The Electra Forums

Anyone with first hand experience in potting pickups, specifically how it changes the sound?

A local guitar shop says that the temperature required for potting is also the precise temp required to "turn the windings into spaghetti" for old pups like our MMK's and Super Distortions.

Love to hear from anyone with first hand experience in this, with details on how it changes the sound.

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"GREAT Googiley moogilie Jack...jumpin jehosephat, hot dang and all".
- jdwhealton

Unless you play with super high distortion I wouldn't bother. Usually they have more open tone without the potting.

It's not really high gain, just hard rock, but standing in front of the amp on a smaller stage will squeal. Some of squeal, not all. The Electra's all squeal.

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"GREAT Googiley moogilie Jack...jumpin jehosephat, hot dang and all".
- jdwhealton

Your local guitar shop tech is an idiot. Properly done potting will not damage the pup. Sorry to put it so strongly but when you come in with the question you deserve an honest answer, or at least an "I don't know". The wax used for potting melts at under 150F Copper melts at over 1,900F. The insulation used on the coils will start to soften at around 300F.

I know some people say that potting a pup will change the tonal characteristics but as a scientist I don't understand how. The coils set up a magnetic field. The field is dependent on the gauge of the wire used, the number coils, the shape of the coil, and current running through the coil. The kind, geometry, and strength of the magnets used also has an affect. I don't understand how wax potting would change any of that. I have potted MMK pups and been glad to do so. If you check over on the Matt page, you will find that it is standard advice for people who use their MMK equipped guitars live to pot the pups.

Love it, thanks for the input. About the spaghetti thing, I don't know what he was talking about, I'll ask him when I see him next.

Insulation is all I could think about, but if that carries a 300 degree melting point then no need to worry. What material is it insulated with on our old pups?

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"GREAT Googiley moogilie Jack...jumpin jehosephat, hot dang and all".
- jdwhealton

The wire used on most older pups used lacquer as an insulation. It doesn't melt at 300F but will soften, possibly allowing for the coil to deform. You also have to take into account if the bobbins are plastic as they can soften. So temperature control is important.

What is more important is that the wax used is flammable. Don't use an open flame to melt the wax and keep it at a temperature that will just keep the wax melted. It little care and you will do just fine.

I know a little bit about it - I contributed an article for the "guitar nuts" site in the 90s. I have potted MANY MANY electra (and other US and import) pickups. I usually DON'T pot them unless feedback is a problem. I have learned over the years that the unpotted pickup has a bit more perceived treble - maybe even a harmonic quality too them. The tendency to feedback makes the pickup a bit livelier sounding I suppose is what I am trying to say - it is subtle but is there. I don't have a scientific explanation for it, but the ears don't lie. It is part of what we like about a vintage PAF sound as the most accurate sounding models (and the originals) are unpotted. It wasn't usually needed back then, and many pickups don't start feeding back until they have some age on them. The early and best sounding dimarzio super distortions were not potted as well. There is something to it.

But there are a lot of excellent sounding potted pickups, and if you crank the distortion it is almost a requirement. I wind put potting many of my MMK45s. If your pickup is particularly microphonic you can't use it in these situations, so potting is preferred. You really can't go backwards, so remember this. The risk is usually very minimal with MMKs, and I have done the maxons too (earlier MPC types) and I have not ruined one. I think most of the risk is taken away by watching the temperature, and the more risk probably lies with the handling of the pickup, some of the maxons can come apart if the cover is removed, and the plastic pieces warping or melting - not an issue with my experience with MMKs or Maxons used in Electras. I'd say don't take the cover off. I have not potted EVERY STYLE of electra pickup from every manufacture, but I have potted MANY of the most common type. The trick is get your temp right at the wax melting point, and don't let it get overly hot. Be careful, wax is very flammable so you have a built in fire hazard so use some sense when doing it. Melted directly on a gas flame or even an electric burner is a recipe for calling the fire department - similar to a grease fire. If you have ever experienced one of those, they are bad news. But I potted my first pickup I think in the very early 80s in high school after reading an article in guitar player magazine.

There have been a few rare situations where potting seemed to take a LOT of the high end off, one being a mini humbucker I had a long time ago. This is very rare, but it happened. It was a cheap pickup and not a good or valuable one so it didn't really matter too much - not an MPC. But this stuff can happen.

And what I do is more coil immersion rather than potting, as I keep the pickup in there until it reached the temp of the wax, and the wax works its way into the coils. If you just dip them in and out - you get a nice coating of wax around the outside (some refer to this as "lightly potted") and that may not stop the real microphonic issues. If you have a VERY VALUABLE VINTAGE guitar, don't do it without talking to someone that appraises vintage guitars - they will likely advise against it. That being said, it works GREAT on electra humbuckers and I have likely done more of than anyone (since I have been potting electras, epiphones, and imports since the 80s).

Just think safety and use extreme caution. Use a double boiler. It is just like melting candle wax because it is a mixture of candle and beeswax. No, don't melt your wife's yankee candle (I suppose your pickups will smell better that way, but I don't think that is what you are going for). Get it just hot enough to melt the wax completely and do its job. I am sure you can melt one if you crank up the heat and ignore it. But you can burn up your car engine if you ignore temperature too, so the moral is don't ignore the temperature!

Here is a detailed link on the pickup potting procedure I use:
http://www.guitarnuts.com/technical/electrical/index.php

I am going to save or "sticky" this article because we repeatedly get questions about potting and this covers it well.

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Thorny