Go tall!

[Possum]

well yeh...

yes magnet height is a design factor in tone. well sort of, what you are really doing is making the COIL taller by doing that, a taller coil is brighter because there's less wire wrapped around itself. Use short magnets and you get more midrange. Staggered sets have an interesting magnetic phasing thing going on thats another factor. I have a customer who's kind of driven me nuts doing all these custom staggers as experiments, interesting stuff, interesting results.

[NightWinder]

Are you spanking him with a good bill? Times money. I got a customer like that. A few. Always sending me other peoples stuff? "Here, make this the same, but your way?" Like total bullshit. He's a really nice guy, but does'nt understand everyone winds and sounds different. Annoys me to no end man. Most are from over seas. This I don't understand. Must be too much money or something.

[Zhangliqun]

Taller means a narrower coil which doesn't see as long a piece of string and therefore doesn't pick up as much of the longer wavelengths of the lower freqs -- and is therefore brighter.

[David Schwab]

Taller means a narrower coil which doesn't see as long a piece of string and therefore doesn't pick up as much of the longer wavelengths of the lower freqs -- and is therefore brighter.

That's one reason.. the aperture is narrower. But I think there's several things going on... like Dave said, the wire doesn't wrap over itself as much, and with a squat wide coil, the outer wraps are father away from the core/magnet. With a taller coil, the bottom of the coil is farther away from the strings. I was surprised that when I listened to the bottom, vs. the top coil in my Tele stack, how different they sounded. The bottom coil was very mellow sounding... more lows and less top end. Also with taller magnets/poles, you have more core material, so the inductance would be higher.

It's all very intertwined!

[rocket]

Actuallly I think the inductance gets smaller, the longer the coil is, (with equal number of windings and diameter of the coil) after all a pickup is mostly an inductor.

L = µ*N^2*A/l

[Joe Gwinn]

Actuallly I think the inductance gets smaller, the longer the coil is, (with equal number of windings and diameter of the coil) after all a pickup is mostly an inductor.

L = µ*N^2*A/l

This is the formula for a long single-layer solenoid with more or less circular turns, where "long" means length at least five or ten times the diameter, and "more or less circular" would include a single square core, but does not include the typical pickup, where the "core" is lery long and thin. Pickups are neither long nor round in cross-section, so, while this formula is good for getting the lay of the land (what I call a "scaling law"), don't be surprised if it isn't very accurate at predicting the actual inductance.

There are more accurate formulas, but they get pretty complex pretty fast.

Perhaps the most expedient thing to do is to make up a test coil (bobbin and wire, no magnets or cores), compute the inductance from the turns count, length (along the axis of the poles), and the area of an average turn.

Then, measure the inductance, and compute the ratio of measured to predicted. So long as the size and shape of the coil don't change too much, this ratio can be used to correct the prediction of the long solenoid formula to yield a reasonable estimate of the inductance.

The most comprehensive book availabe on calculation of inductance is "Inductance Calculations", Frederick W. Grover, Dover 2004, originally copyrighted in 1946 and 1973, 286 pages. This is not at all an easy book. It's all there, but not in a form that one can go to page <whatever> and just use the formula.

[black_labb]

im thinking of making a very bright, almost harsh sounding single coil by using a plate of steel as opposed to individual pole pieces and magnetising it from a ceramic magnet at the bottom. id make it fairly tall aswell. id like to see how disgustingly sharp a sound i can make and see what i could do with it. id put it at the bridge and make a neck join on the guitar in a way that the harmonics are fairly strong. make for an interesting experement.

[rocket]

the scaling law thing was what my posting was about , mainly.

longer --> smaller inductance (Strat)
bigger crosssection --> (Jazzmaster)

Of course that's just a tendency and in turn the shape of the coil also will change the capacity.

[Joe Gwinn]

the scaling law thing was what my posting was about , mainly.

longer --> smaller inductance (Strat)
bigger crosssection --> (Jazzmaster)

OK. I just wanted people to know just how far they could push the formula.

Of course that's just a tendency and in turn the shape of the coil also will change the capacity.

True, but I don't think changes in self-capacitance are all that important in practice, as the coil capacitance is generally swamped by the capacitance of the cable from guitar to amp.

[David Schwab]

im thinking of making a very bright, almost harsh sounding single coil by using a plate of steel as opposed to individual pole pieces and magnetising it from a ceramic magnet at the bottom.

It wont be all that bright as you might think! The steel can muddy it up fast. The steel gives you a lot of inductance. With fewer turns it would be bright. Or use laminated steel.

id make it fairly tall aswell. id like to see how disgustingly sharp a sound i can make and see what i could do with it. id put it at the bridge and make a neck join on the guitar in a way that the harmonics are fairly strong. make for an interesting experement.

Here's a Tele pickup made like this... two ceramic mags on the base of the steel blade in the same manner as a P-90. Wound with 43 ga wire.

It's quite full sounding, and has a bit too much bottom. It's actually a stacked pickup... but when run inphase it's very loud and bassy. In hum canceling mode it's super Tele bright.

[black_labb]

It wont be all that bright as you might think! The steel can muddy it up fast. The steel gives you a lot of inductance. With fewer turns it would be bright. Or use laminated steel.



Here's a Tele pickup made like this... two ceramic mags on the base of the steel blade in the same manner as a P-90. Wound with 43 ga wire.

It's quite full sounding, and has a bit too much bottom. It's actually a stacked pickup... but when run inphase it's very loud and bassy. In hum canceling mode it's super Tele bright.

thanks for that, its good to see what people with more experience do to quicken my learning.

[David Schwab]

thanks for that, its good to see what people with more experience do to quicken my learning.

There's a lot more people here with more experience winding than me... But it only takes one try to confirm what something sounds like. I actually didn't know how that pickup would sound, and when I get more time I plan on trying some more ideas with it.

It's important to read a lot, and then try out those things you learned and see what they sound like.

[madialex]

Understood, one and all. Just so you know, I was aware this had been done for awhile and wasn't trying to attribute this to Dan and Stew-Mac as an innovation. It was simply an article that people (beginners especially) could look at. It's also the case that sometimes things you already know about get taken for granted, treated as a given and overlooked for that very reason. Once in a while reminding people about the obvious isn't such a bad thing to do.

We've seen threads/comments in the recent past about polepiece diameter varied across pickup positions. Given Possum's post above, are taller and shorter coils/polepieces a smart idea for tailoring neck/middle/bridge tonal response?

Actually Thank you for bringing it up, I had forgot all about that idea and was trying to figure a way to get lots more power from a tele neck pickup and added clarity, See my other thread about tele neck pickups. I think i'll build one tomorrow if I have time and see what happens. I have other work pressing but I wont forget that idea though.

[black_labb]

It wont be all that bright as you might think! The steel can muddy it up fast. The steel gives you a lot of inductance. With fewer turns it would be bright. Or use laminated steel.

is it the volume of the steel, or its surface area? i was thinking that by using a thin sheet (obviously thick enough to have some stiffness when wound) it would not have too much metal. the thought was that the extra clarity from such a thin pickup would allow for more windings without it getting muddy, possibly giving a different sounding pickup. maybe, as you say, an extremely thin piece laminated for stiffness. im only playing with the idea, and at the moment im just making pretty normal pickups. just wound some that came to 6.49 ohms, they are similar to p90's but instead of 2 magnets either side, its 2 bar magnets underneath. i will see how well it works

[David Schwab]

is it the volume of the steel, or its surface area? i was thinking that by using a thin sheet (obviously thick enough to have some stiffness when wound) it would not have too much metal. the thought was that the extra clarity from such a thin pickup would allow for more windings without it getting muddy, possibly giving a different sounding pickup. maybe, as you say, an extremely thin piece laminated for stiffness. im only playing with the idea, and at the moment im just making pretty normal pickups. just wound some that came to 6.49 ohms, they are similar to p90's but instead of 2 magnets either side, its 2 bar magnets underneath. i will see how well it works

Thin steel is better than thick for retaining highs. Laminated steel is several thin layers glued together, and the layers do not touch each other... they are insulated from one another. This is to help eliminate eddy currents.

You can also cut slots in the bar. This breaks up the contiguous surface area and breaks up the eddies.

Winding on the low side like that will let you get good high end. The inductance becomes and issue when you wind a lot of wire.

Having said that, I did a 14.4K, 3.75" wide humbucker for a 9 string guitar wound with 43 ga. It had dual 1/8" steel rails, and a 2" X .75" X 3/16" ceramic magnet. It got a decent top end, and actually sounded kind of Stratty when wired in parallel.