Physics anyone? why cover a pickup?

Discussion in 'Pickups & Electronics [BG]' started by Whil57, Sep 30, 2017.


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  1. Whil57

    Whil57

    Aug 7, 2013
    Long Island
    Just wondering, as i like to see my little magnetic poles, is aside from aesthetics, why cover a pickup? Isnt that like a tone killer?
     
  2. Pole pieces are covered for aesthetics. There are no tonal differences between covered and uncovered pole pieces. Don't overthink it. There isn't much to this.
     
  3. Jazz Ad

    Jazz Ad Mi la ré sol Supporting Member

    As long as the cover is amagnetic, it doesn't change tone.
    They can hidden for protection against friction, aesthetics and also commercial reasons. A lot of people wouldn't buy EMG or Bartolini pickups if the blades shown.
    If the cover reacts to magnetism (metal) it can affect tone or be used as a protection against noise.
     
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  4. Axstar

    Axstar

    Jul 8, 2016
    Scotland
    I quote like covered pickups. I'm reworking my Jazz bass in the next few weeks/months, and I'm tempted to put solid pickup covers on it. The only problem is that it can make instruments look more 'metal' as the EMG association is there.

    The pickup doesn't 'see' the cover, so there is no problem there. Plus, there is no chance of your strings hitting the poles when they are covered.
     
  5. I have not seen very many metal pickup covers without pole pieces. I know that there are some Thunderbird pickups like that, but most of them have holes for the pole pieces.

    Indeed, a metal cover will change the tone, due to inducing the flow of Eddy currents. That has to do with the material the cover is made from, rather than the fact that it hides the pole pieces, though.
     
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  6. Whil57

    Whil57

    Aug 7, 2013
    Long Island
    Overthink, yeah, i cant help it. I figured it like this. People argue unfinished wood, versus lacquer, versus vinyl as finishes, and that is only reflections, so it would seem to me, putting any physical barrier between contact would have to something.
     
  7. BassUrges

    BassUrges

    Mar 14, 2016
    Denver
    I wish my jazz had covered pole pieces. I've been hitting them with the strings lately.
     
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  8. two fingers

    two fingers Opinionated blowhard. But not mad about it. Gold Supporting Member

    Feb 7, 2005
    Eastern NC USA
    There is not "contact" of any kind. The magnets create a magnetic field. The pole pieces don't even have to line up with the strings. They create one field. There are not separate magnetic fields shooting straight out from each pickup pole piece.

    The magnetic fields goes right through plastic. It is not affected in any way. The affect on tone of plastic covered pole pieces is exactly and precisely zero. None. No affect at all.

    Zero.
     
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  9. micguy

    micguy

    May 17, 2011
    Covers (and epoxy potting) are good for environmental protection. Your sweat is about the worst thing for pickups, keeping the sweat and the metal parts in your pickups separated is a really good thing.
     
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  10. BlueMINI

    BlueMINI Supporting Member

    Sep 10, 2013
    Olympia, WA
    If you ever disassemble a pickup, you will find that the thin copper wire wrapped around the pole pieces is VERY fragile. Those covers offer a bit of protection. Check out early Telecaster pickups-- those had string (twine of some sort) wrapped around the pickup to protect it.

    Any discussion of tone will always be relative... you could think of the covers as an essential part of the instrument's tonal characteristic-- along with the color of the pickguard of course ;)
     
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  11. Maybe we can think of this type of pickup cover as similar to the "acoustically transparent" grill cloth.
     
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  12. bolophonic

    bolophonic

    Dec 10, 2009
    Durham, NC
    Dirt.
     
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  13. socialleper

    socialleper Bringer of doom and top shelf beer Supporting Member

    May 31, 2009
    Canyon Country, CA
    It is all magnetics not microphonics. Strong enough magnetic waves will pass through 1mm of plastic.
    I don't like pole pieces that stick out because they make a terrible noise when you play hard and the string hits them. I also don't like large exposed pole pieces for the same reason.
     
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  14. rodak

    rodak

    Jun 14, 2005
    I can see that plastic covers wouldn't affect the sound, but wouldn't metal covers have an affect?

    Back in the '70s, I played in a band with a guitarist who had a stock Les Paul. We convinced him that if he'd remove the pickup covers, it would improve his sound. So he showed up at the next practice with, not the covers, but the pickup mounting rings removed, and the still-covered pickups were knocking around loose in their cavities and banging against the strings. Sheesh, what a maroon!
     
  15. Ric5

    Ric5 Supporting Member Commercial User

    Jan 29, 2008
    Colorado
    I convert 4 string Rickenbackers to 5 string basses.
    A metal cover will help shield the coils

    A plastic cover will protect the coils from physical harm

    And some covers will cover pole pieces and that keeps you from getting that pop sound when strings hit the pole pieces
     
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  16. Drgonzonm

    Drgonzonm

    Sep 4, 2017
    American SW
    Look at the old lipstick pickups. My guess the metal was a 300 not a 400 series stainless steel.
    Correct error of series
     
    Last edited: Oct 1, 2017
  17. Whil57

    Whil57

    Aug 7, 2013
    Long Island
    This was good to know, now i can adjust the bridge without worrying the string is off center to the poles.
     
  18. James Collins

    James Collins

    Mar 25, 2017
    Augusta, GA
    Agreed.
     
  19. megafiddle

    megafiddle

    May 25, 2011

    My guess would be nickel or chrome plated brass.

    -
     
  20. john m

    john m Supporting Member

    Jan 15, 2006
    Some metals are acceptable.

    Thin aluminum covers are ok--- it's the iron ( steel) that's not good-unless you are making a magnetic device.
     
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