Pickup winding question

[Steve Dallman]

I am building a 5 string, 51 Precision bass and want to wind a 5 pole, side by side, humbucking pickup. One coil will have two poles and the other 3 poles.

Do I wind the three pole coil the same as the two pole, or should the 3 pole side have 3/5th's winding compared to 2/5ths on the opposing, two pole side?

Thanks in advance.

I would also consider winding a stacked humbucker but need a little info on winding those coils.

So far the only pickup winding I've done is for repairing bad coils in pickups.

[David Schwab]

I haven't done this myself (yet) but I would imagine you want to wind both coils the same turn count ... it is a humbucker after all. I have seen some 5 string P bass pickups where they had a 6th pole in one coil... just for balance. I think it was just a slug.

I'm currently working on a stacked Jazz bass pickup. It's wound, but I haven't had a chance to try it out yet. I think the side by side humbuckers, like a P bass, sound better.

There's a few ways to do a stacked pickup. The difference is in the magnet arrangement. Some have opposite magnet polarity in each coil (magnets in between the coils). Some have the magnets running all the way through both coils, and some have a dummy coil on the bottom with no magnet... with/or without a metal load.

[SK66]

You are in a pinch..Besides having a "quick return" in the fields, you also have the epitome of unmatched coils. If you wind them the same you will get unequal volume but more hum cancelling, if you wind 3/5-2/5 you will get more even volume balance but less hum cancelling...My best guess is to go more towards the 3/5-2/5 and accept a little noise...also, a lower overall wind count will help minimize the issue.

[David Schwab]

This isn't a big deal. Both EMG and Bartolini make 5 string split pickups where each coil is a different size. I guarantee they wind them to the same DC resistance for hum cancelation, since they are quiet pickups.

Here's an example:

http://www.delano-pickups.com/englis...g/pmvc5fe.html

[David Schwab]

Here's another one... this time a Jazz pickup:

[Mark Hammer]

Don't invest too much into the notion of matched resistance.

Hum-rejection is a property of matched turns and "antenna properties". The coil DC resistance is a pretty useful indicator of matched properties when the two coils are wound on identical-sized/shaped bobbins with identical wire and winding tension and the same number of turns. Once the two coils become dissimilar in one or more of those parameters, however, DCR becomes a less useful basis for matching in order to cancel hum.

I'm not saying that a 3/2 split in a pickup for a 5-string bass would NOT be capable of hum-rejection. Rather, given the dissimilar bobbin size, I think you'll get a more usable outcome if the coils are matched for #turns rather than DCR.

[David Schwab]

That makes sense. I wind by turn count myself, and only take DC resistance reads for my own info.

Aero makes a 5 string J bass pickup with 6 magnets.

They say this on their website:

Odd string pickups have an even number of magnets (e.g. 5 string pickups have 6 magnets, the 6th unmagnetized magnet is on the high string side)

There are many paths to the same outcome!

[Dave Kerr]

How about using 43 gauge for x# of winds around the 3 (or 6 for JB) poles, and 42 gauge for the same # of turns around the other 2 (or 4) poles? Output should balance pretty well, and the thicker wire may compensate a bit for the reduced footprint of the smaller bobbin. Maybe using a heavier build insulation on the smaller bobbin would help, too.

[Pep]

+1 for same number of turns vs. DCR (for noise cancelling properties). Personally I would use the same guage wire. You can always compensate for volume differences with pickup height.

[Joe Gwinn]

Don't invest too much into the notion of matched resistance.

Hum-rejection is a property of matched turns and "antenna properties". The coil DC resistance is a pretty useful indicator of matched properties when the two coils are wound on identical-sized/shaped bobbins with identical wire and winding tension and the same number of turns. Once the two coils become dissimilar in one or more of those parameters, however, DCR becomes a less useful basis for matching in order to cancel hum.

I'm not saying that a 3/2 split in a pickup for a 5-string bass would NOT be capable of hum-rejection. Rather, given the dissimilar bobbin size, I think you'll get a more usable outcome if the coils are matched for #turns rather than DCR.

I agree that turns count (not DC resistance) is the key.

Actually, for best hum rejection one should match by area-turns product, so the 3-pole section would get fewer turns than the 2-pole section. Assuming that the area of a "pole" (including surrounding air) is constant, the turns counts for a 3:2 split would be in the ratio 2:3 (yes, reversed, as 2:3x3:2=6:6), so the 2-pole section has 50% more turns than the 3-pole section. The wire guage is irrelevant, and need not be the same. Likewise, DC resistance.

One consequence of this is that the 2-pole section will be very slightly louder than the 3-pole section, at least in theory. Probably one can if needed simply adjust string-pole distances to compensate, as another poster suggested.

[jworrellbass]

I just googled "5 string split coil bass pickups"(jazz bass pups) and I found this thread. It almost seems that their isn't a definite answer for the best hum cancel design. Does anyone have a proven method?
I have to wind a set this week, so should I wind the 3 and the 2 magnet coils the same number of turns, say 6000 turns each. Or should I wind the 2 magnet coil 50% more turns? 6000 turns 3 coil/ 9000 turns 2 coil?
The other question I have is should the 3 mag coil be on the bass or treble side.
Thanks in advance.
John

[bsmith]

can you do a tele type bridge pickup stacked with the magnetic pole piece running through both coils and have it still hum canceling?

[Dave Kerr]

I just googled "5 string split coil bass pickups"(jazz bass pups) and I found this thread. It almost seems that their isn't a definite answer for the best hum cancel design. Does anyone have a proven method?
I have to wind a set this week, so should I wind the 3 and the 2 magnet coils the same number of turns, say 6000 turns each. Or should I wind the 2 magnet coil 50% more turns? 6000 turns 3 coil/ 9000 turns 2 coil?
The other question I have is should the 3 mag coil be on the bass or treble side.
Thanks in advance.
John

I'd say you'd be best off compromising, balancing imperfect hum cancellation against imperfect signal strength balance, and experiment with pole height as mentioned just upthread. Figure out the average area of each wind on each bobbin (ballpark) as suggested - I suspect you'll find that the two pole average turn area would be more like 60% of the 3 pole bobbin, but that would all depend on the pole piece diameter, string spacing and whether/how thick you tape the pole pieces. You can then tweak the turns count a bit, upping the 2 pole count a bit to better balance hum. You could also tape the core of the 2 pole bobbin with enough extra wraps of tape to boost the average area of each turn, and at the same time reducing the strength of the signal generated by reducing the exposure of the coil to the magnetic field.

Edit - I just read the entire thread, and 90% of what I just wrote was better stated by others up thread, but I think wrapping the 2 pole bobbin with some extra tape might be worth trying.

[David Schwab]

can you do a tele type bridge pickup stacked with the magnetic pole piece running through both coils and have it still hum canceling?

Yes. That's how most stacked pickups are made.

Keep in mind that the magnets have the poles on the ends, and are null in the middle.

[David Schwab]

I have to wind a set this week, so should I wind the 3 and the 2 magnet coils the same number of turns, say 6000 turns each. Or should I wind the 2 magnet coil 50% more turns? 6000 turns 3 coil/ 9000 turns 2 coil?
The other question I have is should the 3 mag coil be on the bass or treble side.
Thanks in advance.
John

I'd start off winding the same number of turns on each coil. That's what's important, not the DC resistance.

I'd put the bigger coil on the treble side, but it probably doesn't matter.

Here's a Nordstrand. You can see that the smaller coil is slightly fatter, so they are probably using the same number of turns on each coil.