Mini humbucker question

[EFK]

Were the late 60w/early 70s Gibson minis potted? If not, with all that empty space in the center of the one bobbin in which the screws run through, wouldn't that tend to create a very microphonic pickup?

[David Schwab]

Were the late 60w/early 70s Gibson minis potted? If not, with all that empty space in the center of the one bobbin in which the screws run through, wouldn't that tend to create a very microphonic pickup?

None of the Gibson humbuckers were potted until fairly recently, except the lawrence designed pickups potted in epoxy.

Empty space has nothing to do with microphonics. Loose parts cause microphonics. Empty space can't vibrate.

[Mark Black]

I would verify they are very microphonic (at least on my old Les Paul Deluxe).

I can actually yell into the pickups and hear it through the amp.

[EFK]

I guess that's true - air isn't microphonic! However, the pole screws are screwed only into the baseplate, correct? And nothing supports them on their journey up through the big hollowed bobbin, i.e. no wax, so unless the screws are shouldered at the baseplate, tightened-down and not adjusted by a player, there has to be enough slop in the tolerance of thread fit (not to mention the fact that the baseplate is of marginal thickness and thus can't allow for more than a few threads) to bestow upon the screws the ability to 'flop around' a little bit, or at the least, vibrate. I thought this seems pretty microphonic, or potentially microphonic, but having never had a mini hb I am curious! Seems like if you filled that big hollowed bobbin full of wax it would offer support to the pole screws while still permitting adjustment - making it a semi-solid bobbin in other words. Don't know about the tonal effect however.