Pickups with Air Coils

[Sweetfinger]

I've experimented quite a bit with pulling the poles, magnets, and keepers out of humbuckers for different sounds. You can certainly move towards a P-90 or single coil sound but the geometry of the coils locks you into a certain range. That second coil, though lacking its own set of poles, is still inside the flux of the other coil's field and does produce some signal.
It IS possible to get more of a P-90 sound out of that type of setup, but you have to wind your coils initially with that goal in mind. The Dimarzio Bluesbucker is essentially, a humbucker with just one coil magnetized but there are some subtleties to its construction. It isn't just a standard model with just one coil magnetized.
I've found that for the most part you will retain most of your hum rejection if you pull the poles or screws from a coil- enough that it isn't usually a problem. Designs that are engineered from the ground up can compensate.
Yanking screws out of humbuckers is one of the cheapest ways to get a "new" pickup or sound and it is reversible, so try and see what sticks!

[David Schwab]

The Dimarzio Bluesbucker is essentially, a humbucker with just one coil magnetized but there are some subtleties to its construction.

I hadn't see that one before. Have you examined one?

I'm guessing that the slug coil has extra slugs in it inserted from the bottom like their virtual PAF? Maybe a magnetic shield between the coils? Maybe the slug coil is wound lower and with heavier gauge wire? I'm basing those ideas on their Virtual Vintage patent.

This is pretty much what I made that I was referring to earlier in the thread. After examining a Virtual Vintage pro, I decided to experiment. I did it in a Strat type guitar with the dummy coil under the pickguard, but next to the active coil. It worked OK, but I have to tinker with it more, and I really didn't have time to mess with it. I used a slug coil from a humbucker that I rewound to about 2k.

[big_teee]

I tried pulling the screws.
Doing that, you still have one coil fed bottom up, and the other coil is RP fed top down.
With 4 wire hook up I could have changed the wiring of the removed coil, and fed both coils bottom up.
Would that sound more like a single coil, Perhaps?
I know there would be No hum cacel, but then the 2nd coil would be a continuation of the first.
That way you could run 8-9k, instead of just one coil of 4-4.5k with 42 approx.
T

[David Schwab]

I tried pulling the screws.
Doing that, you still have one coil fed bottom up, and the other coil is RP fed top down.
With 4 wire hook up I could have changed the wiring of the removed coil, and fed both coils bottom up.
Would that sound more like a single coil, Perhaps?
I know there would be No hum cacel, but then the 2nd coil would be a continuation of the first.
That way you could run 8-9k, instead of just one coil of 4-4.5k with 42 approx.
T

What do you mean "one coil fed bottom up, and the other coil is RP fed top down"?

If you pull out the screws, that coil wont sense the string very much, but the other coil will. If you want it to hum cancel, leave them wired the way they are.

If you want to make it more efficient, rig up the magnet some way so that the slug coil is not having the slugs charged by the magnet. One way to do that would be to use two narrow ceramic magnets charging the keeper on the screw coil, like a P-90, but not touching the slug coil.

Now mostly the screw coil will be sensing the strings, and the slug coil will mostly just be canceling hum.

If you want to try and do what DiMarzio does, wind the slug coil with something like 40 gauge wire, and don't wind as many turns as the screw coil. You probably also want to wind the screw coil with 43 gauge, and wind it hotter, since it will be the main signal producing coil.

Then sit at wait for Dimarzio's lawyers to call. (just kidding)

[big_teee]

What do you mean "one coil fed bottom up, and the other coil is RP fed top down"?

If you pull out the screws, that coil wont sense the string very much, but the other coil will. If you want it to hum cancel, leave them wired the way they are.

If you want to make it more efficient, rig up the magnet some way so that the slug coil is not having the slugs charged by the magnet. One way to do that would be to use two narrow ceramic magnets charging the keeper on the screw coil, like a P-90, but not touching the slug coil.

Now mostly the screw coil will be sensing the strings, and the slug coil will mostly just be canceling hum.

If you want to try and do what DiMarzio does, wind the slug coil with something like 40 gauge wire, and don't wind as many turns as the screw coil. You probably also want to wind the screw coil with 43 gauge, and wind it hotter, since it will be the main signal producing coil.

Then sit at wait for Dimarzio's lawyers to call. (just kidding)

Bad Choice of words.
I should have said Inside To Outside, then Outside to inside.
Or for you techs Start to finish finish to start.
I was thinking start to finish, then tie finish to start of the other coil.
That way both coils are same polarity, and the 2nd would be a contiuation of the first.
F Hum Canceling on this pickup!
T

[David Schwab]

Bad Choice of words.
I should have said Inside To Outside, then Outside to inside.
Or for you techs Start to finish finish to start.
I was thinking start to finish, then tie finish to start of the other coil.
That way both coils are same polarity, and the 2nd would be a contiuation of the first.
F Hum Canceling on this pickup!
T

If the two coils are the same polarity, then all you have is two single coils next to each other, and not a humbucker. In that case the second coil wont be doing much of anything.

[big_teee]

If the two coils are the same polarity, then all you have is two single coils next to each other, and not a humbucker. In that case the second coil wont be doing much of anything.

Wired in series in phase, what would I get?
Only one coil Magnetized.
T

[David Schwab]

Wired in series in phase, what would I get?
Only one coil Magnetized.
T

If they are in phase you wont have a humbucker, so then there is no use for the dummy coil.

Humbuckers are wired start-to-start or finish-to-finish.

[big_teee]

If they are in phase you wont have a humbucker, so then there is no use for the dummy coil.

Humbuckers are wired start-to-start or finish-to-finish.

You are missing the point!
But that is fine. Read the OP.
I've figured out this isn't going to meet my need, so I've Moved on!
T

[David Schwab]

You are missing the point!
But that is fine. Read the OP.
I've figured out this isn't going to meet my need, so I've Moved on!
T

I didn't miss the point. Why have a second coil that not's going to do anything? Just make a single coil.

The idea of one air coil would be to sound like a single coil and then cancel hum.

[salvarsan]

Are air coils suitable for air guitars?

[David Schwab]

Are air coils suitable for air guitars?

Only when played by air heads.