Gibson GA-25RVT

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Structo
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Joined: Wed Oct 17, 2007 1:01 am
Location: Oregon

Gibson GA-25RVT

Post by Structo »

A friend just picked up a GA-25RVT amp and he doesn't know what speaker impedance these have.
I looked around and couldn't find it mentioned.

Anybody familiar with these amps?

I am still exchanging emails with him about it.
He didn't mention if it came with a 15" Jensen or JBL yet.
Tom

Don't let that smoke out!
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Structo
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Joined: Wed Oct 17, 2007 1:01 am
Location: Oregon

Re: Gibson GA-25RVT

Post by Structo »

He says it came with a 10" speaker, not sure if the baffle is new or what.

It seems a lot of these Gibson amps had changes made that are not reflected on the schematics.
Tom

Don't let that smoke out!
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Phil_S
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Location: Baltimore, MD

Re: Gibson GA-25RVT

Post by Phil_S »

Probably an 8 ohm load. But why guess?

Pull the power tubes, disconnect the B+ supply to the CT, jumper the filament supply to the plates, and see what voltage you get on the secondary. Calc the turns, square, assume pair of 6V6 are 8K. Five minutes work will confirm the right load.
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