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List of 2A3 SE Circuit Designs?

Hi Goldleaf, to echo what analog addict said, simple is a good starting place. My daily driver is a RH (alex kitic) style sv83 pentode amp. Cheap tubes, at least when I bought them. Now I will admit, it is a bit over the top with lundahl iron, regulated driver and screens, but it sounds really good, and competes with, and gives very little ground, to a 2a3 set, a couple of 300b sets, or pp 2a3 amps sitting near by. They each have their strong points, maybe a weakness or two, but all sound really good. The simple amps are fun to build, and very rewarding in the sound they will deliver.
 
Thanks for the advice Jim. Analog Addict and I are going to meet and he has volunteered to teach me the basics so I can avoid wasting a lot of motion. You all tube guys are great.

By the way, I have already taken some simple, low cost steps by getting 3 inexpensive, working amps to study and listen to before getting fancier. 2 AK Barter Town buys: a 6B4G SET go-set-go (wired up), a vintage Stromber-Carlson Stereo 8 (7355 tubes) and a hybrid tube/fet amp from Qinpu (the A3 using 6N5 tubes).

Now studying schematics, driver schemes, tube choices and tools of the trade. Fun stuff. I hope those AK members that have followed along have found this helpful and more folks will make the jump to tubes from SS (no need to be either or, I love both).

Cheers.

Now, where did I put that empty extra-large parts box? :D

PS.

It would be awesome if others keep adding other 2A3 designs to this thread as they find them.
 
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A parafeed design from Ken at diy-audio-guide:
2a3-parafeed-schematic.jpg

from: http://www.diy-audio-guide.com/diy-2a3-amplifier.html

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A super cool website for the maniac in you - in German - but really interesting:
http://2a3-maniac.blogspot.com/ translation http://translate.google.com/transla...f=1&u=http://2a3-maniac.blogspot.com/&act=url

Has a lot of Uchida info
Uschi+1+CB.jpg
 
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Very cool Martin.

I've been consulting several old hands on my 2A3 build and this is more wood for the fire. Got some nice old SL7's too. Hmm :scratch2:
 
Goldleaf, IMHO the Rankin srpp with 6072 is a excellent circuit for 2A3, bugle 45 circuit easy adapt to 2A3 (750 ohms cathode resistor and primary impedance 2500 ohms)
 
My 2A3 are old NOS so I'd like to stay conservative to get good life out of them. So far I've got the OPT and power trans (thanks Jay) and 2 tubes and some hefty motor run high V caps for the PS. Now to decide on the tube rectifier to use and then will have to decide about whether the expense of transformer interstages a la Japanese is worth it or not, and stick to a simpler design to control costs.

Yesterday I had the opportunity to audition one of Dennis Had's 2A3 designs (he's the retired designer/partner for Cary Audio) and it was a tuned-to-the-hilt conventional design with no interstage and it sounded heavenly. I got to meet the man at his shop in Cary, NC and he demo'd a bunch of his SET amps. Nice feller' - I was happier than a pig in mud :D
 
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