What should I do to my wah pedal?

Try a 250K tone pot.

If your wah still sucks after that, I'll punch myself in the nuts for you.

So far no one's said anything specific about tone pots.

That was the secret sauce that worked for me at least, and this just spits in the face of your typical coffee snob....Just pour some hot water on your instant coffee.

Initially I modded my pawn shop Dunlop crybaby to the 'stinkfoot' specs posted online...True bypass wiring 3PDTor is it a dpdt....(That sounds like an innuendo!)

Bypassed the buffer (So I have to now run a JFET boost after the wah now or it's very weak... but that is pretty gnarly because I can 'salt to taste' that way if I want it flaming hot or quiet as a church mouse) swapped a few resistors and caps to the suggested 'stinkfoot' values, sure you could play around here, at that point I might as well build a wah from scratch and spend time doing the proper bean counting nerd science stuff here tone chasing the elusive dragon.

Upgraded to a Red fasel coil....But it still needed something, the mids in the travel was just kinda dull. It's a reissue Red of course. (I took the pepsi Challenge, I chose JIFF peanut butter) Look I'm just never gonna know the difference anyway between the real McCoy, and the Reissue Marketing Gimmick hype....Unless you have an original coil you'd sell me, but that's throwing pearls before swine in my case.

We all want that mystical fricken tone of an original, but not everyone else is going to be able to have that, at the prices of originals.

shhh It can be our little secret, I won't tell. Neither will the audience of people you're performing for....Believe me, not one guy in the crowd will point that out 'Aww man, he's not using the Toroidal inductor... what a total poser!!'

Me: Waiter, Yes...I'd like to order a veal steak please

(Chef to the waiter behind the closed kitchen door, hey, we're out of veal!!)

Chef: * Takes a mallet and pounds a porkchop to a pulp.*

Waiter: *serves it to me*

Me: *Covers it in hot sauce and pays for the full price of the veal steak and goes home full yet none the wiser.*

I couldn't find a 250K 'wah' pedal tone pot so I just took the little 'gear' off the original stock 100K pot, and Jammed it on a Cheap $6 generic 250K guitar tone pot and stuck it in.

'Inconceivable!!!!'

Well, if it works...is it really a dumb idea?

According to research some well known legend *cough*Hendrix*cough* had a 250K tone pot in his Wah at some point? and looking into it, all I could find where the stock 100K pots and a few places were schlocking 200K pots for a lot more money....You pay mostly for marketing gimmicks and hype. Am I right or am I right?

I kinda suspect the 250K tone pot thing is like some kinda forgotten hidden secret or they'd be producing them, it seemed like it was something I was not supposed to know, or do, but ' I am Ahab, I will shoot out the sun if it suits me. '

Other than adjusting the travel, I think the 250K tone pot made the mids really gnarly. I'm not saying I made it any better than a stock wah, sometimes that's fine, I've had situations where my gear is not working in a recording session or someone hates it, at that point I got a stock crybaby on hand that is fine, just fine.

That said, My setup is irregular, I run vintage lo-fi Portable transistor radios for guitar amps and modded guitar as well.

It was just fun to try modding it out...It's still a better door stop.

What have you got in there right now for a tone pot?

Apparently most people like to plug their fuzz after the wah in their effects chain? I'm backwards, I'll run a fuzz into my wah, it just sounds more nasty.

Also, I painted my wah pedal GOld sparkle with a Red heart on the foot pad, with some nail polish. Far out man....Surprisingly that didn't make it sound any better.
 
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I suggest keeping it simple and focus on 'Q' for more vowel, to which the Clyde McCoy circuit delivers. IMHO, that is the gold standard for a musical effect.

Set the potentiometer gear so that the frequencies are more centered on the crossover point where the mids seem to 'jump' from low mids to middle-mids and avoiding the harsh treble when toeing in to turn off the effect. Also, set the treadle action just tight enough to hold a fixed position. I am also using no buffers and a rely-based true bypass.

I am literally waiting on a Halo 500mH inductor to be delivered tomorrow, to complete the simple Clyde McCoy terrraboard build. I am using 2N2222 NPN transistors, hand selected on hFE (gain), to replicate the vintage BC109B (I think the four I have in stock are from the late 60's, early 70's). Gain between 180 and 240 seem to be the sweetspot.

I am using only the bare treadle from a donor Dunlop 535Q wah, which as tweakable as it was, didn't have a good tone in it. There were no parts that could be recycled, as getting the double-sided PCB to give them up without damage, was not happening.
 
You mean those awful board mounted 6-pin quarter inch input Jacks Dunlop uses as a deterrent to keep me from tampering with their board?

Yeah I trust the infinite secret wisdom of the corperate gods to serve me goop, and make me like it.

... I get finicky and loose contact whenever I go to plug any cables in? If my pedals don't make sound when I plug them in....guess what?

Yeah I sincerely despise those too, I'd be better off building a wah from scratch and gutting the original Dunlop board. True say. I'm not worried about using all the correct to spec boutique components, you guys deserve those magical vintage parts more than a guy like me.

Close enough.

I didn't touch the stock Transistors, hm...do you think using a 250K tone pot with the original stock transistors might lend the midrange some more punch? Is that what I'm hearing? Measuring transistor gain, or should I mod it out with Bias trimpots? Let's get a little crazy here. Tell you what.

Germanium or Silicon? Who do you like better, Stones or the Beatles? (correct answer: The kinks)

Are your milkshakes made with real milk or are you guys using that constituted shake mix stuf?

Uh, we have Vanilla, chocolate, and Strawberry sir. Would you like fries with that?

That said, I am always constantly re-adjusting the travel, because it's different with every guitar and amplifier I'm plugging into.

....'Ok new guy, take it easy, calm down....'

I'm still curious what Tone pot Values you guys are using for your wah, these are variable resistors, yes?

How does Tone pot value affect the notch filter sweep?
 
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Dumpster D said:
Germanium or Silicon? Who do you like better, Stones or the Beatles? (correct answer: The kinks)

Are your milkshakes made with real milk or are you guys using that constituted shake mix stuf?

Uh, we have Vanilla, chocolate, and Strawberry sir. Would you like fries with that?

I'm still curious what Tone pot Values you guys are using for your wah, these are variable resistors, yes?

How does Tone pot value affect the notch filter sweep?
Click to expand...

Lol. I think can answer a few of your questions:

The potentiometer is a component of a resistance-capacitance high pass circuit. It is in parallel with a 470K resistor that both passes and blocks full frequency. The circuit with the pot allows there to be less resistance for higher frequencies. The potentiometer variable sweep (lug #2) changes the frequency center and simultaneously, how much more highs pass by function of lower resistance. This circuit becomes the signal for Q2, which the phase is altered by the negative feedback created by the inductor-resistor circuit before it. That dictates how broad or narrowly focused the EQ effect sounds, going from a broad rise, in trebles, mids or bass, to a vowel sound (sweet spot), to a 'whistle' sound (very tight 'Q').

So, the circuit with the inductor, resistor capacitor has the greatest effect on the 'notch' (Q) of the wah. The pot, to a smaller degree.

Rasing the resistance value of the pot will shift the frequencies lower, which may sound better to a bedroom player or a solo act. I prefer the stock 100K, because it has the right grouping of frequencies to cut in a band mix. Like I stated before, the mid shift 'knee' is what really stands out to the human ear for the effect. I avoid the harsh treble end of the pot travel.

Germanium transistors are good for fuzz or an edge of breakup Rangemaster type boost, especially if complimented with silicon transistors in later stages. They definitely color your signal unpredictably, due to their sensitivity to temperature changes. I would not recommend them for a wah. The reason David Gilmore, Jimi Hendrix and countless others in the 60's went to guys like Pete Cornish, was to have the Germanium transistors removed from their effects, for more reliable silicon transistors. Cornish would audition silicon transistors to replicate the sweet spot sound of the original transistors, without the temperature inconsistencies.

Beatles, Stones and Kinks - yes please. Anyone of those would be fantastic to listen to at any given moment.
 
Dumpster D said:
You mean those awful board mounted 6-pin quarter inch input Jacks Dunlop uses as a deterrent to keep me from tampering with their board?

Yeah I trust the infinite secret wisdom of the corperate gods to serve me goop, and make me like it.

... I get finicky and loose contact whenever I go to plug any cables in? If my pedals don't make sound when I plug them in....guess what?

Yeah I sincerely despise those too, I'd be better off building a wah from scratch and gutting the original Dunlop board. True say. I'm not worried about using all the correct to spec boutique components, you guys deserve those magical vintage parts more than a guy like me.

Close enough.

I didn't touch the stock Transistors, hm...do you think using a 250K tone pot with the original stock transistors might lend the midrange some more punch? Is that what I'm hearing? Measuring transistor gain, or should I mod it out with Bias trimpots? Let's get a little crazy here. Tell you what.

Germanium or Silicon? Who do you like better, Stones or the Beatles? (correct answer: The kinks)

Are your milkshakes made with real milk or are you guys using that constituted shake mix stuf?

Uh, we have Vanilla, chocolate, and Strawberry sir. Would you like fries with that?

That said, I am always constantly re-adjusting the travel, because it's different with every guitar and amplifier I'm plugging into.

....'Ok new guy, take it easy, calm down....'

I'm still curious what Tone pot Values you guys are using for your wah, these are variable resistors, yes?

How does Tone pot value affect the notch filter sweep?
Click to expand...
Hey now.

This forum only has enough room for one long-winded weirdo who's specifically really into the magic sauce of how a wah pedal wahs.

Back off, jack. This is my territory.

*Shakes fist*

I've actually got some insight to this.

There was a bit of strangeness in the dunlop JH-1 model in the mid 90s, where for a brief time there was a JH-1S (special) model.

The JH-1S one was identical to the JH-1 they produced beforehand, with the exception of a Hotpotz II 470k potentiometer on the sweep.

Honestly: I get the feeling it was the result of a potentiometer order that got fucked up where they decided to make lemonade out of lemons. That's not based on anything but supposition though: This was well into the 1990s, a decade after dunlop acquired the brand from Thomas Organ, long after jimi used a wah.

The JH-1 was identical to the GCB-95 that dunlop produced at the time, with the exception of the value of the range cap. The JH-1 used a 22nF cap, the GCB-95 uses a 10nF. It's enough to shift the range down a bit, but its not super similar to the one Jimi used.

AFAIK: Jimi used a "picture" wah, which was a Vox-branded wah made by EME in Italy for the Thomas Organ Company. It got really *weird* in the early years. After a couple years Italian production moved over to JEN and stateside production was based in California. Two different lines, utilizing different board and Inductor designs. Wild.

Legend has it that Jimi was using a picture wah with a halo inductor...which just refers to the specific assembling hardware that was used to affix the ferrite halves together. Same with the "trashcan" variants: those are just a different kind of hardware for housing the 18mm diameter x 11mm tall inductor assembly.

I've got an EME from about a year and a half afterwards...during the "transition" period. That one's just the bare ferrite, no assembly hardware. What I know about the EME wahs is that they used a potentiometer that is stamped with the letters "ICAR". They're nominally 100k, but probably had a tolerance of 20% or more.
 
andrewsrea said:
The potentiometer variable sweep (lug #2) changes the frequency center and simultaneously, how much more highs pass by function of lower resistance. This circuit becomes the signal for Q2, which the phase is altered by the negative feedback created by the inductor-resistor circuit before it.
Click to expand...

What was that last part about negative feedback?

Is that what you'd give me if I sold you my 'custom' wah pedal on ebay?

Hey Five bucks is five bucks.
 
Dumpster D said:
What was that last part about negative feedback?

Is that what you'd give me if I sold you my 'custom' wah pedal on ebay?

Hey Five bucks is five bucks.
Click to expand...

If you look at the schematic there is a circuit which connects Q1's base to Q2's emitter and to its own collector. That is a negative (out of phase) feedback loop from Q1 to Q1 and a positive (in-phase) feedback loop from Q2 to Q1.

If feedback is in-phase to the base, it adds to the original signal and out of phase it will subtract. Since there are a couple resistor-inductor-capacitor EQ circuits attached, the addition or subtraction becomes frequency dependent - it will only add or subtract the frequencies of the feedback loop.

It is a complicated and clever circuit, which I suspect the principles came from radio transmitter or receiver tuning circuit design (which is why some poorly shielded / functioning wah's will pick up AM radio signals).
 
Ah so that's what accounts for it!!

I've definitely heard a few wah pedals spitting Fire and Brimstone at me late at night when left tuned in, Half-cocked.
 
If you search my old posts you will find all the possible modifications to the circuit and to the enclosure, but at the end of the day I vote for door stop or sheet lock :ROFLMAO:
 
I've watched most of this guy's videos but this old one has a bunch of mods in it.

I modded mine to true bypass, I added a switch to go into a volume pedal mode (different video), the mid control, the freq sweep control, and added a switch to change the cap from the original to the cap that he swaps for the "hendrix mod" in this video.

I didn't really pay attention to the difference before and after true bypass but I have enough buffered pedals on my board so why not make it true bypass if the wah buffer sucks anyway.
Volume pedal mode I'd say is unnecessary but that's dependent on where you like volume pedals and whether your wah is in that same spot.
The mid control knob is definitely worth it!
Freq sweep knob was pointless so I removed it and then used that hole for the mid control instead.
Putting the "Hendrix" cap on a switch was worth it I'd say as well to have another voicing. You could keep trying different caps as well if you wanted of course.

I still haven't tried swapping inductors on either of my wahs but that mid control makes a big difference in allowing you to shape the tone of it.
 
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