Wah Inductors. No hype. Just measurements.

Also:

There is a lot of interbreeding between wah pedals.

Budda bud-wah? That one uses a Dunlop board, albeit a "custom" crybaby variant. Also a Dunlop shell.

I've read that VOX pedals were made using Dunlop parts as well. At least, up until their production shifted to China. They tended to use an earlier variant of the Dunlop board that omits the input buffer.

There are two different third party manufacturers in China that do the crybaby-style pedal that I know about.

The first produces the Eleca brand: these are typically identifiable via the horizontal striped pattern on the wah tread. Rocktron, Modtone: these are made in this factory. They're also built with the infamous lightweight aluminum enclosure that is sold on aliexpress, and the rocktron example I have even has a bunch of weights bolted near the heel position to give it more of a sense of heft.

Honestly: it's a perfectly serviceable enclosure. I actually like their version of treadle tension adjustment more than the Dunlop version. They also tend to use the Eleca halo inductor, which gets a thumbs up from me.

There's another manufacturer that operates out of China that uses heavier enclosures: Ruby Tubes, Guitar Research, Carvin: these can be identified via a diamond shaped pattern on the tread. My only complaint with these is that my ruby tubes tthat the plugs they used on this particular example were the "outie" variety, which made extracting the circuit board perilous.

Either of those examples are just fine, and good platforms for modifications. The basic wah circuit is present in all of them.

Another note: I've added a few more inductors to my document.

Other observations:

Regardless of the date, Thomas Organs were beautifully built. There's a real sense of craftsmanship to each, with the wiring harnesses expertly secured by a single length of waxed thread. The leads are terminated at wire wrapped posts that are soldered to the circuit board. Not quite turrets, but similar enough.

Dunlop immediately started making changes for the sake of mass-production. Quick connects and zip ties. When they started running out of the Thomas organ stock that they bought, they often switched to cheaper options. This is particularly noticable in the mid-80s models, which contain then infamous cylinder of death inductor. The Q is shit, they're up around 350 ohms on DC resistance, and they sound like ass.

Any other Dunlop inductor is AOK and potentially usable, though most are relatively tame in terms of Q, so if a sharper roll off around the resonant peak is desired, any of the commercially available 1811p/halo inductors will fit the bill.
 
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Update:

I've added a few more inductors, including one of the *legendary* inductors: the fabled 03 stack of dimes.

I suspect this guy is an N30 ferrite in an 11x7 package, wound with #38 wire, and dipped in epoxy. I'll be grabbing some N30s in that package soon to test my theory.

What I can say is that N48 doesnt have enough oomph behind it to hit 500mH with #38 wire. It could still be N48 with something like #40...I'll need to buy some and check that out. That stuff is like...oof. Like a human hair.

This SOD I picked up in an early 80's Dunlop crybaby. These were great pedals: sure, they're slowly switching over to greenie caps in this time period, but most of what they're throwing in the pedals is leftover stock from the acquisition from Thomas Organ.

From what I've read: after Dunlop ran out of the SOD inductors, they switched up to the blue can. This is, by far, the worst inductor that ever graced a crybaby. This was the case for the mid-to-late 80s. Eventually they wised up to the situation (likely because of customer complaints) and switched to the 1811P bound with a steel screw. The earliest example I have of a 1811P in a crybaby is 1990, but its possible those were produced before that year.

Steel screws aren't technically the right material for the task of binding an inductor together. Inserting a steel screw allowed Dunlop to use less winds of a thicker gauge wire in order to achieve a higher inductance. That said: they tend to increase heat dissipation, and their use is generally frowned upon. Probably part of dunlop's learning the ropes of making a mass-produced pedal with a very specific requirement for an inductor.

That said: they work just fine in the application. I don't have any notes. They're a serious step up from the blue cans, and you can make a great sounding wah with one. But I generally prefer what came after'

Dunlop switched to the 1408p pot cores with the brass screw in the center. This is a more acceptable material for binding inductors together, as it is not magnetic and doesn't tend to effect the measured inductance. Those were in use for the early 90s, and there is a good deal of variation between examples, with no clear trend based on when they were made. Generally, though, these tend to be great. Stickman approved.

Eventually those were switched for the exposed toroid in the mid 90s. These can be identified by the fact that the wire wraps are fully exposed on a donut-shaped inductor.

I suspect that Dunlop kept the same toroid in their black plastic cans, just with the plastic protecting the inductor. The resistance values match up, but I have a couple more to measure and I have yet to cut one of the black cans open to confirm, but that's on my list of things to look at.

The exposed toroids were used through the mid 90's. The black plastic cans first saw use in the late 90's, and there is a *ton* of variation between them. I suspect that Dunlop switched away from the 1408p's as the toroids required less turns of wire, owing to their lower measured resistance. Improved manufacturing processes likely spurred the switch, as I imagine Dunlop was pinching pennies on the wire used to wind these.

Future stuff: I gotta measure a few more that I've picked up recently that still need to be measured. I recently scored a *great* deal on my first JEN (italian-made) super cry baby with a white Fasel Inductor. It's a late model, likely late 70s or early 80s, as it uses carbon Film resistors. I'll be posting my findings on that guy too as soon as it comes in.

Afaik, Jen produced crybabies up until Dunlop bought the brand.

I'm going to be collapsing some of the inductors that I have *way too many of* in the list into averages soon in order to clean up the line charts.

I'm also going to be making about 5 "Stickman Industrial" brand wahs with some of my favorite mods, turret boards, all the stupid woo woo mojo components to help fund my research. I'll be doing the same with a bunch of these boards that I've accumulated as drop-in replacement kits. Probably on eBay or reverb or something. Cause I need MONEY. But I'm not overly concerned with turning a profit, just in getting some of what I put into this project back.

I'll also make up a few of my custom-wound inductors and send em to long-time members for free that show some interest so I can get a little feedback. So if you're interested...drop me a PM! Gotta limit it to one inductor per bro. And I likely won't be getting those made and out the door for at least a month here.

Rules: you've gotta be a well-known member here, you've gotta be able to pop one in a wah pedal soon after reciept and share your thoughts with me, and for the first 10 who ask I'll cover shipping.

If there's more? Probably gonna need to ask for shipping. Cross that bridge when we get to it.
 
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