Is anyone able to identify this preamp?

guildguy516

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I currently have a guitar on the workbench that hasn't seen the light of day in 30+ years. I opened it to find this preamp(?) mod. Does anyone know who made this and/or a schematic of it? Thank you in advanced!
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guildguy516

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Do either of you have any more information on this type of circuit, or at least resources that talk about them?
 

Blues Twanger

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Can't really say what type of circuit it is with the goop on in. We could make guesses what the covered components are but that's not diagnostic.
 

Mouth

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There's a 1978 Ernie Ball Stingray preamp on ebay that is coated like that.

Maybe some Ernie Ball instrument?

Do you know if it's for guitar?

If it's worth anything, I wouldn't try to de-goo it.

Is the goo epoxy?

If it's epoxy, I'd use end and side cutters to start nibbling off the epoxy. Jewelers screwdrivers, picks.

That's a lot of work, and a lot of opportunity to potentially kill it.
 

John C

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There's a 1978 Ernie Ball Stingray preamp on ebay that is coated like that.

Maybe some Ernie Ball instrument?

Do you know if it's for guitar?

If it's worth anything, I wouldn't try to de-goo it.

Is the goo epoxy?

If it's epoxy, I'd use end and side cutters to start nibbling off the epoxy. Jewelers screwdrivers, picks.

That's a lot of work, and a lot of opportunity to potentially kill it.

Those preamps are pre-Ernie Ball; EB doesn't epoxy/coat their electronics. That's Leo-era MM preamp on ebay, and the one that @guildguy516 has certainly looks similar to the one on ebay. But it might be an MM Sabre preamp (I think they were different from the StingRay) or even an early G&L preamp from the F-100 or the G-200 from circa 1980-82 or from one of the early G&L basses - Leo did carry forward some ideas from MM to G&L after he parted ways with MM.

From the historical perspective EB bought MM in 1984, after MM went bankrupt and was liquidated (Chapter 7 bankruptcy, not Chapter 11 where the company reorganizes with new financing).
 

guildguy516

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It was in a mid 60s Gretsch that came broken in pieces, it does not look original to the guitar.

I'm guessing it's epoxy, I had an old DiMarzio preamp that was dipped in a tar or rubber compound; it was soft to the touch and somewhat tacky. This feels hard, like plastic, and it's really heavily caked on.

I am far from an expert on these but I did compare them to the examples you stated above: it seems to be much more primitive than any examples I could find of the Ernie Ball, Music Man, and G&L preamps. It is fairly large for an on-board preamp and it uses large components, it feels very "home-made" - if you know what I mean.
 




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