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    Building, troubleshooting and testing of these amplifiers should only be
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Dual Rectifier Tubes; Would Matching Be Better (or even matter)?

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In a guitar amp anyway, no one would bother. What problem would it solve? Amps like certain old Fenders or contemporary amps like the Mesa don't match them, they don't even match output tubes.

In circuit, if one side has a slightly higher or lower equivalent resistance or just conducts more or less than the other, all that results is your ripple is a slightly uneven sawtooth instead of just perfect. In any case, that ripple is filtered out by the B+ filter caps, and in a push pull amp (I can't imagine a dual rectifier single ended amp) the power supply ripple tends to cancel anyway.

Just my opinion, but I don't see any value in doing that. Well, other than some sort of marketing hype. But then we are venturing into the world of people touting balanced 12AX7s for split load phase inverters (which use only one triode).
 
Hi Enzo... thank you..

No marketing hype... just me wondering..
(especially since I'm about to buy a few more rec tubes)

It's not a guitar amp... it's a (presumably) hifi amp..
It actually IS single ended... LOL..
Sounds VERY very nice BTW.... especially with the Soviet EV rectifier and power tubes, plus JAN-Sylvania 5654s....

It's this one:
Douk Audio 6J1+6P1 Vacuum Tube Amplifier Stereo Class A Single-ended Power Amp | eBay
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As far as ripple is concerned...
It's always been my understanding that it's very desirable to, and designers are always striving to... eliminate as much ripple as possible...

But hey... it was a question..
If I knew the answer, I wouldn't have asked it.........

Cheers,
Greg
 
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The only thing besides ripple that might concern is magnetic saturation of the PT's core, caused by unequal DC current flowing through both secondary halves. BUT: Two way tube rectifying is, or has been, common since about hundred years, and I've never heard from issues of that kind. So it is most probably an academic one 🙂.


Best regards!
 
Transformer secondary winding resistance is often different for HV-0-HV windings.

So if you were really keen, and you had a spectrum analyser, you could measure the mains fundamental frequency ripple level on B+ supply, and then swap HV windings over to see if fundamental frequency voltage reduced or increased. Then look for same frequency artefact on output of amplifier - but that is likely only at idle, so not a proper test.
 
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