Do different parts of the coil pick up different tones?

[mcgruff]

Got some wire in the post and about to start another round of winding experiments (some humbuckers for a 335-style guitar).

It occurred to me that if different parts of the coil pickup different balances of frequencies, this might be used to manipulate the pickup's tone. Different wire gauges or single/double-coated wire of the same gauge could be used in different regions of the coil. Winding pattern and tension could be used to lay down a little more wire in some regions and a little less in others.

So are there any significant tonal gradients in a coil:

(1) from inside to outside laterally

(2) from top to bottom vertically

For example, maybe there's a region which is really important for treble, and another which has more influence on bass response, and so on?

[big_teee]

Listed is some things that effect your tone in a Humbucker.
TPL 60-85, and the accepted practice is no scatter.
Winding height is small 1/4- 5/16", not allowing much variation in winding pattern and tpl.
Medium tension.
Other than that, IMO just wind the pickup.
The biggest variations in tone.
1. Wire size
2. Type of steel used in Keeper, screws, and slugs.
3. Type of Baseplate used, Nicel Silver is most used, and is bright. brass is darker, and forbon non metallic is probably the brightest.
4. TPL and Tension, and amount of turns.
5. Bobbin wire area Diameter. The larger the diameter across the wound coil, the darker the tone.
6. Equal or non Equal coils.
7. With unequal coils, experiment with which coil is fed first.
8. Magnet type used, Different Alnico grades, Ceramic, and possibly NEO.
9. Bobbin height effects tone greatly, but is not adjustable in Humbucker bobbins, like in Single Coils.
10. In the Guitar, the Pot, and Cap Size, effect tone greatly.
That is about all I can think of at the moment!
If you come up other variations, please list them here.

[J M Fahey]

Got some wire in the post and about to start another round of winding experiments (some humbuckers for a 335-style guitar).

It occurred to me that if different parts of the coil pickup different balances of frequencies, this might be used to manipulate the pickup's tone. Different wire gauges or single/double-coated wire of the same gauge could be used in different regions of the coil. Winding pattern and tension could be used to lay down a little more wire in some regions and a little less in others.

So are there any significant tonal gradients in a coil:

(1) from inside to outside laterally

(2) from top to bottom vertically

For example, maybe there's a region which is really important for treble, and another which has more influence on bass response, and so on?

No.

The coil has a core, usually some kind of iron but this applies even if it's air cored, and any magnetic flux variation inside that core will induce a proportional voltage in any and all wires surrounding it.

There is no frequency selective process there whatsoever.

[bbsailor]

Got some wire in the post and about to start another round of winding experiments (some humbuckers for a 335-style guitar).

It occurred to me that if different parts of the coil pickup different balances of frequencies, this might be used to manipulate the pickup's tone. Different wire gauges or single/double-coated wire of the same gauge could be used in different regions of the coil. Winding pattern and tension could be used to lay down a little more wire in some regions and a little less in others.

So are there any significant tonal gradients in a coil:

(1) from inside to outside laterally

(2) from top to bottom vertically

For example, maybe there's a region which is really important for treble, and another which has more influence on bass response, and so on?

mcgruff,

Maybe not tone differences but measureable volume differences.

Zone2 Zone1 IMAGI Zone1 Zone2
Zone4 Zone3 IMAGI Zone3 Zone4

See my crude attempt to depict a side view of a mangetic cored bobbon with 4 Zones of wire. Wire in Zones 1 and 2 are typical of a P90 or Wide Fender SC pickup. Wire in Zones 1 and 3 are typical of a tall, thin pickup like a Fender Telecaster. Typically Zones 1 and 3 are close to the magnet and put out more voltage than the same number of turns wound farther out in Zones 2 and 4. However the closer the coil is to the strings will tend to increase the output so Zones 1 and 2 will be louder than wire located in Zones 3 and 4. How the magnetic field is focused or spread will dictate where or in which Zones the wire should be placed to optimize the output.

Joseph Rogowski

[big_teee]

mcgruff,

Maybe not tone differences but measureable volume differences.

Zone2 Zone1 IMAGI Zone1 Zone2
Zone4 Zone3 IMAGI Zone3 Zone4

See my crude attempt to depict a side view of a mangetic cored bobbon with 4 Zones of wire. Wire in Zones 1 and 2 are typical of a P90 or Wide Fender SC pickup. Wire in Zones 1 and 3 are typical of a tall, thin pickup like a Fender Telecaster. Typically Zones 1 and 3 are close to the magnet and put out more voltage than the same number of turns wound farther out in Zones 2 and 4. However the closer the coil is to the strings will tend to increase the output so Zones 1 and 2 will be louder than wire located in Zones 3 and 4. How the magnetic field is focused or spread will dictate where or in which Zones the wire should be placed to optimize the output.

Joseph Rogowski

Didn't get the images, and the zone winding?
Is all that practical on a humbucker that is barely over 1/4" bobbin winding height?

[David Schwab]

(2) from top to bottom vertically

I think it would be very hard to tell on a continuous coil, however, I have experimented with stacked single coil size pickups. These had the magnets on the bottom like a P-90, and a steel blade extending through both coils. I wired the two coils up to 4-conductor cable, so I was able to turn each coil on and off.

The bottom coil was very mellow sounding, with a lot less highs than the top coil. Both coils were wound the same. The pickup was the height of a typical single coil. This is probably because the coil was farther from the strings, even though the blade was close to the strings. The top coil sounded as you would expect.

We know that wide squat pickups sound different from tall thin pickups, so I'd be curious to do the same thing with coaxial coils, and listen to the inside and output coils to see. I'd bet the output coil would likewise be more mellow sounding.

[David Schwab]

No.

The coil has a core, usually some kind of iron but this applies even if it's air cored.

Air cores have no iron in the core. Just air. Did you mean a bobbin-less coil?

[mcgruff]

Thanks everyone for the advice.

@David Schwab: I'll maybe try an experiment with four coils on one bobbin - top inner, top outer, bottom inner, bottom outer - just to see what happens.

[David Schwab]

My guess is that inner/top coils will be the brightest. Let us know what you find!

[big_teee]

I did the Stacked Pickup project on here a while back.
I stacked two humbucker bobbins, and put rod magnets through both coils.
It turned out to be important to feed the top coil, because if you fed the bottom coil first it was weaker and muffled.
The bottom coil ended up just used to hum cancel.
It was just as loud if you split and just used the top coil, but then no hum canceling effect.
I thought the OP was wanting to know how to get coil position changes all on one humbucker coil.
If your talking about different separated areas then they should sound different.
T

[mcgruff]

Yeah - the latter. I'm probably not explaining myself very well. If there are tonal gradients to exploit, you could build a coil with several discrete winds. Say you start with a top inner coil (with some kind of partition to keep the bottom half clear). Next you'd wind a bottom inner coil, then a top outer and a bottom outer. All four would be connected up as one big coil but, because they've been wound separately, you'd have the opportunity to vary how you wind different regions. That might let you manipulate different tonal properties for the final, blended sound.

[David Schwab]

It turned out to be important to feed the top coil, because if you fed the bottom coil first it was weaker and muffled.

What do you mean by "feed"? Do you mean you had one end of the top coil to hot and one end of the bottom coil to ground?

It shouldn't matter though, since the signal is going through both coils anyway. So it's the same as with a regular single coil having a top and bottom.

The thing with the stacked humbuckers is they have a lot of low end cancelation, so they tend to be kind of thin, and very bright sounding. This is why they are usually wound pretty hot.

Also, you can reverse the polarity of the two coils, so that they are in phase, and then you just have a loud single coil.