Modify Your Wah Pedal

After making my talk box I started surfing the web for other guitar related things I could do myself. I found loads of info on the Dunlop GCB-95 wah pedal. This Instructable will walk you through all of the modifications I made to my wah pedal...

*True Bypass Mod
*Volume Boost Mod
*Wah-Volume Pedal Mod
*Vocal Mod
*Midrange Mod

After having completed all of these mod and a few others I recommend doing them one at a time and testing in between mods so if you don't like something, you can easily reverse it.

Your gonna need some basic soldering tools...
-good soldering iron (mines a Weller WESD51D I got for christmas)
-solder
-wire cutter/stripper
-helping hand (a must!!)

also the to wire anything to the board itself you will need 24AWG wire

Step 1 Research

I think this is a big step in all of my projects. You don't want to just jump in without input from multiple sources. A few of the site that helped me were...

http://homepage.ntlworld.com/s.castledine/greenfuz/wah.html
http://www.stinkfoot.se/andreas/diy/mods/dunlop.htm
http://www.guitarzone.com/forum/index.php?showtopic=176864
http://www.geofex.com/- click "FX Technology
-Technology of the..." in the upper left
http://www.geocities.com/overdrivespider/tb.htm
http://www.geocities.com/j4_student/schematics.htm

These are some pictures I found useful...

Comments

[ArtXander]

Hi! I haven't understand how to wire the pot. I must connect the pot where there is the 33k resitor? 1&2 lug together to a side and 3 to the other?

[angelofdeth68]

Great instructable. thanks.

[jphoton]

hi guys, lifting the ground of the cap in question will indeed kill MOST of the wah effect, but it will not make it a true volume pedal...it will make it a tone pedal for all intents and purposes. it will kinda work on volume...sort of...but it won't be a true volume pedal. tried it on my old gcb95 long ago, was too lazy to un-do it...it can be interesting, but don't be disappointed when it doesn't work the way you'll probably envision. good luck mate!

[Jezrael]

Wich resistor do you recommend to replace the 68k resistor? or, wich value did you use? Greetings

[thewizard42]

Do you mean spdt? or does it have to be double pole, because i do not see why you would need the second pole

[overdrive555]

hi boys, why u dont use a trimmer to replace 1.5resistor?

[butthead95]

Buy the Crybaby From Hell it has most of this stuff inclyuding a five selection knob for dif ranges

[DrXavierAJones]

Yeah, its also 200 dollars.

[alenchence]

Hi!
I have a problem:when I click on the link for the installation of a new switch,it says the instruction is no longer available,so please help me out!I would like to do this mod,tone sucking is driving me crazy!
Tnx

[mesaiphoneguy]

 will this also work on a 535Q crybaby wah pedal?

[stupidityisagift]

hey, can you mod it for volume another way besides the capacitor? i have a snarling dog wah and want to mod it for voume, and i doubt the capacitor switch will work the same

[rcrane]

Hey, I am stuck. I have a green board like the one above and it is labeled 'E". I did the following: Removed old switch Removed the buffer components replaced the 33k with a 68k replaced the 1k5 with a 2.8k installed a 3PDT switch My problem is that I only have four wires to attach to the switch: 2 blue 1green 1purple I dont see any pictures showing the installation of the 3PDT usingmy board. Do I need to install wires where I removed the buffer and solder that to the switch? I don't know how to configure the wires on the switch. Help!

[James Haskin]

I added a picture from step 3 to step 2. My pedal is also a green E type board but all of dunlops circuits are so similar (except fro maybe Dimebag's Wahs from hell) that the wires from the top of the board to the pot and switch are the same.

Using switch diagram 5 as a reference tool.
connect...
Both PCB and Pot Blue to 7
PCB Purple to 8
PCB Green to 9 as well as a jumper to 1
Connect the transistor jumper to 2
and the resistor jumper to 3

[rcrane]

Got it! Sounds much better. Thanks for your help. I am still experimenting with the pot range. But MUCH more vocal and quiet! thanks again

[rcrane]

James, Thanks for the quick response! So that explains how to wire the existing wires. I only changed two resistors and changed the switch, so I will attach the wires like you said and then I just need to add two wires to the area that I removed the buffer and wire them to 3? rcrane

[abehughesmusic]

Hey I just did the Wah/Wolume mod, (that's the only mod I did). Admitably I didn't do a great soldering on the board, but all the contacts seem to be solid and the pedal basically does as it's supposed to. The problem I'm having is that in the Volume setting in the pedal doesn't get all the way quiet in the far back position. Did I miss something? This was my first attempt to mod a pedal and except for that one thing, which I'm really not going to loose sleep over, it seems to be working and not giving me any particular trouble. Thanks for this instructable. After I do some more work, I'm going to try a keely mod I found for my tube screamer, and (fingers crossed), try doing the seeing eye/ ultra mod for my DS-1. Thanks again.

[James Haskin]

When you move the pedal your actually turning that big greasy pot. the range of the pedal is shorter than the range of the pot. Basically, when engaged, the pot is never fully on or off. Look up how to calibrate a wah pedal and you'll see what I mean. The fact that it doesn't go dead silent doesn't bother me.

[somerockenguy]

could you elaborate on this i would love to do this mod (wah-volume mod) but i only partly get how to do it. you think you could do an instructable on just that or point me to a web site that has a how to on it?

[James Haskin]

Ok so here the deal, sometimes people say they have "broken" wah pedals. They will say that its only changing the volume. Well that happens when this capacitor blows/dies/goes bad. So what I did was desoldered it from the board and hooked up two wires to it (pic1). Then I soldered the wire next to the gray (negative) to the middle switch. Then I soldered a lead running from the switch to the left hole (negative), and soldered the other lead on the capacitor to the right hold on the board. The only thing that matters is the Polarity. You can have the switch on either side of it. If you still don't get it PM me you # and Ill give you a call. (I just don't fell like taken pictures right now)

[mrwonkaland]

hi. i dont know much about fixin these electronics but i can learn pretty fast. i was wondering if you could help me with my dimebag wah pedal. its not crying anymore. and that makes me sad. i thought it was the pot. but on ur blog u say its the capacitor. id rather take ur word over my assumption. id really appreciate it if you could help me out. u say to leave a #. i dont know if you were talkin to someone else or just offering yourself. but in any case, my number is 602.295.0008. my email is [e-mail] thx for your time.

[stupidityisagift]

hey, im a lil confused. is this mod for switching from the wah, to the volume mod, or is it wah volume combonation? thx

[James Haskin]

The switch cancels out the wah circuit and turn it into a wah pedal. The rest of it changes the tone of the pedal.

[oweng4000]

I had an idea for a mod that i hope will work. a switch on the side in order to switch inductorPr

[James Haskin]

Sounds like the MXR Custom Audio Electronics MC-404 Wah. Check it out.

[trgz]

I've got an old Cry Baby that, way back in the 80's, I modded it to be a Wah/Volume and I only used a couple of parts in the mod, sadly though I can't remember what they were but I suspect I managed it with a simple change to the stomp switch and/or pot (multi-way versions),- it might have shorted out/bypassed a section of the circuitry like above (James H). It's up in the loft but I un-modded it when I went thought about selling it (20 years or so ago).

[mabu4237]

Where does the switch for volume wah switching go?

[spiceyweasel]

Sick! I've got a vintage Morley Distortion/ Wah pedal that also can be used for volume control. It'd be cool to add a few ring-dings to it. Thanks.

[psychodeathmonkey]

Hey anyone know what i need to make my wah into a wah/ring modulator like the snarling dogs mold spore or the arctec wish wah? I like the pedal ive got and dont really feel the need to buy another pedal. so anyone know what id need to do it. I pretty much know the basics , pots ,wires, and some kind of resisters, capaciters and all that stuff so. anyone help me out?

[ReoTheYokel]

You can prevent "sucking" the tone by using one of those True Bypass pedals. Or something like that. Justin Sandercoe reviewed it in one of his videos on Youtube. But, yeah, this is cheaper.

[James Haskin]

The way I wired it, using the switch, this pedal is true bypass.

[James Haskin]

http://www.youtube.com/watch?v=M7QL37nKcR0
Oh this is pretty cool. I actually like leaving my wah in a position at times but this it pretty cool. I'll buy one of these for the dimebag wah from hell. It would be great soloing.

[mondaymonkey]

I splurged and got myself a Dunlop 535Q. Love it to bits, but need a light to tell me if its on or off. I'm probably just going to have another push switch connected to a small battery and LED mounted on the underside of the foot control pedal

[avibank911]

dono if this is the right place to ask but- how do i add a string of led's to my volume pedal to indicate the postion of the potentiometer

[James Haskin]

Idk dude, personally I don't think its worth the effort.

[no food please]

I'm looking into doing this, but I have the dime cry baby custom (model db-02). It contains mostly smd components and all of the circuit board traces are covered up and really hard to see. I can't find any pictures of other people working on it, or any circuit diagrams for it. There are some spots that don't have have anything soldered to them, but have traces leading up to them and labels (e.g. "C3" or "TP1").

[James Haskin]

http://www.musiciansfriend.com/product/Dunlop-DB02-Dime-Custom-Crybaby?sku=151013&src=3SOSWXXA
Is that it? Open up the case and remove the circuit board. Take some pictures of the inside for me. I'll try to understand what you mean.

[no food please]

That is the correct pedal. I suspect the DB-02 and the DB-01(which has a switch and a potentiometer on the side of the pedal) use the same circuit board(or a very similar one). Here are some pictures of the DB-02:
http://www.flickr.com/photos/28577578@N05/2669716865/in/photostream/

[James Haskin]

Ooooh. SMD, got ya. Well, I emailed Dunlop asking for a schematic (worth a try?) and private messaged butthead95 who I think has a DB-01. I figure you could maybe replace a few components on yours, drill a few holes and have a DB-02 that does everything the DB-01 does. If you really wanted to you could map out the circuit yourself and play with things but man thats A LOT of work.

[James Haskin]

butthead95 made this for us.
http://www.instructables.com/id/DB-01/
Sadly idt its gonna help you much. If I was you, I could try to sell yours and buy a DB-01 they seem really cool.

[KoenB]

Great mods! I never knew the sound would change so much by just changing caps.

All you need is my foot-on-pedal mod ;) check it out http://www.instructables.com/id/Foot-on-pedal-True-Bypass-crybaby-wah-mod/