So I was in a local multi-dealer consignment shop when I hit the mother load and found what I had been looking for and could feeeeel calling me from the other end of the store - an old tube amp, I needed to scavenge them for my first build since I cannot afford to do it new, and this one is olddddd. Possibly 50's era.
For tubes, it has Two 6L6's (one Ken-Rad and one RCA [metal housing style point to an audio/tv use] ), a Tung-Sol 5Y3-GT/G, Ken-Rad 6SN7GT, and CBS 6SN7-GTA. The four main caps are some nice looking Cornell Dublier "Dwarf Tiger" 600v .3uF. The only other caps are two Cornell Dublier BR845A 8uF 450v, one Aerovox Dandee 16uF 250v, one CD "Beaver" 250v 16uF, and one "Sangamo" 250v 20uF and lastly, a tall 450v 20uF that stands among the tubes.
For the power transformer, we have a Stancor P-6012, and output transformer is a 8W Merit A-2901. The Stancor PT points to this possibly being a Stancor Williamson amp but it does not look like the ones I have seen in the pictures I could find. It has a volume knob, power light and switch, and one channel, I/O's were screw terminals with large finger nuts that bite down (like on the backs of speakers but older). One of the caps had broken off its solder joint, from where, who knows? So I did not try plugging this amp in, did NOT want to ruin parts or die. I would rather like to rebuild it from the ground up for my purposes, as a guitar amp, utilizing all parts possible (can get some good tone with those DT caps, yeah?).
Can anyone help by telling me what the smaller tubes likely did? And by suggesting a circuit to build with these parts (weber?) At this point in my state of learning, I still need to see a layout. I would like a classic's 50's fender sound. I wont be reusing the KR and RCA tubes because they were aimed at reducing harmonic distortion and I actually WANT some of that. If I can use the others, I will. It helps if you can point me towards how to test the PT and OT to be sure they are ok; if you know what lugs to use on the OT, even better. Thank you much.
-Robert
For tubes, it has Two 6L6's (one Ken-Rad and one RCA [metal housing style point to an audio/tv use] ), a Tung-Sol 5Y3-GT/G, Ken-Rad 6SN7GT, and CBS 6SN7-GTA. The four main caps are some nice looking Cornell Dublier "Dwarf Tiger" 600v .3uF. The only other caps are two Cornell Dublier BR845A 8uF 450v, one Aerovox Dandee 16uF 250v, one CD "Beaver" 250v 16uF, and one "Sangamo" 250v 20uF and lastly, a tall 450v 20uF that stands among the tubes.
For the power transformer, we have a Stancor P-6012, and output transformer is a 8W Merit A-2901. The Stancor PT points to this possibly being a Stancor Williamson amp but it does not look like the ones I have seen in the pictures I could find. It has a volume knob, power light and switch, and one channel, I/O's were screw terminals with large finger nuts that bite down (like on the backs of speakers but older). One of the caps had broken off its solder joint, from where, who knows? So I did not try plugging this amp in, did NOT want to ruin parts or die. I would rather like to rebuild it from the ground up for my purposes, as a guitar amp, utilizing all parts possible (can get some good tone with those DT caps, yeah?).
Can anyone help by telling me what the smaller tubes likely did? And by suggesting a circuit to build with these parts (weber?) At this point in my state of learning, I still need to see a layout. I would like a classic's 50's fender sound. I wont be reusing the KR and RCA tubes because they were aimed at reducing harmonic distortion and I actually WANT some of that. If I can use the others, I will. It helps if you can point me towards how to test the PT and OT to be sure they are ok; if you know what lugs to use on the OT, even better. Thank you much.
-Robert
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Pics of the amp:
-R
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
-R
That was BEFORE I stripped it down - because as I said, no way to know what's what or if it's hooked up properly without a schematic or sufficient knowledge of tube circuits. I wasnt going to take any chances with that. I figured out that the Tung-Sol is a rectifier tube, so I'm assuming the other smaller ones are the preamp circuit and the two large ones are the power tubes. It's all making more sense little by little. Personally though, I dont much like all these amps/kits that are assembled on lugs rather than nice and neat on a board with eyelets, a la fender style. It makes it so much easier to understand whats going on.
-R
-R
It's a homemade amplifier in a very tiny chassis. You might consider buying a new chassis about twice as large; you'll thank me later!
The bulk of the parts look quite usable as a guitar amplifier, maybe even as-is. ALL of the capacitors need to be assumed dead; don't waste any time on them. There are gazillions of guitar amp projects all over the internet; the hard part will be picking one. The musical instrument amp section of DIYAudio is a great place to start.
All good fortune,
Chris
The bulk of the parts look quite usable as a guitar amplifier, maybe even as-is. ALL of the capacitors need to be assumed dead; don't waste any time on them. There are gazillions of guitar amp projects all over the internet; the hard part will be picking one. The musical instrument amp section of DIYAudio is a great place to start.
All good fortune,
Chris
Actually, good point-to-point wiring is much easier to follow, because everything is in its place instead of being somewhere else. Also can lead to better stability, so more often seen in hi-fi amps (which can't just slap on big grid stoppers everywhere like a guitar amp, as they ruin the HF response).rhgwynn said:
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