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Hoffman Amps Forum image Author Topic: Vintage Optimus Alabama PA Amp conversion ideas.  (Read 1638 times)

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Offline FranciscoPerez

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Vintage Optimus Alabama PA Amp conversion ideas.
« on: September 02, 2020, 03:06:39 am »
Hello everyone,
I recently laid my hands on an old PA amp built on the 60's. It's an Optimus Alabama, 100W made in Spain.
It's in mint condition. Change the power cord, e-caps and a broken el34, and it'd be good to go.

Anyway, I'd like to convert it for guitar use. It uses 3 ecc83 and 4x el34 tubes. What do you think? Would this be a good candidate for conversion?  What guitar amp circuit would you recommend?


Thank you,
Fran




Offline Latole

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Re: Vintage Optimus Alabama PA Amp conversion ideas.
« Reply #1 on: September 02, 2020, 03:33:05 am »
IMO you may just need to replace some caps values to make the amp more guitar "friendly"
Signal caps and cathod bypass cap

Values ? A la Fender or a la Marshall or........
« Last Edit: September 02, 2020, 04:43:26 am by Latole »

Offline FranciscoPerez

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Re: Vintage Optimus Alabama PA Amp conversion ideas.
« Reply #2 on: September 02, 2020, 04:33:34 am »
Thanks Latole.
Yeah maybe some minor changes would be enough, sounds like a fun weekend project.  :icon_biggrin:


It would be nice to make something different this time, though, since I already built a couple of Marshall and fender circuits and a Soldano, (Marshall 18W, Marshall JCM800, Soldano SLO100, Fender 5f2a, Fender 5e8a...).


Something to pair with a strat or tele, for blues/rock. I'd probably have to add a ppimv or similar, since this will be played mostly at home.

 


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