Amp Builders?

M

MatchBookNotes

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Soo I have the tube chassis of an old hammond organ, its got 3 el 84s, a 5y3 gt rec and 1 12 ax7...

if I were to repurpose this into a guitar amp would it be advised to basically throw away the circuit board, transformers and the tube connectors/plug-ins? i'm going to have to buy knobs, switches and 1/4" plugs anyways.

Guitar Amp logic = get rid of one 84 and add 1 ax7... what would be a good circuit to put in the chassis?
 
Depending on the output tranny, you could build an 18 watt Marshall type amp possibly. I built one out of an old tube stereo (well, output and power trannies).
 
+1 on the Marshall 18 watter. Lots of people have built that one succesfully. There's a bunch out there on it.

Alot depends on what kind of tone you're after and your level of experience. Do a search on DIY tube amp or build your own tube amp. Check out Schematic Heaven and look at schematics. Below are a couple I found that would work ansd are a bit off the path:

Selmer Futurama
Watkins Dominator
Garnet G250D Sessionman

Some of these oddball tube amps have killer tone that's just different than everyone else's

Anyway, Make sure you understand how to play with these circuits safely. THEY OPERATE ON VERY HIGH VOLTAGES THAT MAY REMAIN EVEN AFTER THEY ARE UNPLUGGED,

Allen Amplifiers has a bunch of info on tube circuits that are worth taking the time to read.
 
cool ..... buil;ding your own amp is a great way to fully understand amps and why they sound like they do.
 
man ..... I have an old Magnavox console mono record player out in the garage ....... maybe I need to check all this out.
I never really thought of doing a conversion like that.
 
Lt. Bob said:
man ..... I have an old Magnavox console mono record player out in the garage ....... maybe I need to check all this out.
I never really thought of doing a conversion like that.
Click to expand...

It can be done. I used an old Webcor record player for my first project. The best amp I made however was based around an All American Five radio parts built to an old DanElectro amp design. The only bad thing about it is there
s no input power trannie in it so it's semi dangerous in that aspect but it sounds fantastic.
 
Post some pictures of your project, I think a class A parallel single ended El-84 circuit would be cool. Good luck with your project and be safe, discharge all caps frequently. I took an old Stromberg Carlson in on a partial trade and I have plans on modifiying it into a Class A guitar amp. I have the Marshall 1974X handwired 18 watter, what a little screamer. I would like to build one of the Ceriatone kits someday. Old tube stuff is the best, I love the smell!

VP
 

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I doubt it's got three EL84's. Likely two EL84's and one 6AU6, which is lots of gain. Or at least that's what little I know about Hammond. It could be stereo, and have four EL84's, but three? That's too bizarre, even for me. Sometimes I just leave well enough alone, and add a 1/4" input. Find out what you have before you go yanking parts out. You may be surprised.
 
 
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Lt. Bob said:
he's a googler ..... it doesn't matter WHAT anyone talks about ..... he'll have pics of it in his 'studio' .......... but he's a pretty good googler ..... I'll give him that.
Click to expand...

I've been told I gotta behave myself. :D
 
Years ago, I had the chance to repair my aunts old tube console, brought that amp chassis home, fed my guitar preamp, single 12AX7 into the HiFi amp (pair 6V6) and cranked it. Nothing to get excited about, sound wise, closer to terrible.

Shortly after that, I copied a marshal phase splitter through another old HiFi amp from the 60's once again a pair of 6V6 and the results inspired me to keep tinkering.

Google long tail phase splitters RG Keen's site has an excellent coverage on that circuitry, take some time to reproduce that circuitry with the 12AX7 and you will be surprised at your effort
 
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