For the EE and science guys AQ

[23]

Heres my question

What is the difference in the red fasel, yellow fasel, halo, and stack o dimes internally, in construction ,and in measurement?

I have become interested in winding inductors and this is something I cant find info one, besides core cup or torroidal (?) and that halos are all held together with a clip thats a ring on top.


thanks to anyone that knows this stuff and takes the time to explain you have my respect,

sands

[23]

So no one can give any insight even to what the differences are between a torrodial or cup core. I kno most are wound on ferrite right? So what is Epcos that all of these kits are using? thanks             sands

[panterafanatic]

Small bear sells some pot core inductor kits for wahs, I've bought multiple and they've all been great. The main difference is the inductance per size, pot core and toroidal give large inductances for a smaller space but are hard to tune to a specific inductance, this is of little concern, as long as you're close, you'll be in good shape. The difference between the Red and Yellow is probably the inductance, and possibly the gauge of the wire used to wind them. The inductor kits from SBE really are fantastic, mine was a little more noisy than the red I took from my crybaby but had a nicer tone.

[23]

Thanks for the reply........ Im probally going to get one of his kits and I got to get a LCR meter but Im really interested in what seperates the inductors especially core and winding wise I mean the list is forever and what is the difference, TDk, fasels, SoD, halo, film can, EL RAD, the new type with the screw through them? IF the measure inductance and resistance is similar then it has to be core, wire and winding that cause the different sounds.

thanks sands

[new]

This is the result from my measurment.
Red Fasel  537 mH  /16.7 Ω
Yellow Fasel  628 mH  /18.2 Ω

[R.G.]

The bottom line with magnetics is that everything matters. Everything, even including anything just NEAR the coil.

- the exact placement of every wire in every turn on the coil
- the wire gauge affects both resistance and internal distributed capacitance
- the core material and its resistivity, permeability, gap between parts, as well as it saturation characteristic; the size of the particles in ferrite, and spacing between them matter.
- the shape of the core, including not only its cross sectional area but also how well it folds up the magnetic field
- if the core leaks any magnetic field - and they all do - then any magnetic or diamagnetic material near the core changes the inductance
- the core's magnetic *history* matters
- screws, adjusters, fillers, etc. in the gap of the core matter

Back at your particular question, toroids are theoretically un gapped, while cup/pot cores have to have a gap to get the coil inside. However, all ferrites are made of small particles sintered together. Each particle is isolated from the others to give high resistivity and low core loss, but that same isolation means that they are magnetically isolated, too, and so a toroid has a distributed gap and leaks field from everywhere. The pot/cup core leaks more from the even-more-abrupt gap.

Compared to electrical flow and fields, there are no magnetic insulators except superconductors. Leaving those outside the realm of wah pedals, ferrite "conducts" magnetic field/flow only about 3000 times as well as free space. Transformer iron is only about 10,000 times as good as free space. On the other hand, free space resists electrical flow a relatively infinite amount, so there exist electrical insulators. Magnetic fields always leak, and so everything near the generator gets some M-field and correspondingly changes what is happening back in the coil.

About all you can do is talk about how big the relative contributors are, and so what to ignore as a simplification. Talk to a pickup maker for more of this. Everything matters there, as well.

[23]

Thanks RG, ive read your wah page about 20 x or so. IF magnets make the old inductors sound so good, Ive read here and there, then why hasnt someone actually tried to wrap an inductor with a magnet?

I realize the sum of the parts make the whole and that wraping inductor at home would be alot of trial and error. Thanks again.

sands

[R.G.]

Thanks RG, ive read your wah page about 20 x or so. IF magnets make the old inductors sound so good, Ive read here and there, then why hasnt someone actually tried to wrap an inductor with a magnet?

It's not just that magnets make old inductors sound good - that's an oversimplification. There is a specific, tiny amount of magnetic offset in some of the old, high-mojo inductors that can add a certain something to the sound. Too much magnetic field is as bad or worse than none at all.

People have experimented with sticking a small magnet onto a wah inductor to put in a little bit, and they seem to be able to get it set up in ways that make them happy with the sound. But winding directly onto a ferrite magnet would likely cause other issues.