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a different twist on buzzing jazz pups

Discussion in 'Pickups & Electronics [BG]' started by Matthew T., Nov 27, 2004.


  1. Matthew T.

    Matthew T.

    Feb 17, 2002
    Springdale, AR
    I'm back after a year with a little more info on my buzzing Ultra Jazz pups. They act like they aren't grounded, with a buzz whenever I touch the exposed pole pieces, and not the strings. Here's the twist, this only happens when I touch the pole pieces on the bass side. The pickup cavities and the control cavity are coated with conductive paint. The back of the pick guard is, too. I've checked the wiring against the instructions over and over. The Ultra Jazz pups have two small pups end to end in each cover. Apparently, the bass-side pup in each cover isn't grounded. He'p.
     
  2. luknfur

    luknfur

    Jan 14, 2004
    DIXIE
    FWIW:

    hopefully somebody will jump in that knows more but if not, I'd try swapping the leads on one of the pups and see what happens - which may throw it out of phase - but just to check the grounding. Cause it definetly sounds like improper grounding of some sort. Then I'd try swapping the leads on the other and check the response. It's not unheard of for pups to be improperly wound/wired. Also seems some manufacturers wiring diagrams can be generic and not necessarily geared to a specific set of pups.
     
  3. luknfur

    luknfur

    Jan 14, 2004
    DIXIE
    FWIW:

    hopefully somebody will jump in that knows more but if not, I'd try swapping the leads on one of the pups and see what happens - which may throw it out of phase - but just to check the grounding. Cause it definetly sounds like improper grounding of some sort. Haven't had those pups but it sounds like they may be 4 wire w/ground so you should need to swap the bass side wires in that case. Then I'd try swapping the leads on the other and check the response. It's not unheard of for pups to be improperly wound/wired. Also seems some manufacturers wiring diagrams can be generic and not necessarily geared to a specific set of pups.

    David's had these pups so he'll probably respond in confirmation or with the appropriate fix.
     
  4. David Wilson

    David Wilson Administrator Staff Member Administrator Supporting Member

    Oct 14, 2002
    Lower Westchester, NY
    I'm assuming you've wired them stock, e.g. red to vol pot, green grounded and black and white together.

    How is the black/white combo shielded? Tape or tubing?
    How are you doing your grounding? Are you doing it via cavity grounding , shielding tape/pickguard , back of vol pot or what?
     
  5. Matthew T.

    Matthew T.

    Feb 17, 2002
    Springdale, AR
    I have them wired standard. There's electrical tape around the soldered ends of the black and white leads. The grounds are attached to the back of the volume pots which are grounded to the bridge. All internal surfaces except the pots and jack are coated in conductive paint.
     
  6. luknfur

    luknfur

    Jan 14, 2004
    DIXIE
    The electrical tape is a bit bourgeoisie and should be shrinkwrap but as long as the connection is sound not an issue as long as the tape stays in place. A wirenut would probably be better (small wirenuts and shrinkwrap can both be had at Home Depot) cuase I've never had any luck with electrical tape staying in place even for temporary applications. Doesn't sound like this problem but it will cause racket if the tape comes off in the future and partially shorts somewhere.

    You can take a meter and run it pot to pot, pot to jack, and jack (where you plug in) to bridge to check ground connections. That might tell you something. I'm guessing you'd get different readings if you ran the meter from the bass pup poles to a pot and the treble poles same.
     
  7. Matthew T.

    Matthew T.

    Feb 17, 2002
    Springdale, AR
    I posed my problem to DiMarzio and just received Steve Blucher's reply:

    The magnets aren’t grounded, and the E & A coil is the ‘hot’ one, hence the buzz. There isn’t anything you can do, but as you have noticed, there is no buzz when either hand is also in contact with the strings. Since that should be the situation most of the time, we hope the buzz won’t be a serious annoyance.

    So I supposed I'm stuck with the buzz.
     
  8. luknfur

    luknfur

    Jan 14, 2004
    DIXIE
    FWIW:

    that's interesting. Often the poles are grounded. I don't recall anybody else with a similar complaint about these pups. I don't even recall BP mentioning anything about hum in their shootout.
     
  9. Matthew T.

    Matthew T.

    Feb 17, 2002
    Springdale, AR
    Momma always told me I was special.