"Tri-coil" humbucker?

[Stilts]

Hi all,

I've got an idea in mind for bass humbucker, but I'm not sure how viable it is. I want something that I can wire up with a series/single coil/parallel switch, so I thought of having a standard coil neck-side and a split coil on the bridge side to reduce hum when selected in single coil mode.
Is there a way I can wire this to suit the switching I want?
Or will I run into some issues there and should I just stick with a boring old dual coil?

Thanks

[Mike Sulzer]

In single coil mode the two "split coils" must be wired so that they are electrically out of phase in order to cancel hum. Wired this way, they cannot provide the hum to cancel that from the other coil when in the humbucker mode. When switching modes, you could switch the phase of the two split coils. In order for all the signals to add in the humbucker mode, all magnets in the split coils must have the same polarity. This means that in the split coil mode, the signal polarities will be be different for the two sets of strings. This might be an issue for some.

Hi all,

I've got an idea in mind for bass humbucker, but I'm not sure how viable it is. I want something that I can wire up with a series/single coil/parallel switch, so I thought of having a standard coil neck-side and a split coil on the bridge side to reduce hum when selected in single coil mode.
Is there a way I can wire this to suit the switching I want?
Or will I run into some issues there and should I just stick with a boring old dual coil?

Thanks

[big_teee]

You could wire the three coils to a switch where they are not all active at one time.
Play two coils in series in canceling mode, then split those two coils and add the third in canceling mode.
I do that with a Strat.
I use a humbucker in neck and bridge and a SC in the middle.
When Split, the three pickups act like a normal strat with RWRP in the middle.
Hum canceling in position 2 & 4.
T

[dwmorrin]

Are you just asking how to wire a humbucking pickup for series/parallel/split? A DPDT switch is all you need, and the wiring diagram can be found here: Wiring Diagram

If you have a humbucker that bucks in series, then it should also buck in parallel... so with series/parallel you have 2 different output levels and tones, both hum canceling.

You say you want to reduce hum when in single coil mode. If you add in another coil, you won't be in a true "single coil" mode, but rather doing some sort of dual coil combination. You can do split coil, or dummy coil to keep the tone away from regular humbucker territory - but this is a giant topic in itself.
I think the tri-coil idea is interesting, but I'm not sure how much more satisfied you'll be over the "boring old dual coil."

[Mike Sulzer]

I guess Stilts will have to clarify what he means, but to me it looks like he wants a humbucker with a normal coil on the neck side, and a coil split in two on the bridge side, kind of like the usual split coil used on the basses to cancel hum, but maybe avoiding the offset. The question is how to wire and switch it so that it cancels hum when used "sc" or "hb" and gets the signal right in all modes.

Are you just asking how to wire a humbucking pickup for series/parallel/split? A DPDT switch is all you need, and the wiring diagram can be found here: Wiring Diagram

If you have a humbucker that bucks in series, then it should also buck in parallel... so with series/parallel you have 2 different output levels and tones, both hum canceling.

You say you want to reduce hum when in single coil mode. If you add in another coil, you won't be in a true "single coil" mode, but rather doing some sort of dual coil combination. You can do split coil, or dummy coil to keep the tone away from regular humbucker territory - but this is a giant topic in itself.
I think the tri-coil idea is interesting, but I'm not sure how much more satisfied you'll be over the "boring old dual coil."

[big_teee]

Are we talking three coils, or just two.
If you split to just one coil it will not be hum free, unless you have the other coil somewhere.
The title was Tri-coil, but in his post, I only count 2.
T

[SpareRibs]

Hello,
Isn't there a humbucker already (or in days gone by) on the market with 3 coils ?

[Mike Sulzer]

I think we are talking about taking one coil of a humbucker and replacing it with two, each covering two of the four strings of the bass.

Are we talking three coils, or just two.
If you split to just one coil it will not be hum free, unless you have the other coil somewhere.
The title was Tri-coil, but in his post, I only count 2.
T

[Stilts]

I guess Stilts will have to clarify what he means, but to me it looks like he wants a humbucker with a normal coil on the neck side, and a coil split in two on the bridge side, kind of like the usual split coil used on the basses to cancel hum, but maybe avoiding the offset. The question is how to wire and switch it so that it cancels hum when used "sc" or "hb" and gets the signal right in all modes.

Bingo. I should probably have explained a little more clearly, here's a picture of what I was thinking:


Could I perhaps avoid the phase switching if I were to just make the neck side a split coil as well?

[dwmorrin]

If you've got two split coils, now we've got to re-title the thread "quad-coil" humbucker.
Two humbuckers should remain humbucking which ever way you wire your switch. So, yes that's a simpler approach than the "tri-coil."
So could we think of the original idea as making a P and a J pickup under one cover?
What I was trying to get at before was to define the "single coil" sound.
To me, a single coil setting means exactly that- one coil.
A split style pickup is a different animal, in my opinion.
So to get series/split/parallel sounds, the classic, dual coil makes the most sense

[Stilts]

Well, I'm unfussed as to the "single-coil" sound - my favourite jazz bass bridge pickups have been the split coil designs. I might just have a crack at the four split halves instead of the one and two, just to make things a little easier. Thanks for the thoughts everyone

[Mike Sulzer]

I think that would do it. Both split coil pairs would be humbucking. Using them together to get a humbucker sound would just be a matter of switching them in series. You might have to settle for lower than normal output in order to fit the coils in as you have drawn them. You could consider dual offset pairs.

Bingo. I should probably have explained a little more clearly, here's a picture of what I was thinking:
[ATTACH=CONFIG]26507[/ATTACH]

Could I perhaps avoid the phase switching if I were to just make the neck side a split coil as well?

[David Schwab]

Use 4 coils, i.e., two split coils. Barolini does that.

That way you don't have phase problems from having half of the split coil's magnets reversed.

You can switch between all four coils for a humbucker sound, and a few combinations of split coils.

[Jim Shine]

Hello,
Isn't there a humbucker already (or in days gone by) on the market with 3 coils ?

Yes. The Mighty Mite Motherbucker. I have one here, though I never really examined it. Some will point out Hamer as well, but I had one and it was really two pickups. A humbucker and a single coil wound on a humbucker bobbin placed beside. Ibanez did one as well, but I am not sure if it was a true one piece part like the Motherbucker or separate pickups like the Hamer.

[spichael]

Hey how are you guys! it seems like mounting three coils that would all be magnitised would require a fourth coil witch is no big deal but I'd suggest looking at the mm 4.3 its a standard music man with an unmagged coil mounted below it. The unmagged coil will be grounded with you standard ground line for a mm witch should keep the amount of connections needed to a minimum for SRS/PAR wiring