Inductor's Role in Tone?

[cmat]

I have 2 wahs now each has the same mods one is a Vox V847 and one is a Cry baby.  I built the GGG board for the crybaby with a Yellow Fasel which is the same as a V847 board.  I built the Vox with the stock inductor.  The Vox inductor measures 534 mH and the Yellow measures 624.  My Vox sounds much better than the crybaby but I didnt measure the transistors but both have mpsa18's.  I have heard of fasels measuring between 150 something and 650 something.  I want to know if any one can tell me what audible diffrence there is in an inductor that is 500mH and one that is 150mH or 650mH.   Also what inductors with the same measurments have you tried and prefered in the same peda?  I hope to hear alot of answers on this.  Thanks!

[aron]

What I have found is that the Fasel's can alter the tone of the wah, but the wah has to be fine to begin with. As per R.G.'s article about wahs, there are many parameters that affect the tone of a wah, the inductor being only one of them. As for the Fasels being all over the place, I have only read it once and that was from someone that sells their own inductor. I'm not saying it's not true, all I am saying is that is where I read it.

[cmat]

I believe it was the guy from ArielFX who said that.  I would like to know what diffrence ,if any, the same inductor in the same circuit but with diffrent measurment would make.  I dont think a 400mH yellow Fasel is going to make much, if any. diffrence in tone over a yellow Fasel that measures 650mH.  I dont have a bunch of inductors to try and see but I know someone will know.  I dont think a 500mH inductor is the be all end all that some make it to be.  I guess I am taking the long way around about this.    

[Mike Burgundy]

Also from RG's article, one can conclude the exact value doesn't matter all that much - stick it in and tune the filter cap to taste. BUT: there may be inductors that include some harmonics all of their own which have an audible impact. This is beyond an "ideal" inductor though.

[R.G.]

The inductance value in henries changes the resonance point by the square root of the change in value. That is, if you halve the inductance, the resonance point goes down to a frequency 0.7071 times where it was, for the same resonance capacitance.

The inductor may tend to saturate more or less depending on the inductance value. Here's how that works. I suspect that the observed variation in the inductances may be dependent on how good a fit the core halves have. For best inductance, the mating surfaces have to be mirror smooth and in perfect contact. If they don't fit well, that introduces an air gap (or dirt gap!) that lowers the inductance. That's a more subtle and less observable thing than missing the number of turns, which are all done by machine counter anyway. Low inductance could be correlated with poor fit of the core halves. This would lead to a less-saturable inductance and therefore fewer distortion harmonics. It's a guess about one way that you could get more or less harmonics.

[cmat]

So an inductor that has more inductance is more desireable than one with less.  For example a 600mH would be more desireable than one that is 400mH granted both are the same inductor such as yellow fasel?

[Paul Marossy]

What I have found is that the Fasel's can alter the tone of the wah, but the wah has to be fine to begin with. As per R.G.'s article about wahs, there are many parameters that affect the tone of a wah, the inductor being only one of them.

This is my experience, too.

Also from RG's article, one can conclude the exact value doesn't matter all that much - stick it in and tune the filter cap to taste. BUT: there may be inductors that include some harmonics all of their own which have an audible impact. This is beyond an "ideal" inductor though.

That's a good point. The real purpose of the inductor, according to the patent documentation, is to provide a complimentary reactance as well as making it a resonant circuit. A difference of 100mH one way or the other isn't going to affect the sound radically.

The inductance value in henries changes the resonance point by the square root of the change in value. That is, if you halve the inductance, the resonance point goes down to a frequency 0.7071 times where it was, for the same resonance capacitance.

The inductor may tend to saturate more or less depending on the inductance value. Here's how that works. I suspect that the observed variation in the inductances may be dependent on how good a fit the core halves have. For best inductance, the mating surfaces have to be mirror smooth and in perfect contact. If they don't fit well, that introduces an air gap (or dirt gap!) that lowers the inductance. That's a more subtle and less observable thing than missing the number of turns, which are all done by machine counter anyway. Low inductance could be correlated with poor fit of the core halves. This would lead to a less-saturable inductance and therefore fewer distortion harmonics. It's a guess about one way that you could get more or less harmonics.

Interesting. So, it sounds like the biggest factor in the "sound of an inductor" comes down to manufacturing consistency! Which seems to be evident in what I have heard about the reissue Fasels.

So an inductor that has more inductance is more desireable than one with less.  For example a 600mH would be more desireable than one that is

I do know that closer to 600mH is better than say 300mH. The 600mH inductor will sound "fatter" because it is letting more of the low mids/bass thru. A 300mH inductor is going to sound more nasally. The Vox grey wah pedal that Jimmy Page used a lot had a 250-300mH inductor in it...

EDIT: I forgot to mention that the vast majority of people seem to like an inductor that's as close to 500mH as possible. Closer to or over 600mH and some people feel it's "too muddy". That could be compensated for by tweaking the sweep cap some...

[formerMember1]

INductors have a huge role in tone.

I have A/Bed a Castledine, ArielFx, and Fulltone Halo.

They all sound VERY different!!

the Castledine, was sublte, a little dull, and not much vocal to it.
The Fulltone was thin, but tight and treble bunched up at end of pedal throw.
The areilfx was more midrangy and vocal, and had nice bass to it.  By far the best indcutor i ever tried and that includes all of them except a yellow fasel,(i tried dunlop and red fasels also)

I tried everything with the fulltone pot and propot,  by far the propot is most like an original ICAR, the fulltone was too quacky and short, and not good treble to it.

I guess it is subjective, but i do hear a major difference in halo indutors and other inductors.

I also tried  changing the 4.7(4.0uf) cap to a 15uf, and there is a noticable difference there.  I am gonna try a 4.0uf and 10uf when i get them off mouser.

the 15uf was more vox clyde like, It sounded like the Q/resistor was changed when swapping this cap.

Again i know it is subjective, and my hearing is NOT psychological either,  I recorded the clips numerous times, and always heard a difference except a few times with the 4.7uf cap swap, because i was using it with a fuzzface,  it wasn't as distinct of a difference.

BUT clean it is a nice difference.




PS:same say it could be inductor tolerances also, but i thought the whole point of getting a halo repro, was being able to get the 500mh,

[RDV]

I've been thinking about ordering a couple of the 470h indutors that Mouser sells for like 2 or 3 bucks and see if it's worth all that extra money for the Fasels and Fultones and what-not. If and when I do I'll report my results.

RDV

[markphaser]

 The metal Can wah inductor has a different tone i think the metal can creates different flux/magnetic permeability because its a inductor with a metal can around it.

Does the inductor in a wah expand? like induced currents or voltages?
the rate of the expansion

Does the inductor in a wha have Discharging and Charging curves?

[Paul Marossy]

INductors have a huge role in tone.

I have A/Bed a Castledine, ArielFx, and Fulltone Halo.

They all sound VERY different!!

Maybe. In the older wahs, it's almost a case-by-case thing dues to the tolerances of the parts and what specific types of parts were used. All I was trying to say originally is that changing the inductor in your wah isn't going to turn it into another wah pedal. Just putting a Fasel inductor in a wah isn't going to turn it into a Clde McCoy or whatever. Anyway, I bet it has more to do with how they are manufactured more than who manufactured them. I'm not an expert on inductors, but I have a suspicion that the physical shape and method of construction has a lot to do with how it behaves in a resonant circuit - more so than an exact value of 500mH does. 

[Stevo]

If you have a good sounding wah to begin with but want to make it better....I would say the Halo inductor from Arielfx.com is really going to suprise you with a quality sounding, bassier and more vocal as well as not tingy highs to it!!.....I couldnt believe the difference when I did the volume boost mod.... and a halo inductor from arielfx.....but like I said it was a good sounding vox wah847 to begin with!!!!

[formerMember1]

Maybe. In the older wahs, it's almost a case-by-case thing dues to the tolerances of the parts and what specific types of parts were used. All I was trying to say originally is that changing the inductor in your wah isn't going to turn it into another wah pedal. Just putting a Fasel inductor in a wah isn't going to turn it into a Clde McCoy or whatever. Anyway, I bet it has more to do with how they are manufactured more than who manufactured them. I'm not an expert on inductors, but I have a suspicion that the physical shape and method of construction has a lot to do with how it behaves in a resonant circuit - more so than an exact value of 500mH does. 

Paul, i didn't mean anything against your post at all, i actually didn't even read the whole thread, just saw it from another thread that you posted the link to this thread, and i just did that A/B testing yestearday, and i stuck it in the thread for others to read, i was in a hurry, and didn't have achance to read your post.

BUt i think you are right on target. 

EDIT**
but i think the main thing is, a good wah circuit will not sound good with a "bad" inductor, but a bad wah circuit won't sound "great" with a "good" inductor,

I think everything has to add up to be great, not just one component. 

The caps definitely make a difference and also the inductor and pot, and these being different material etc,..are what makes a clyde mccoy a clyde mccoy and a crybaby a crybaby, etc,...

[Paul Marossy]

Paul, i didn't mean anything against your post at all, i actually didn't even read the whole thread, just saw it from another thread that you posted the link to this thread, and i just did that A/B testing yestearday, and i stuck it in the thread for others to read, i was in a hurry, and didn't have achance to read your post.

No worries. 

but i think the main thing is, a good wah circuit will not sound good with a "bad" inductor, but a bad wah circuit won't sound "great" with a "good" inductor,

I think everything has to add up to be great, not just one component.

Agreed! 

The caps definitely make a difference and also the inductor and pot, and these being different material etc,..are what makes a clyde mccoy a clyde mccoy and a crybaby a crybaby, etc,...

Yep, you have to look at the total package. That's what I'm getting at.

[markphaser]

I seen Silver caps with a red line across them i think they were paper caps im not sure in old vox wahs
these silver caps with a red line who made them? because i think the silver caps made a big difference

[formerMember1]

No worries.

Mark Phaser:

there is a thread around here where Mr Geoffrey Teese, says that those caps are mylar i think.  I think Mouser carries them, under the Vishay/Rhoederstein name,  ( i have some on order from Mouser)

You could use Polyester Metallized Film, Mylar, Polypropylene, Polycarbonate(though scarce and obsolete), polystyrene(might not possibly sound good here though), for the .22uf caps.

You could use Polypropylene or Polystyrene for the .01uf caps.   (i tried polyester film, Mylar for .01ufs but didn't like it)

Believe it or not, i have a $150.00 dollar order to Mouser, which 1/2 of it, is in caps and other parts for the wah to try for A/B ing, i am trying virtually every type, material, and manufacter of caps for the wah.
Not a loss either, because the "unused" caps will go in future wah builds, and/or other pedals, 

[markphaser]

The silver caps with the red strips were mylar? because when i felt them they felt like paper in the old voxs
maybe the brands and manufacters make a difference

I think the silver caps with the red strips were not in the feedback path 

[formerMember1]

i could be wrong, but that is what i read on the forum,...

I don't think they were paper but i could still be wrong,

I would think they were a wrap and fill variety, close to Tropical fish polyester metalized film,  but i could be wrong on that,

[Paul Marossy]

OK, so I've been thinking. I have always been under the impression that the higher the inductance of the inductor, the more muddy it got. But, according to RG, as you go down in size, the frequency range gets shifted down, not up. And I have heard that the old Vox grey wah that Jimmy Page used had inductors in the 250-300mH range. And, the Vox grey wahs also apparently have much more of a "deep midrange tone".

So then, if one wanted to have more "grunt" and bass, then one should try a 300mH inductor instead of the 500mH one. Am I correct in this? If so, then my next question is where the heck can you get a 300mH inductor?!

RG? Anyone?

[lovric]

I have made wah from an old vol pedal. First it had 420uH inductor. It sounded like a treble pot. There was some aid in enlarging the cap that goes from the second transistor's emitter back to inductor, but it became a proper wah only with the 570uH inductor. And that goes along with the preaching of the Holy Technology of Wah-wahs. there.