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    Building, troubleshooting and testing of these amplifiers should only be
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An "All American" tube Project

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hey I have a surplus of the All amercian five tubes, and I was wondering if anyone had bulit a guitar project using the raw, un-clean sound that these tubes produce, does anyone have any project ideas?

I'm refering to the 50lgt, and the 12sq7 specificly, however if anyone has any idea with the other tubes, i'm all ears
 
I think there used to be a few guitar amps that used the 50L6 and similar tubes,I recall seeing a few,maybe at Triode Electronics,or something. Not alot of power,but maybe you could parallel a couple tubes or something,if you want more power.

One warning,I think most of the amps (and radios) that used these tubes were Line-Op. :att'n: DO NOT build your amp that way,Use a transformer. You don't want your guitar strings to be electrified.:hot:
 
I bought an "Electrolab" guitar amp at a flea market in West Virginia for $5. It uses the 7 pin AA5 tube set. 35W4 rect, 50C5 output, 12AV6 driver, and 12AU6 preamp. I put in some new caps, installed an isolation transformer (don't skip this step they are $11 from Mouser) and cranked it up. It sounds like it is trying hard to be a Champ, but doesn't quite make it. It is a good amp for practice, but it doesn't scream when pushed. I set it asside for future modifications.
 
You will need more gain than the single 12SQ7 can supply. If you have a 12SJ7 (common in this tube set) it can provide all of the gain that you need. The 12SK7 can be used although you will get some distortion. Use the Fender 5C1 schematic and adjust the resistor values to get the tube currents right for the B+ that you are using. (make the 25K in the power supply much smaller, same with the 2 meg on the 6SJ7 screen). The 50L6 will need a smaller cathode resistor, maybe 180 ohms.

http://www.schematicheaven.com/fenderamps/champ_5c1_schem.pdf
 
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