Music man transformer

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Today i got 3 NOS transformers marked Music man.

Stacking height is about 1.5 compared to the mainstransformer on my JCM800.

Anyone got a clue to what model theese goes into.

Size indicates a 100+watt amp

musicman.jpg
 
If they´re in demand to make any amps return from the dead i´ll happely pass them on.

Can´t post on that forum Trout but please direkt them here or make a post with the picture.

They seems to be 115/230 input so should fit any country.

I´ll try to hook them up during weekend to let them reveal what voltage they´re putting out.

They´re from a parts store that had it´s highs in the 50-60s and then slowly faded away.
 
I like the idea of going to the Music Man forum.

180v does sound very low. Quite a few MM models did not have CT on the high voltage winging, they fed it to a voltage doubler. They ran the B+ for the EL34s at 700 volts. For teh soldi state front end, they had +/-15v rails, and I suspect that 29v may have been for that, rather than bias. But 180VAC won;t get me to 700v DC right away. On the other hand the 6L6 models were only running at 500v, so maybe.

SOme of the models drove the power tubes through their cathodes, and as such had no bias supply. First grids sat at about +25v.

Let us know what you find out.
 
Browsed the schematics and didn´t find something that matched.

Most amps i found was hybrid this i think is a pure hollowstate transformer.

If i switch primary and HT i get 280v for HT but the filament goes up to 8V

If nothing else i can use it for a DIY and put in a filament reg.

280 and a voltage dubbler should work fine for an 100w amp.
 
8V on the filament winding? What does that 8v do when you load it like the amp would? FOur EL354s would draw 6 amps, and that might just drag it back down where it belongs.

I think those schematics included wire colors, at least some did. That might be a clue to which winding was which, since there appears to be some ambiguity.
 
You might be right on the 8v drop, but 2v drop seems a lot i´ll give it a try and hook it up to some load resistors.

I suspect that this is some kind of aftermarket unit.

They appear to be well buillt.

All schematics i found had CT windings and different colour coding.

There were lots of bits and pieces in the basement of the store theese came from.
 
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