• 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.

Pentode AB1 or AB2?

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Fyi, and fwiw, the particular model I worked on had quite adequate output transformers which did work nicely in fact.

The HF stability I didn't find to be a big problem, the DC bias shift is what killed the tubes... glooooowwww, phfttttt! If there was an HF stability problem on this model, I didn't catch it... heh.

The B+ was less outrageous than that found on a certain California amplifier maker's gear (last letter in the name is "L").
:D

And, at least this one didn't have the screens run into oblivion... I had to check with JC on that amp just to check my sanity because I couldn't believe what I was seeing (popping frying screens at full output level) to be sure that the B+ and screen voltages were not sane. They weren't.

Anyhow, if the French amp's drive circuit was properly set up it actually would have been a nice amp... excellent chrome, not much gold on that model ;)

_-_-bear :Pawprint:

The ironic part of the "L" amp was that owner had to have me change it back to stock so he could sell it!

:cannotbe:
 
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