Stacked P90

[big_teee]

Looking for a patent for this, or detailed description.
If you have 2 P-90 coils stacked, how is the polarity, and where and how do the magnets work.
Not sure if with 2 stacked coils if the magnets go between the bobbins, or if the magnets would be against the screws at the bottom?
Several of us are trying to figure this out.

[copperheadroads]

It can only have 1 magnetic polarity
Like true p-90's
When magnets are opposing each other with only 1 magnetic field being created

[big_teee]

It can only have 1 magnetic polarity
Like true p-90's
When magnets are opposing each other with only 1 magnetic field being created

Where are the magnets, and what makes the coils out of phase.
I guess one is reverse wired?
If both are north and one is wired in reverse, will it be like a humbucker, or will the 2 coils cancel each other out?
A Patent to look at sure would be nice!
T

[Electricdaveyboy]

No Terry,
both coils wound in same direction and end of coils are soldered together.Just like a PAF.
The Top is south and the bottom south too.
Look at Lawrence stacked strat pickups made the same way but use a thin wire and ceramic magnets.

[big_teee]

No Terry,
both coils wound in same direction and end of coils are soldered together.Just like a PAF.
The Top is south and the bottom south too.
Look at Lawrence stacked strat pickups made the same way but use a thin wire and ceramic magnets.

So where are the magnets?
This one is not using rod magnets.
Bar magnets and screws
Thanks

[copperheadroads]

So where are the magnets?
This one is not using rod magnets.
Bar magnets and screws
Thanks

The magnets are touching pole pieces in the center ,Just like any p-90 ,In the Kinman pic you can see the corner of one of the bar magnets ,between the coils.
It don't necessarily have to be between the coils ,If the polepieces were protruding out the bottom of the coil the magnets would work there as well .like a MIM fender strat pup

[rhgwynn]

You need a frame with a center keeper-bar. The magnets lay on either side of the keeper.

-Rob

[David Schwab]

You can put the magnets right on the bottom as on a normal P-90. You will have to wind the pickup hotter than normal, because stacked pickups tend to be bright and lacking in low end.


I made a Stacked Tele pickup like that once. Wound it to about 13k, and it sounded like a lower wind pickup.

[big_teee]

You can put the magnets right on the bottom as on a normal P-90. You will have to wind the pickup hotter than normal, because stacked pickups tend to be bright and lacking in low end.


I made a Stacked Tele pickup like that once. Wound it to about 13k, and it sounded like a lower wind pickup.

David:
It looks like some are putting the bar magnets in between the bobbins like the Kinman.
That may be the best approach, I guess a guy could try them both places.
Once the bobbins are wound.
Thanks everyone, been getting some questions like this in the BC, trying to give informed answers.
Stacks, and Taps have been in the limelight lately.
T

[David Schwab]

You can do that too. Both ways work. The Fender SCN pickups have the magnets between the coils. One way doesn't work any differently than the other, in my experience anyway.

Remember that Kinman is doing some other stuff with his stacked pickups. The bottom coil is actually shielded from the magnets and is only for hum pickup. There's a steel plate between the top and bottom coil, and the top coil has the shield around it. He usually has laminated steel cores in the bottom coils to make them more sensitive to hum.

Here's his P-90.




Here's what he does with the Tele pickups:

More Information for Telecaster

[Electricdaveyboy]

No,
do not use rod magnets.They will give you top south and bottom north and will not work right.
I use the bar magnets between the top and bottom coil, magnets under the coil will not sound as good- think the magnets in the middle will shild the coils from each other.
Do not use the fat AWG 42, to wooly ( think:gibbo p-100 do not sound so great ;-))go for something like 44 and use ceramics or A8 and you may be halfway there.For more bottom you can use iron slugs instead of screws.

[Mike Sulzer]

Looking for a patent for this, or detailed description.
If you have 2 P-90 coils stacked, how is the polarity, and where and how do the magnets work.
Not sure if with 2 stacked coils if the magnets go between the bobbins, or if the magnets would be against the screws at the bottom?
Several of us are trying to figure this out.

If you put the magnets below both coils, you get less field strength at the strings. You do not need any permanent field through the bottom coil, but it does not hurt, either, no matter what the polarity. (Think of it as a dummy coil placed very close to the pickup.) To reverse the electrical polarity, you could reverse wind (or turn one coil over) or just reverse leads. Might be some very subtle differences.

Putting the magnets between the bobbins gets the lower coil further down, which means its gets less signal, and so less of the signal cancels with the signal in the main coil. The hum still cancels fine.

[David Schwab]

No, do not use rod magnets.They will give you top south and bottom north and will not work right.

Sure it will. Most stacked pickups are made that way.

[copperheadroads]

I've made a few sets of stack strat pups with long alnico rods , & a couple with blades

[Electricdaveyboy]

Sure it will. Most stacked pickups are made that way.

.. yes they are but sound like shi... 99 percent of the time.I had pretty good results with rods and ceramics between the coils and I did a lot of experiments.Did around 200 hundered of stacked strat pickups this way and I am nearly sold out on them.