Cry Baby wah mod?!?!

[Eric.nail]

So i recently have been enjoying the music of Steve Vai, Orionthi, 80s heavy metal hair bands...You know the works!
This is an odd thing for me...I usually stick to more alternative bluesy bands or more rock bands like the killers.

In my ridiculous shredder kick, i decided to buy a wah pedal. Picked it up for 80 bucks easy...I hate it.
its a regular cry baby wah pedal...Nothing special. Its pathetic! You get a massive volume jump, a click and no indicator light the damn thing is on! wtf?!?!?

not to mention it muddies up my tone in standby. I was like EFFF that....

Ripped the thing appart yesterday. installed a blue indicator, true bypass switch...

Took care of the main issues for sure, but i already modded it once, what else can i do?
I'd love some ideas! toss em my way i'll be your best friend.

[Joe Hart]

I like to lower the Q. It really thickens things up. That would be my vote for biggest "bang for your buck"!
-Joe Hart

[paulyy]

You can raise the stock 1.5k resistor to 1.8k or 2k for more midrange. Raising the first 103/10nf cap to 104/100nf or more Will bring up the bass. Lowering the 68k resistor to 47k will help bring up the volume.
Raising the 470 ohm resistor will give you less gain and raising it will give you more gain. Raising the other 103/10nf cap will change the frequency by giving it a darker sound and changing the 33k resistor will
change the Q or vocal quality of the pedal. Hope that helps

[Paul Marossy]

You could try this, some people like these mods I did my own GCB-95:
http://www.diyguitarist.com/DIYStompboxes/WahMod.htm

And this one is cool too:
http://www.diyguitarist.com/DIYStompboxes/WahMod1.htm

[flemingmras]

First off...get rid of the buffer circuit. This changes the way the circuit input loads your pickups, which will drastically change things. Install a DPDT bypass switch and wire it up for true hard bypass (this is what Dunlop should've done in the first place).

Then...change the emitter resistor on the input stage to a 470R.

Change the 33K Q resistor to a 100K. This raises the Q, which narrows the pass band of the boost and gives you the perception of having a much wider sweep range. Also makes it sound much more "vocal" ala Jimi Hendrix.

I also change out the MPSA18 transistors for either 2N5172's or standard 2N3904's. MPSA18's have a very high hfe...wah circuits IMO fare much better with low - medium hfe transistors.

Try this and see how you like it.

[pinkjimiphoton]

go to geofex.com

rg answered all a long time ago. seriously.

my wah was a bone stock gcb95.....

now i call it the puke wah...it sounds like a baby booting...satan's baby.

for real!!

[Paul Marossy]

First off...get rid of the buffer circuit. This changes the way the circuit input loads your pickups, which will drastically change things. Install a DPDT bypass switch and wire it up for true hard bypass (this is what Dunlop should've done in the first place).

I understand that the buffer fixes the classic problems when using a Fuzz Face and a wah together. And it prevents "tone sucking" when in "bypass" mode since the original design uses a SPDT switch and the ciruit is always connected to the input. Yes, true bypassing can fix that problem if there is no input buffer present (as in the terribly tone sucking "vintage" wah pedals).

Personally, I don't hear much of a difference between a buffered non-true bypass and an unbuffered true bypassed wah pedal. I suppose that it might be more noticeable with single coil pickups vs. humbuckers? I only use humbuckers myself...

[zombiwoof]

First off...get rid of the buffer circuit. This changes the way the circuit input loads your pickups, which will drastically change things. Install a DPDT bypass switch and wire it up for true hard bypass (this is what Dunlop should've done in the first place).

I understand that the buffer fixes the classic problems when using a Fuzz Face and a wah together. And it prevents "tone sucking" when in "bypass" mode since the original design uses a SPDT switch and the ciruit is always connected to the input. Yes, true bypassing can fix that problem if there is no input buffer present (as in the terribly tone sucking "vintage" wah pedals).

Personally, I don't hear much of a difference between a buffered non-true bypass and an unbuffered true bypassed wah pedal. I suppose that it might be more noticeable with single coil pickups vs. humbuckers? I only use humbuckers myself...

I don't think the input buffer fixes the wah-into-fuzz problem, I think it was just Dunlop's method to fix the tone-suck in bypass.  From what I've read, you still need to put in an output buffer to make it work in front of a Fuzz Face.  Only some of the Dunlop wahs have real true bypass, which they call "true hardwire bypass".  The ones that say "hardwire bypass" are not real true bypass, but usually have the input buffer to counter the tone-suck in bypass.  There is an article on bypass on the Dunlop Blog, which also lists all of their pedals and what type of bypass they have:

http://www.jimdunlop.com/blog/what-is-true-bypass/

Also, as for the suggestion earlier to change the 33k resistor to 100k, I did that with my Vox V 847 (the older Dunlop USA-made version, not the recent Chinese-made V 847A), and found the "Q" was too drastic.  I recommend trying something like 68k, or hooking up a pot there, finding a good setting, and measure the pot for the value resistor to put in.  Just a suggestion.

Al

[Paul Marossy]

I don't think the input buffer fixes the wah-into-fuzz problem, I think it was just Dunlop's method to fix the tone-suck in bypass.  From what I've read, you still need to put in an output buffer to make it work in front of a Fuzz Face.  

Yeah, I think you're right about that, the output buffer is what's needed. I'm not a wah + fuzz kind of guy.  

Anyway, my main point is that I don't feel that the buffer changes anything but the tone sucking. But I haven't used single coil guitars with a wah pedal, either. I can't tell a difference using my humbucker equipped guitars.

[joegagan]

alan, agree on the output buffer.  however, if you use an input gain pot on a fuzzface type, this also seems to solve the problem. makes sense, and lets you have one less buffer in chain when your wah is on without the fuzz. besides, doesn't the fuzz go before the wah?

i also agree on the 100K/33k voice resistor. it depends on a bunch of the other stuff in the circuit, it is possible that this mod works well with mostly stock gcbs, not sure. anyway, tune to taste once other components have been changed if youask me. plus, some people like the wah tone of the early vox or colorsounds that had no resistor at all in this position.

as far as the input buffer of a gcb, in my testing, for the wah tone it adds a little balls and some extra high end vs bypassing it, but again, if you are going to mod the whole wah, this difference becomes fairly minute. leave it in if you want a modern wah with strong treble, take it out if you want a vintage warm old time sounding wah , in general.

[Paul Marossy]

i also agree on the 100K/33k voice resistor. it depends on a bunch of the other stuff in the circuit, it is possible that this mod works well with mostly stock gcbs, not sure. anyway, tune to taste once other components have been changed if youask me. plus, some people like the wah tone of the early vox or colorsounds that had no resistor at all in this position.

According to the original wah patent documents, the purpose of that resistor is to lower the "Q" because it was "found desirable" to lower the "Q" as the circuit had a very high "Q" without it. Obviously, this is a personal preference thing...

[flemingmras]

Yes it is an OUTPUT buffer that is needed to fix the wah/fuzz issue. The INPUT buffer was to fix the tone suck issue without the use of a DPDT bypass switch. But with the input buffer the circuit will not load your pickups exactly the same as the "classic" wah circuit.

As to the 100K resistor, I'm a huge fan of the Vox Clyde McCoy circuit, which used the 100K resistor. I personally like a very pronounced/drastic/dominant/"in your face" wah tone myself...not into "subtle" wah's at all, so I personally prefer the 100K. Your tastes may vary.

A note on "Q"....some of you have it backwards. When you RAISE the Q, you are NARROWING the boost pass band whereas when you LOWER the Q you are WIDENING the boost pass band. A narrower pass band gives the perception of a wider sweep range, makes the wah more vocal/more dominant whereas widening the pass band gives a less vocal/less dominant wah sound.

[Seven64]

i like to leave the input buffer in so that you can perform the fatwah mod posted above. 

[zombiwoof]

alan, agree on the output buffer.  however, if you use an input gain pot on a fuzzface type, this also seems to solve the problem. makes sense, and lets you have one less buffer in chain when your wah is on without the fuzz. besides, doesn't the fuzz go before the wah?

i also agree on the 100K/33k voice resistor. it depends on a bunch of the other stuff in the circuit, it is possible that this mod works well with mostly stock gcbs, not sure. anyway, tune to taste once other components have been changed if youask me. plus, some people like the wah tone of the early vox or colorsounds that had no resistor at all in this position.

as far as the input buffer of a gcb, in my testing, for the wah tone it adds a little balls and some extra high end vs bypassing it, but again, if you are going to mod the whole wah, this difference becomes fairly minute. leave it in if you want a modern wah with strong treble, take it out if you want a vintage warm old time sounding wah , in general.

I agree completely with your observations!.
Al

[Paul Marossy]

i like to leave the input buffer in so that you can perform the fatwah mod posted above. 

Ha ha, +1 for leaving in the input buffer!

[Eric.nail]

Hey thanks guys! I'ma get on the tinkering tonight after rehearsal. 

by the way, i left the pedal stock but instead routed the ins and outs through a 3PDT swtich. what was dunlop thinking by not doing this in the first place?
poor design...

[Joe Hart]

I just picked up a red Fasel inductor and with no other changes, it made my Cry Baby a little fatter, a little smoother with the sweep, and a little more "expressive" (I can't think of a better word for it). Not a huge difference, but a noticeable one. Just an observation.
-Joe Hart

[joelindsey]

Just performed the following on my newer Vox wah:

68k input resistor dropped to 47k
470 emitter resistor on Q1 to 220
0.01 input cap to 0.1
33k replaced with 100k pot
mpsa18's replaced with 2n304's

Liking it so far. It was a real pain to work around the surface mount components. Next order of business is to cut down the rubber pads on the toe end of the rocker. They really cut down on the travel distance which is the main reason I was using my Crybaby instead because the rubber pads are smaller

[Paul Marossy]

Yeah, increasing the value of the input cap alone would fatten it up a lot I would imagine. Never thought about trying that...

[pinkjimiphoton]

FWIW,
i tried about 8 different buffers on my crybaby...and found a simple resistance worked better to make it play nice with distortion if the wah was before them. none of the buffers did squat if i ran the wah first...kick on any fuzztone, and the wah seemed to go away. now i run my fuzzes first, then wah, then distortions/overdrives. seems to work better.

your mileage may vary, but i found the output buffer thing to be a complete waste of time...including cloning the commercial unit that's supposed to fix the problem suggested here and on the "forbidden" forum..