Grounding issue ?

Discussion in 'PTC - PRS Tech Center' started by BGood, Oct 2, 2018.

  1. BGood

    BGood New Member

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    Soapbar SE. I have hum when not touching strings/bridge. Don't tell me it's a P90 thing, I have several P90 guitars. This is not it.

    I checked with a meter and there is continuity between bridge and any of the electronics.

    What am I missing ?
     
  2. bodia

    bodia Authorities said.....best leave it.....unsolved

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    Sounds like a P90 thing, to me. I have had P90s that hum, unless I have both pickups selected.
     
  3. BGood

    BGood New Member

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    Right ... o_O
     
  4. DickBanks

    DickBanks New Member

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    Really though, you should always hear a 60 Hz hum with a single coil pickup selected. An excellent indication that a wire is loose on a single coil is if the hum goes away completely.
     
  5. garrett

    garrett Not a New Member

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    That's actually the opposite of a grounding issue. It means the grounding is working as designed.

    Guitar electronics are antennas for RF noise (not to be confused with 60 cycle hum). The string path is grounded, so when you touch the strings, the noise goes to ground. You can reduce this noise by shielding the electronics cavity.
     
  6. BGood

    BGood New Member

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    I know about P90 hum, I've had P90 for years, I embrace it, it's part of the tone.

    So, why is it when I play (just did to check again) my cheapo $84 Epiphone LP Special with P90, it keeps the same normal P90 hum when I let go of the hardware. The SE in the same amp, same cable, same angle/distance to the amp, same lights on, same cat roaming around (and a bird just hit the sliding glass window ... boing ... really !) ... so, the SE in the exact same situation, buzzes like a swarm of buzzers.

    Ground between bridge and electronics checks with a multi meter.
     
  7. garrett

    garrett Not a New Member

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    The SE makes a better antenna.

    Or the Epi doesn't ground the bridge, so you're getting 60 cycle plus RF noise the whole time?
     
  8. bodia

    bodia Authorities said.....best leave it.....unsolved

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    Ok, so seriously, does it happen anywhere else? Meaning, have you tired it at a buddies place with the same result? I ask, because I've been to a buddies house, and he has this problem with P90 guitars and high end strat types. He went so far as to hire an electrician for a day to trouble shoot it. Turns out it's the automated meter device that the water company installed. It's obnoxious in one room, and not so bad in others.
     
  9. BGood

    BGood New Member

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    Again ... it's the only single coil guitar amongst the five I have that does it.
    It did it at the summer place too, a month ago, but I don't remember it being a problem before, because it would have bugged me.
     
  10. garrett

    garrett Not a New Member

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    Single coil or humbucker doesn't matter when it comes to interference buzz. My Custom, 594, and a strat with noiseless pickups all buzz in my house. Touch the string path and, zap, it's gone.

    My quietest guitar is actually my only one with true single coils in it. That's because it has an Ilitch noise canceling coil and the routs are fully copper shielded.
     

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