tube amp, and mics are all still at my practice space.

[dewman]

That might make a difference. I finished the mod last night (and it still works), I left the 0.1 cap in place (mod#2) so we're cranking it up today...off the bat, way different tonal changes at bedroom volumes (cant wake the wife or kids at 1 am, not good. Anyway, more soon.

[dewman]

ok...played the new OCD w/ mod #1 and it is absolutely the best now. With my Germino Club 40, there was a horrible scooped mids sound when using a gibson 335...gone...the strat and gibson sounded absolutely great. Thicker mids, no 30,000Hz hi fi sound. Dial it up in either mode and its great. It used to be for lack of a better work weird sounding when the gain was maxed up, but fine for rhythms. Now with the gain dimed you can get a singing tone which still is dynamic and has clarity. Wow what a difference. I wish I has a recording setup to let others hear what I am hearing. The Germino is a Marshall 1967 JTM50 clone, but with some modernizations. SO as you would imagine the sound with humbuckers is sweet when overdriven but never totally clean at reasonable volumes for playing. Gibson sounds over the top with the OCD engaged, especially with controls all near 12 on the OCD. It smooths out the raspiness of the 335 significantly, and gives those singing qualities to the guitar. The leads on the strat are fuller and it is an amazing improvement. I am lucky to have a loud clean Ampeg VT-40 for comparison. EQed abit like a fat fender twin (scooped mids) the now modded OCD sounds great with both guitars with the ampeg. This amp was more forgiving than the Germino. With the Ampeg, I get the bluesiness of the 335 shining through on the neck pickup with the OCD engaged. Remarkable difference this simple mod makes. I like it the way it is now and probably will not do the mod #2 unless someone can give me a good description of how it will change the sound. I like it fat , and the strat through the VT40 at playing volumes is all blues. Fat fat fat with breakup when you bang it hard. Cranked up the drive knob and again was rewarded with a more smooth and mid rich very usable tone which was a bit more clear than a tubescreamer but had pronounced mods which sound good, depending on where the tone and gain were set w/ volume. So I am happy and now see what people are talking about. Didnt get it at all before, got the metallica scooped mids all over the place and could not deal. Thanks for saving this pedal from Ebay. If anyone can comment more on the mod #2 and its effect on performing mod#1 that would be great. I am afraid if I lower the cap value and reduce mids then I'll be heading more towards the old OCD territory and I aint crazy about that...anyone want to buy a 100k pot...????

[tedm]

does anyone like v3 over v2 ? I like V2 a lot.

Does ANYBODY like the original OCD over the new OCD?

[Deaj]

does anyone like v3 over v2 ? I like V2 a lot.

I'm with you. The ver.2 OCD sounds fantastic!