Vacuum Potting Guitar Pickups Explained Video

Discussion in 'Pickups' started by cooljuk, May 20, 2017.

  1. Kaicho8888

    Kaicho8888 Senior Member

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    Excellent video and thanks for explaining the cause/effects of vacuum potting.
     
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  2. cooljuk

    cooljuk Transducer Producer Premium Member MLP Vendor

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    Thanks! It's a subject that is often misunderstood and a practice that is often misused. The more information there is out there, the better the chances of people making the best decisions for themselves, their gear, and their playing situations.
    :thumb:
     
  3. TM1

    TM1 Senior Member

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    Most of the time I find that covers are Not flat on the top like they were made originally in 1957. This crates an air gap between the top of the coils and the inside of the cover which crates squeals. I find a small dab of silicone helps prevent this. However if your coils are not wound correctly or you have other loose parts inside the pickup you'll have microphonic problems.
    Personally, I don't like wax potting a pickup as it alters the airiness of the top end and the pickup just doesn't breath anymore. I heard this shit, believe me.. I know some folks would say I'm full of it, but I do hear a difference between potted and unpotted humbuckings. Now Fender's a different story. Leo started out dipping finished pickups in nitro-lacquer after winding them. He later decided that dipping them in wax took way less time. I don't think that anyone one of us has really heard a non-potted Fender pickup, so our ears perceive them as correct/right. I have a couple of mid-Fifties Strat pickups and they're dipped/potted. Not sure if it's wax or lacquer as I'd have to check the next time I open up my Strat..
    Anyway...
     
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  4. cooljuk

    cooljuk Transducer Producer Premium Member MLP Vendor

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    I know there's a sonic difference in potting all pickups. I hear it all the time. It's certainly measurable with some recording, averaging and graphing but it's so obvious, I don't even see the point in all that work. Anyone who's had a pickup, then potted it, and played it in the same rig should be able to agree unless their rig is all amp/dirt or the pickup was dark and inarticulate to begin with. I really think it's a shame to have to pot a PAF style pickup because it takes away from one of the very qualities that makes these types of pickups fantastic - the open, breathy, airy and detailed top end. Some guys play with such gain and in a way that they actually need it done to gig though and an instrument that can't be played is no good. I think that's a very RARE exception though, and 95% of folks playing vintage style humbuckers don't need potted coils, at all.

    All the 50's and 60's Fender pickups I've repaired have been wax potted (or "compound dipped" - Leo's own words) except maybe a Tele neck. I have 70's Strat pickups that are definitely lacquer potted and I've had another 70's pickup or two here that wasn't potted at all (and would feedback excessively). I guess they missed a few here and there. The bobbins, before being wound with coils, are ALL lacquer dipped until they moved to plastic bobbins, from what I have seen.

    The pickups I've lacquer potted (not under vacuum, that's dangerous with the rig I have - running the fumes through the pump) have had a different sort of result than wax. It created a really nice shell on the outside surfaces to protect the coil and magnets from corrosion and grime but didn't really seep in deep. I suppose I could thin the lacquer down and leave them in longer for better penetration but there's a problem with that - the coil wire insulation is soluble in lacquer thinner or acetone so, at some point, it would destroy the coil be melting away the insulation. I'm guessing, this is why Fender didn't use lacquer for very long. It's also more expensive than wax.
     
  5. AJK1

    AJK1 Senior Member

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    What a riveting video...
     
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