masonlewisdiesel
Member
I'm on the home stretch!! gonna be a late night
Wah Inductors. No hype. Just measurements.
- Thread starter Stickman393
- Start date
Stickman393
Well-known member
So I'm lagging like fuck on my international shipments. But I'm gonna add in a little extra somethin somethin for yall.
As for now, I've added a few more inductors to my original doc, and I've made this one comparing various potentiometers:
docs.google.com
Other notes:
Mission rewah: this guy ain't made no more. Got two of em. The standard and the pro. Gonna trace em out and see what the little dip switches on the inside do. Got a feeling about a couple of 'em.
Looks like the only difference between the "pro" and the standard is the inductor. The "pro" uses a cine-mag crossover inductor with several different taps on it. The only tap that is actually used is the 520mH tap: all the rest are electrically isolated from the circuit. I had read some speculation online that the little internal dip switches on this guy would switch between the taps on the inductor: this is not the case.
The standard model uses a yellow fasel. Which is a great inductor.
The biggest difference between the two? The cine-mag inductor has the highest q I think I've ever measured in the 4k range.
I've also picked up a few off brand wahs to check out: the Tech 21 Killer Wail, made by Onerr, uses a toroid that initially measures pretty "blah", but sounds damned decent in practice. They achieve this by adding a 47 ohm resistor in series with the inductor coil, bumping the "q" resistor and input resistor to 100K, and dropping the resistance off the emitter of Q1 to 220 ohms. Makes for a decent little wah!
I've also picked up an Ibanez WF-10 that is in *shitty* condition. I'm not sure if I'm gonna try to salvage the plastic enclosure or not yet: trying to 3d print the enclosure has been an exercise in failure, I need to invest in a dedicated support filament in order to make this thing work.
Also bought a Twin Peaks cause I wanted to crack it open and see what they did on the inside. All SMD. dammit...
As for now, I've added a few more inductors to my original doc, and I've made this one comparing various potentiometers:
Wah Pots
Other notes:
Mission rewah: this guy ain't made no more. Got two of em. The standard and the pro. Gonna trace em out and see what the little dip switches on the inside do. Got a feeling about a couple of 'em.
Looks like the only difference between the "pro" and the standard is the inductor. The "pro" uses a cine-mag crossover inductor with several different taps on it. The only tap that is actually used is the 520mH tap: all the rest are electrically isolated from the circuit. I had read some speculation online that the little internal dip switches on this guy would switch between the taps on the inductor: this is not the case.
The standard model uses a yellow fasel. Which is a great inductor.
The biggest difference between the two? The cine-mag inductor has the highest q I think I've ever measured in the 4k range.
I've also picked up a few off brand wahs to check out: the Tech 21 Killer Wail, made by Onerr, uses a toroid that initially measures pretty "blah", but sounds damned decent in practice. They achieve this by adding a 47 ohm resistor in series with the inductor coil, bumping the "q" resistor and input resistor to 100K, and dropping the resistance off the emitter of Q1 to 220 ohms. Makes for a decent little wah!
I've also picked up an Ibanez WF-10 that is in *shitty* condition. I'm not sure if I'm gonna try to salvage the plastic enclosure or not yet: trying to 3d print the enclosure has been an exercise in failure, I need to invest in a dedicated support filament in order to make this thing work.
Also bought a Twin Peaks cause I wanted to crack it open and see what they did on the inside. All SMD. dammit...
Last edited:
Stickman393
Well-known member
Updates:
I'm dying to build a little wah pot tester. Something that I could, say, stick a pot in, directly tie the shaft of a stepper motor to, and run a program where it spins the pot from min to max and auto-populate an excel sheet with the resistance over its travel.
I had done the previous one by simply turning by hand until each tooth of the gear lined up with the center. It works, but there's a hell of a lot of room for measurement errors, as wah pots tend to have a very specific obtuse-z shaped weep to em, where the majority of the change is in a small portion of the shaft travel.
That'll require acquiring new skills. Not much of a programmer. But I can probably figure it out.
Sad news: fucking, god dammit El Rad. In the process of trying to pull an El Rad 500mH inductor from an EHX crying tone pedal, I learned the hard way that they constructed those with toroids, soldered the ends to basic bus wire leads, popped the assembly in a plastic cup, and filled the contraption with a dielectric dope with a very low melting point. That is to say: upon trying to de-solder the thing a lead popped out of the thing with like, no effort. So, balls.
So, I pulled the toroid out. Couldn't seem to grab the wire that fell off in all the dope. Fucking thing. So, I was hoping to get an el-rad on the sheet...but it's starting to look like I'll need to re-wind that thing by hand if I want to get an idea of what that one's like.
Its a big ol oopsie, cause crying tone pedals and boomerangs use El Rads. Woulda been great to have added that to the list, and those pedals are fuckkking expensive on the vintage market.
Oh well.
I've upgraded my setup: the motor side of my coil winder with some PET-CF17. Much stiffer than my old PETG build. I'll probably swap the stabilizer side as well, but that'll take some doing. Bearings are a PITA to slide onto a shaft.
I've also been experimenting with an 1107 size, ala stack of dimes. Size comparison with a 1811. Both wound about 520mH@1K.
I'm dying to build a little wah pot tester. Something that I could, say, stick a pot in, directly tie the shaft of a stepper motor to, and run a program where it spins the pot from min to max and auto-populate an excel sheet with the resistance over its travel.
I had done the previous one by simply turning by hand until each tooth of the gear lined up with the center. It works, but there's a hell of a lot of room for measurement errors, as wah pots tend to have a very specific obtuse-z shaped weep to em, where the majority of the change is in a small portion of the shaft travel.
That'll require acquiring new skills. Not much of a programmer. But I can probably figure it out.
Sad news: fucking, god dammit El Rad. In the process of trying to pull an El Rad 500mH inductor from an EHX crying tone pedal, I learned the hard way that they constructed those with toroids, soldered the ends to basic bus wire leads, popped the assembly in a plastic cup, and filled the contraption with a dielectric dope with a very low melting point. That is to say: upon trying to de-solder the thing a lead popped out of the thing with like, no effort. So, balls.
So, I pulled the toroid out. Couldn't seem to grab the wire that fell off in all the dope. Fucking thing. So, I was hoping to get an el-rad on the sheet...but it's starting to look like I'll need to re-wind that thing by hand if I want to get an idea of what that one's like.
Its a big ol oopsie, cause crying tone pedals and boomerangs use El Rads. Woulda been great to have added that to the list, and those pedals are fuckkking expensive on the vintage market.
Oh well.
I've upgraded my setup: the motor side of my coil winder with some PET-CF17. Much stiffer than my old PETG build. I'll probably swap the stabilizer side as well, but that'll take some doing. Bearings are a PITA to slide onto a shaft.
I've also been experimenting with an 1107 size, ala stack of dimes. Size comparison with a 1811. Both wound about 520mH@1K.
What if you couples the pot with a larger gear couples to a much smaller gear and plotted the pots to each turn of the smaller gear(which has a handy little handle.
Would be a bit of filament but analog enough to not be toooo tough. Or repurpose a bike gear with a 3d printed gear. I'm sure some of the local nerd have a a spare bike gear made of titanium they could donate to the madness, err..., effort.
Just be careful not to get caught in the machine. Would hate for you to get corrugated.
Would be a bit of filament but analog enough to not be toooo tough. Or repurpose a bike gear with a 3d printed gear. I'm sure some of the local nerd have a a spare bike gear made of titanium they could donate to the madness, err..., effort.
Just be careful not to get caught in the machine. Would hate for you to get corrugated.
Stickman393
Well-known member
I'm uncorrugatable. Lucky for me, corrugation requires a third dimension.
Honestly, a stepper-to-pot setup would be the easier option here. Just requires a 1/8" to 1/4" coupling and a couple bits of L-bracket designed to be mounted parallel to each other.
Stepper motors are about 200 steps a rotation, It would be easy enough to configure that thing with 16x microsteps and achieve a resolution of 3,200...or roughly 0.1125⁰ a step. For a 300⁰ pot, that represents potentially 2,666 potential data points.
Probably overkill.
Truthfully, the easier way to do this would probably be time-based. Take a measurement every half second and configure a full 300⁰ turn to take 1 minute. Synchronize the starts. That sort of thing.
Honestly, a stepper-to-pot setup would be the easier option here. Just requires a 1/8" to 1/4" coupling and a couple bits of L-bracket designed to be mounted parallel to each other.
Stepper motors are about 200 steps a rotation, It would be easy enough to configure that thing with 16x microsteps and achieve a resolution of 3,200...or roughly 0.1125⁰ a step. For a 300⁰ pot, that represents potentially 2,666 potential data points.
Probably overkill.
Truthfully, the easier way to do this would probably be time-based. Take a measurement every half second and configure a full 300⁰ turn to take 1 minute. Synchronize the starts. That sort of thing.
Stickman393
Well-known member
Well folks, I got my first vox, and right away it went under the knife.
VOX wahs have never been appealing to me due to the fact that they're...well...
Here's the rub. Vintage vox wahs we're often made by the same Thomas Organ factories as crybabies, and they were built using the same parts. Thing is: they command a heftier price on the vintage market than the Thomas organ branded wahs. As such, given the increased cost of picking one up and the fact that it likely won't show any real difference over the TO's, I've skipped over those.
When vox wahs came back in the 90s or so, they were made by Dunlop. They retained the old ref F or so circuit board layout with some minor changes to power supply filtering, and Dunlop components. Easy enough to see by pictures, no need to buy one and pull it apart.
Nowadays, most Vox wahs are made in China. They use a combination of SMD and through hole components, and TBH I'm not super interested in many of the more modern mass-produced pedals. And they're still like 50 bucks minimum. Eh. I'm fine.
This one piqued my interest though. The Joe Satriani Big Bad Wah. Dual inductor model, foot switchable. Huh!
So, I took a look. Got one for a song. And I've added an additional page comparing the two inductors in this pedal.
The result? Huh. Pretty similar. The biggest differences are in Q, where the taupe inductor is generally higher, and in measured inductance, where the taupe starts lower and ends higher than the black.
Overall, though? Subtle. Not much difference. These measure quite similarly to many of the Dunlop toroids, so I suspect that they're using toroids in these.
Anywho, I added an extra page to my doc looking at those two.
VOX wahs have never been appealing to me due to the fact that they're...well...
Here's the rub. Vintage vox wahs we're often made by the same Thomas Organ factories as crybabies, and they were built using the same parts. Thing is: they command a heftier price on the vintage market than the Thomas organ branded wahs. As such, given the increased cost of picking one up and the fact that it likely won't show any real difference over the TO's, I've skipped over those.
When vox wahs came back in the 90s or so, they were made by Dunlop. They retained the old ref F or so circuit board layout with some minor changes to power supply filtering, and Dunlop components. Easy enough to see by pictures, no need to buy one and pull it apart.
Nowadays, most Vox wahs are made in China. They use a combination of SMD and through hole components, and TBH I'm not super interested in many of the more modern mass-produced pedals. And they're still like 50 bucks minimum. Eh. I'm fine.
This one piqued my interest though. The Joe Satriani Big Bad Wah. Dual inductor model, foot switchable. Huh!
So, I took a look. Got one for a song. And I've added an additional page comparing the two inductors in this pedal.
The result? Huh. Pretty similar. The biggest differences are in Q, where the taupe inductor is generally higher, and in measured inductance, where the taupe starts lower and ends higher than the black.
Overall, though? Subtle. Not much difference. These measure quite similarly to many of the Dunlop toroids, so I suspect that they're using toroids in these.
Anywho, I added an extra page to my doc looking at those two.
Stickman393
Well-known member
Couple recent additions:
I just got an older JEN Crybaby super. Its got one of the original red Fasel inductors, and the plastic cap was coming off a bit. So, I figured, let's take a look:
Yup, lo and behold, it is a 1408 pot core. Strange one: typical pot cores I see only have two openings. No indication to the grade of the ferrite, no markings whatsoever.
I added that one to my list. High Q, and it ranks amomgst the highest measured inductance values I've checked. And quite different than the white fasel in my first JEN.
Variation? Different materials? Hard to say. Only have a sample size of two.
I also included another recent acquisition: a shin-ei. Transformer-based wah. That one is *remarkably* unique. Its Q is flat across the frequency range, and it starts high and ends low.
I just got an older JEN Crybaby super. Its got one of the original red Fasel inductors, and the plastic cap was coming off a bit. So, I figured, let's take a look:
Yup, lo and behold, it is a 1408 pot core. Strange one: typical pot cores I see only have two openings. No indication to the grade of the ferrite, no markings whatsoever.
I added that one to my list. High Q, and it ranks amomgst the highest measured inductance values I've checked. And quite different than the white fasel in my first JEN.
Variation? Different materials? Hard to say. Only have a sample size of two.
I also included another recent acquisition: a shin-ei. Transformer-based wah. That one is *remarkably* unique. Its Q is flat across the frequency range, and it starts high and ends low.
Last edited:
Stickman393
Well-known member
Updates:
Snarling Dogs. Got me one of these novelty gas pedal monstrosities. It uses a toroid and it's fucking weird. Low Q, S curved inductance.
The circuit board is laid out for a transformer, not an inductor. I've read that on the earlier pedals they had to swap out a *ton* of those transformers cause of poor shielding and noise. I'm inclined to believe that they didn't give it much thought to be honest, from reading about that particular company.
On the horizon...two I just got today:
One is old. The other is new.
Snarling Dogs. Got me one of these novelty gas pedal monstrosities. It uses a toroid and it's fucking weird. Low Q, S curved inductance.
The circuit board is laid out for a transformer, not an inductor. I've read that on the earlier pedals they had to swap out a *ton* of those transformers cause of poor shielding and noise. I'm inclined to believe that they didn't give it much thought to be honest, from reading about that particular company.
On the horizon...two I just got today:
One is old. The other is new.
drgonzo1969
Well-known member
Sweet! I didn't know vintage Fender Fuzz Wahs came with detachable Star Wars landspeeders inside them. BONUS!!!
jessenator
Well-known member
Stickly-wan Kenobi be like
drgonzo1969
Well-known member
"These are not the toroids your looking for."
GAStan
Active member
On your automatic pot tester, what about using a digital encoder to determine shaft angle? An encoder puts out pulses as it rotates. Stepper motors with feedback use these for the feedback. Using one by itself may be easier to program (I'm not a programmer, just going on the theory of less moving parts). This would still require manually turning the pot but would take out virtually all shaft angle related error.
Stickman393
Well-known member
SOLID idea! In fact, it would probably take less overall work if I was to do away with the automation aspect.
All I would need is a voltage readout and an angle readout. I could input by hand.
Another option, for sure.
GAStan
Active member
Something like this is what i had in mind:
Rotary Encoder
Rotary Encoder
