• WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.

801 low power SE amp

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Thanks guys, I'm having fun. Next up, it's mirror image for the other channel (4 channels per side, two tube, two ss - at least for now).

Yes those are Russian teflons, but the iron is from Electra-print. The amps sound nice to me, but I have not compared different caps, etc.. Only so much time, and so many things I want to do. So I rely mostly on semi-informed guesswork - informed partly by reading here. I take my shot, and if it sounds good, I move on to the piece of the project. When I get this all done, I may try some fiddling with components.

Sheldon
 
Both amps finished for a bit now and sounding very nice. I was getting some left/right crosstalk, so I looked over my work and made two changes. On the amp schematic (one page back), the bias for the 801 is applied between the two 100k resistors in series to ground. In Steve's original schematic, there is a 2.2uf cap bypassing the lower resistor. I added this cap and it reduced the crosstalk, but didn't eliminate it. So I split the bias supply at the last RC (it has an (CRCRCRC), by adding a second parallel RC for the final section. That completely eliminated the crosstalk.

Sheldon
 
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