Some humbucker questions...

[cdub66]

Hi all!
I'm wondering...

-do all 12 pole pieces pick up vibrations and turn them into sound or just 6?

-I like the look of pickup covers and am toying with the idea of adding some to my SZ520QM, how do the covers not interfere with the magnetic field? Would the covers with the holes for the pole pieces to poke through be better in this regard, or is it always a trade-off and uncovered is better tone wise?

Thanks in advance! :food-smiley-004:

[dwagar]

I'm not sure what pickup you are referring to, but the height of the pole pieces do affect the tone.

Covers add, I've read, a bit of capacitance. ie, the pickups will be a tad brighter without the covers.

[Wheeman]

Pickup covers are made of a non-ferrous material, like Aluminum, so it doesn't affect the magnets. Covers will affect your tone a bit as well, especially if you pot the coils in wax. This helps eliminate some of the microphonic characteristics of some pickups.

All 12 poles do pick up vibrations. If I recall correctly, there are six poles in one direction with the other six in the other to "humbuck".

[zontar]

It's simple to try your pickups with & without covers--as long as you haven't sealed them. I've tried most of my electrics with & without covers--and have each of them the way I prefer them. I have covers on my Iceman (which has cool looking covers (the Flying finger), but they're sealed in, so it would too much trouble to remove them.) I don't have covers on my Les Paul or my Les Paul copy--they sound better that way.

[greco]

The height of the pickup (distance between the pickup and strings) and the heights of the individual adjustable pole pieces also have an influence.

The Seymour Duncan website has a lot of information on this topic (i.e., covers, heights, etc). It has also been discussed frequently in their forum. Worth reading.

Peace

Dave

[mhammer]

My sense is that the earliest explorations of uncovered HB pickups were really intended to simply be able to move the pickup closer to the strings and produce more output that way. Since the cover adds some height to the overall assembly, you can bring the whole coil and polepiece a little closer to the strings without interfering with "pickability" if you take the cover off. What people may have learned about the electro-magnetic changes in the response and properties of the pickup since that time is a whole other thing. I doubt that anyone prior to the 1990s or late 1980's removed the covers for the purposes of altering capacitance, etc.

Assuming all polepieces are coupled magnetically, all 12 (or 22 in the case of Carvins or both blades in the case of dual rails, etc etc) are contributing to the detection of string movement. ANY conventional magnetic pickup really senses the area between the north and south poles of the magnetic field. In the case of SC pickups, one of those poles is far enough away that the pickup tends to sense what is closest to one pole more. In the case of HB pickups, the shape of the entire magnetic structure (including any polepieces that are magnetically coupled to it) is such that the string sits directly above both polepieces allowing llower order harmonics to have more of an influence over that magnetic field than would be the case with a SC pickup. Of course, were it possible to have a guitar with a mounting braket that let you rotate a "normal" HB 90 degree so that one set of polepieces was much closer to the strings than the other set, it would likely start to sound much more like a SC pickup, or rather a stacled humbucker.