Double P-Bass Pickup wiring - Double Reverse?

Discussion in 'Pickups & Electronics [BG]' started by Remus_Redbone, Feb 19, 2014.

  1. Remus_Redbone


    Dec 27, 2010
    Western AR
    I've done a significant number of searches here and on the web in general to find an answer to this question with no luck so far, so here goes....

    I have put two P-Bass pickups in an experimental parts bass. The pickup in the original position is a Seymour Duncan Antiquity II / 60's, and the bridge position pickup is a stock MIM P-Bass pickup from around 2008.

    When I wired these up, I went with two volume controls and no tone control at all (stack knob setup coming later). Both p/u's have the two coils in series just as they were originally made.

    Here's the issue and the question; When I wired these up, I observed polarity on each the same, white is signal and black is ground. When I first tested the bass, each p/u sounded good solo, but it was extremely thin with both on. It sounded exactly like you would expect with two out of phase pickups. I reversed the polarity of the MIM stock p/u in the bridge and now both sound good solo and both sound good together.

    Q: Is this normal due to the reverse wiring of ONE of the P-bass p/u's coils OR do I have two P-pups that happen to be reverse polarity from each other?

    Is it likely that each p/up has reverse winding as normal, but a different coil is reverse wound in each pup?

    It's a problem that is solved, but I'm trying to figure out what I have here for future reference....:meh:
  2. ctmullins

    ctmullins fueled by beer and coconut Supporting Member

    Apr 18, 2008
    MS Gulf Coast
    I'm highly opinionated and extremely self-assured
    Sounds like a simple matter of two different manufacturers using different wire colors. Or, to think about it from the other direction, two different manufacturers using different standards for polarity/winding direction.

    I had this exact problem once when I paired a Duncan SPB-2 with a standard Fender J pickup. Safe to say that Duncan's black = Fender's white, and vice versa.
  3. Bassamatic

    Bassamatic keepin' the beat since the 60's Supporting Member

    Yes - it sure seems that their outputs are are of phase. I have also been surprised by this once in a while. There seems to be no absolute between manufacturers,

    The way I check is to put my very sensitive analog voltmeter (microvolts) on one pickup, place a metal tool just up to the pickup and pull it away fast, and see what direction the needle moves.

    Of course you can just swap the wires on one pickup to see if it makes a difference. No doubt it will.
  4. Remus_Redbone


    Dec 27, 2010
    Western AR
    I certainly appreciate the feedback and am glad to hear it's not a rare occurrence.

    If P-Bass pups are normally out of phase between the two coils, it's not a problem because they aren't "picking up" the same string. My thinking was the issue is probably which coil each manufacturer winds "right" and which coil they wind "left". If that isn't standard, then two of the opposite wound pups together in the same bass creates an OOP condition. Well, it's fixed now, but I still don't know the actual cause. I guess there are no rules for polarity and any manufacturer may choose their wire colors and winding direction at will as long as they are consistent.
  5. Remus_Redbone


    Dec 27, 2010
    Western AR
    Oh yeah, it sounds fantastic; better than I ever thought it would....