Wax Potting myths..or are they?

welshboyo

OK,

One of the joys of old(ish) guitars is the good ole squealing pickups when you step on the gain pedal...

I can dial out the squeal somewhat by turning down either the gain or volume/tone, however, in the heat of the moment gigs, this isn't ideal so I'm considering potting my pickups...the guitar in question is an early 70's deluxe with mini-hums..

A quick browse of t'internet tells me that potting will introduce a different tone to these pickups and the guitar will lose some of its jangleness - is this true?

Also, I have been told that these mini-hums are delicate little beasts and sometimes get wrecked through potting..again is this true?

What would you guys do, and who would you recommend if wax potting is the way forward?

 

ThePrettyDamned

I don't know - so bear that in mind!

However, I have a non-potted alnico V humbucker from Oil City (a Cowtron).  It is pretty low output (where my duncan custom 5 gives a fair chunky gain, on the same settings, the cowtron is near clean!).  However, even if I pile on gain and volume, I've not noticed a huge amount of squealing nightmare feedback.  So perhaps there is more than just the potting to it?

No doubt it helps reduce it, but tone wise, I've no idea.  I can make mine get squealy by standing nearer the amp when it is cranked up, but I've recorded a metal rhythm track with it and it was okay. Sounded the balls, too.

Drew_TNBD

Feedback is pleasant. Squeal is not.

I've found that every single time I've tried to use a Seymour Duncan JB pickup in a live and loud environment, it squeals like fuck and sounds 'orrible. For that reason I went back to my BKP's, which I believe are potted.

ICBM

I do think that over-heavy potting dulls the 'life' in the pickup - it doesn't change the tone hugely, but it can lose something. It's logical if you think about the vibrations from both the guitar body and the sound in the room getting back into the pickup (or not).

I've never personally seen a pickup damaged by potting but I suppose it's possible if you overheat it. Ask TheGuitarWeasel, he will know!

ESBlonde

There are a couple of things you might try in a non destructive manner. Sometimes it is the cover vibrations that are the fault/cause and sometimes the windings (or indeed both).

There are some potters that only put a small amount in the cover and that stops it without messing with the coil. More temporary I have known that wedging a piece of card/cloth/plastic between the chrome cover and the pick-up mounting ring can attenuate some/most/the worst vibrations that cause squeal and it's fully customisable and reversible.

Everyone has their own myth about potting, mine is that waxing the coils takes away that breathy open clean sound from a nice loose wound low power bucker. If you are using a high gain monster always on 11 it is a no brainer.

OilCityPickups

There are degrees of potting: my hi gain pickups always get a 15 minute soak to fully fill the air gaps in the coils, whereas my Blitz Spirits get a fast minute or  two that only fixes the components and outer few layers of windings. Covered 'Spirits' get drained after potting 'poles down' in a specially designed tray. This keeps the wax between the cover and the bobbin tops, and prevents 'drumming' squeal.
Personally I also use different blends of wax for different purposes. Beeswax is softer and restricts the movement of the pickup's component parts less. Paraffin wax is harder and more brittle, and holds the windings more rigidly. My PAF style pickups get a higher beeswax content bath.
 

welshboyo

thanks guys.

@theguitarweasel, do you offer a potting service for pickups? can I send these to you? and how much!!!

pm me if its easier

OilCityPickups

welshboyo said:

thanks guys.

@theguitarweasel, do you offer a potting service for pickups? can I send these to you? and how much!!!

pm me if its easier

I do offer potting at £10 plus 6.99 P&P, but you do need to be really sure you want them done ... as once done it is for keeps! There is also a small risk with any older pickup that potting will find a weakness.

Misty

I once tried potting the humbuckers on an early 70's 335 I had. The result tonally was that, as ICBM and ESBlonde suggested above, the tone became kind of duller, less breathy and generally less characterful. It did stop the squealing, but it also found a weakness in one of the pickups which actually stopped working. I was lucky that I managed to find, eventually, where the coil was broken and I was able to repair it. I didn't really like the effect the process had on the tone though, and I would never attempt potting again myself, especially if it can be done professionally for a tenner plus postage. If I knew then what I know now I would have left those pickups well alone. 

I later sent the pickups from my '69 Tele to Andy at Wizard Pickups, who potted them for a very reasonable price, and sent them back in a few days. The squeal was gone, and again I would say so had a bit of airiness and character, but on balance the guitar was more usable and I was glad I had it done. This was probably fifteen or twenty years ago, and I still have that guitar.

I would second that you should really be sure you want them done.

welshboyo

@misty, thanks for your advice. I think for now I'm going to leave it be and just be mindful of what this guitar is used for, it's not as if I'm struggling for guitars...I was playing it last night at near on gig level at home, facing the amp and it was fine provided I had the volume or tone turned down, it only squeals on high gain applications and is fine with a crunch type sound..so this is what it'll be used for..

Misty

You're welcome, and that makes a lot of sense to me. Of course you could always change the pickups, but then you're into the realms of undoing original solder joints on a nice old guitar, etc. etc.....complications eh?!

imalone

I tried an experiment a while back where I strung an electric with uncoated nylons, with everything turned right up there was audible sound from the amp. I thought the most likely source was relative motion of coil and magnet in the pickups (a couple of others, like relative motion to other metal parts of the guitar). This was much more noticeable with the stock mid pickup (which I think is unpotted) than the potted bridge pickup. (Can't remember right now what the neck was like, but it's now a blade mini-bucker, so would expect less sensitive to vibration). Wouldn't have expected that cutting that out would make them sound less open, but maybe it's higher frequency stuff. Guessing the wax will also increase the capacitance.

bertie

I wax potted some shrimps once,   tasted fuckin awful

OilCityPickups

All pickups are microphonic to a degree ...

I've done a whole pile of testing, and found this:
about 75% of cases of squealing pickups can be put down to covers. Either having a void over the bobbin tops that allows the top surface to 'drum' or ones not properly soldered on.
A smaller percentage of squealing comes from other loose major components, keeper bars, magnets, slugs etc. The smallest percentage comes from loose windings ... the bit that will influence the sound of the pickup most. My own approach is based on my observation that many mass manufacturers over pot to hell ... probably not wanting returns. They use such techniques as vacuum potting that takes out every minute air space.
Personally I try to reduce tolerances inside the pickup to a minimum so there is less physical room for components to move about that shouldn't. I use a tape material to soak up and hold the wax to the top of the bobbin on all new covered pickups ... thus reducing the amount of wax I need ... then with PAF style pickups I pot for the minimum amount of time for all the major components to be 'fixed' and the outermost layers of the winding wire to be soaked.
I don't offer unpotted as standard ... because I believe that if you do it right you can minimise any 'tone loss' and have a pickup that works well for openness and 'breath'. Of course people can have unpotted if they want ...

sted

I tried potting some pickups once, it was an unmitigated disaster, I basically boiled them in hot wax, which I then spilt over the guitar. I eventually bought new pups as the older ones looked liked quavers and took it to a local luthier who promptly fell apart laughing when I recited the story to him...the bastard! Lol!