I brought an old Gibson GA20 back to life Sunday

[Scott_F]

This is a cool old early 50's Gibson. Lots of miles on it, filter caps were shot. It was also shorting out a bit inside. Original P12R is headed out for a recone. The amp is 60 years old and the speaker was just crumbling. Believe it or not, the old power tubes were still in great shape. Old Sylvania glass on the 6V6's and 5Y3.

I slapped a Jensen crappy C12N into it for the time being. Amp deserves a better speaker in it than that, but it's all I had laying around. I'm looking forward to the recone.

this is one of those cases where you really don't want to change out too much but this one was an old beater and has little value. I'm still chasing down some noise, but this is a nice one to add to the personal collection. But not before I get the soap and water out on it. It was positively filthy when I got it.

 

[newking70]

Re: I brought an old Gibson GA20 back to life Sunday

 

[Lewguitar]

Re: I brought an old Gibson GA20 back to life Sunday

Way to go Scott - GA-20's are really cool amps. I have one with the original Jensen P12R. If you plug into the microphone input instead of the instrument input it really rips! More gain and drive from the microphone input. The GA-20 is my favorite amp to play a guitar with P-90's through. Lew

 

[jeremy]

Re: I brought an old Gibson GA20 back to life Sunday

is that the minuteman with the transformer pi? i fixed one of those a few years ago for this kid. cool amp for sure! not that loud at all, my blues jr was way louder, but great tone.

 

[glassman]

Re: I brought an old Gibson GA20 back to life Sunday

Nice amps! I used to have one until I lent it out to a "friend" and he disappeared with it. When I got mine, it barely worked. Like yours the caps were shot. The chassis was so rusted that I ended up making a new one and opted to switch to 9 pin preamp sockets instead of the octals that were in there. I ended up changing the circuit to a tweed deluxe type and eventually the only original parts left on it were the transformers and the cabinet. I still have the speaker; dated 1955 (see pic).
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Jeremy, these are miles away from the Minuteman GA20s...totally different animal. I agree the Munuteman amps smoke though, I have an EA19...the Epiphone version of the Minuteman...it rocks!

 

[ES350]

Re: I brought an old Gibson GA20 back to life Sunday

I used to use an early 50's GA20 in the studio a lot; very cool little amp. I did put a Q in it to get a little more honk, though...

 

[Scott_F]

Re: I brought an old Gibson GA20 back to life Sunday

Well, i need to get Jeff to recone this for me and keep it as stock looking as possible. It needs a complete rebuild in my opinion, but I tend to be hesitant about how much I yank.

 

[Aceman]

Re: I brought an old Gibson GA20 back to life Sunday

If you get it working, with minimal invasiveness, you win Scott!

Lew - werd on the mike input and P-90's - RAWK!!!!

And if it sounds good when you are done - who cares what you did to make it go. But I agree, keep it lean as possible for the moment.