by Jarno » 13 Aug 2012, 11:01
Interesting experiment, I think Rick Turner also mentioned that you can get rid of quite a bit of hum by using a dummy coil, which doesn't need to be exactly the same shape or number of windings as the pickups (or thickness of wire used). He was talking about the humcancelling system that Alembic uses (which he helped to design). In an Alembic there's the middle "pickup" which is actually a dummy coil, Rick's idea was to just put a coil in the control compartment.
These are active systems however, and I think that would make it a lot easier to tune the coil to deliver exactly the right amount of anti-hum signal, but maybe that'll change your sound too much (although it is perhaps preferrable to find a way around this, and have a guitar which is bomb-proof in EMI-rich environments, than have something which is passive but doesn't work all the time).
Edit:
If you are using an active system, adding a mixer stage for the center pickup is easy too. One two-input mixing stage per pickup (pickup + dummy coil), so that's three opamp stages, perhaps use one opamp for a precision voltage reference, you'll get by with using a single quad opamp package, not too bad.
"It crackles....., but that's ok"