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    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.

2a3 DC coupled

Hi, I've made a DC coupled 2A3 using stacked power supplies. I think it's easier since both supplies are independent so you can tailor them as you like
The drawback is of course you need to use 2 power transformers or have a custom-wound transformer with 2 high voltage windings.
Reza
 
Also, the freq response on the plate of the input tube will not match the output side of the autoformer... nor in terms of phase...

Take your time and read the whole thread. If I´m not mistaken Dave made some IRL measurements on dual-chokes too.

One can see the concept as a refined DC-coupled variant on Magnequests Seth 2A3PP/6C45 S-240.
 
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Hem ... yes ... I made many variations of that kind of amp. CCS, stacked supplies, zeners/gas tubes ... a couple examples in the schemos below. I didn't build actually the amp with the 300B you see in that schematics but a couple have been built with 45's by friends of mine. more info are buried in discussions over the MQ forum, you need to change and adjust things but the basic idea is always the same

link to MQ forum

my latest amp, differential into differential, sounds better tho
 

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This will work, it doesnt have single thing why it wouldnt work.
Only I would use different tube than 4P1L as the first stage. It has too thin tone for me and I dont think tube with gain 9 will drive the 2A3 fully. You will need a preamp