=========================================================================== Stewart-MacDonalds 4-Conductor Humbucking Pickup Wiring Combinations: =========================================================================== I got this from a Stewart-MacDonald's catalog. Mike Lindskold, Technical Advisor, wrote it in late 93/early 94 (don't have date handy). It is a handy guide/faq. Tim Stanley --------------------------------------------------------------------------- Consider the two coils of a humbucker pickup: Coil 1: A _OOOOOO_ B having terminals A and B Coil 2: C _OOOOOO_ D having terminals C and D Pickup Manufacturers Color Codes: A B C D --------------------------------------------------------------------------- Anderson red green black white DiMarzio red black green white Gibson black green red white Jackson green white black red Lawrence black green red white Schaller green white yellow brown Seymour Duncan black white green red (the bare/shield wire is always soldered to ground) Wiring Options: Series linked / out of phase:* A-hot B&D-series link C-ground Series linked / in phase:** A-hot B&C-series link D-ground Parallel linked / out of phase: A&D-hot B&C-ground Parallel linked / in phase:** A&C-hot B&D-ground * Standard humbucker wiring arrangement ** Non-humbucking --------------------------------------------------------------------------- Here is some additional related info from: scott andrews sha3u@virginia.edu --------------------------------------------------------------------------- i have read these columns in the Stew Mac catalog. i think they are very informative. one problem - from the instruciton sheet Stew Mac sent me with my Lawrence XL-500 and from the sound of the XL-500 when wired up, the red and black on mike lindskold's chart for Lawrence are backwards. red is A, black is C. A pickup's phase is always in comparison to something else - another coil or another pickup. the wiring diagram included with my XL-500 pickup and written by the Stew Mac people had 2 of the colors reversed from the little chart in the catalog. one of the two had to be wrong - they couldn't both be right. humbucker wiring instructions usually assume that a bridge humbucker has the coil nearest the neck connected to ground on one end and the coil nearest the bridge connected to the hot output. (the other ends of each coil are connected together.) if you follow this, and all the manufacturers i have dealt with and all the other color codes listed in Stew Mac's little chart do follow this as near as i can tell, then the Lawrence color codes on my pickup wiring sheet are correct and the ones on the little chart are wrong. it must just be a typo. i realize that reversing thse two wires will only change the phase of the pickup, but both wire color charts can't be correct. i'm not positive on all this, but i think neck pickups are the opposite - the coil closest to the neck is wired hot and the coil closest to the bridge has one end connected to ground. i think the old gibson PAF humbuckers had the adjustable screw pole pieces only on the "hot" coils - adjusting on the "hum-cancelling" coil won't make as much difference. [duncan JB humbucker has this - only 1 set of 6 adjustable pole pieces rather than 12.] that's why the screws on the PAFs on a 2 humbucker guitar, like a les paul or an SG, are on different sides of each pickup - bridge humb pole pieces closest to bridge, neck humb ploes closest to neck. if you change the phase, though, you throw all that out the window. if you run a duncan JB out of phase with what the manufacturer suggested, your "hot" coil is the one without adjustable pole pieces. this gets wierd when you want to wire 2 humbuckers to split and combine coils. the guitarist in Dream Theater had a 3 position switch that gives him bridge, both middle coils [hum- cancelling], and neck. to do this, the two pickups have to be arranged the same way, with both "hot" coils pointing in the same direction to make the middle two coils have opposite polarities. i can't figure out how they wired this with a 3 pickup SG type switch like STew Mac sells. they may have used a different switch. i don't know how much difference the "directionality" of the humbucker makes in the sound. obviously it is very important in phasing with another pickup, but i don't know if it matters using one humbucker alone. i haven't ever tried to find out if running the coil closest to the neck as "hot" gives a more neck pickup type sound than running the bridge coil "hot." the distance between the coils is much smaller than the distance between a neck and bridge pickup where you do hear a difference in sound. i keep using those damn quote marks on "hot" because both coils are actually hot; both coils are connected to the output. i think "directionality" might be the best word to describe this. scott andrews sha3u@virginia.edu --------------------------------------------------------------------------- Comment from Tim: No doubt Scott found a problem here when using his pickup with some other pickup(s). Like he says, always remember, pickup coil phase is always "with respect to" another pickup or coil. This can get confusing. A bit of trial and error is sometimes necessary when using pickups from varied manufacturers. Start by just reversing hot and ground. Finally, I keep a faq that describes one simple method to sort these things out using just a simple *analog* volt meter.