6LU8 push-pull amplifier

[968driver]

This one is my corona 2021 project, with 4 compactron 6LU8 tubes and one GZ34.
It is heavily inspired by a link I found somewhere on the internet:
http://web.archive.org/web/20130531160213/http://www.veiset.net/6LU8/index.htmlOutput transformers and choke are very cheap Chinese ones, power transformer is a Hammond unit.

Sounds really good with my Klipsch Cornwall III speakers.


Best regards, 968driver.

 

[Osvaldo de Banfield]

I love compactron tubes. Cheap, powerful, space saving and high performace. Some RF pentodes with gm of 30mS are pretty fine.

 

[56085]

Nice build!

 

[mashaffer]

After I build a line amp and phono pre (that may take a while) I figure I should do something with some of the 6LU8s I have on hand. My thought was a triode PP with a twist. Instead of using the low power triodes as the VAS and phase splitter I would use them as driver with plate to cathode feedback to set a stable gain for each side and reduce output Z and then use a separate tube for the front end.

 

[Kay Pirinha]

I concur: This is crafted very meticulously!

Btw, in recent times I had to notice that power switches like the one you used, or their equivalents with metal levers, sadly no longer are made by Marquardt😢 .

Best regards!

 

[968driver]

Thanks for the kind replies!
For this kind of amplifiers, I like to use old school switches and pilot lamps, to preserve the retro looks.
Best wishes for all, for a healthy and hoopfull 2022!

Best regards, 968driver.

 

[vinylkid58]

Nice work! That's a very tidy build.

jeff

 

[HeyBill]

What a beauty. Makes me think I should take up a different hobby. 🙂

 

[tomchr]

The 6LU8 and 6LR8 are great compactrons. I built my first Spud using 6LU8. I used the smaller Edcor OPTs and Antek power transformer.

Tom

 

[jhstewart9]

Another 6LU8 Amp, my take on Norman Crowhurst's Twin Coupled Amp.
35W at clipping, Differential driver, CFs driving the power stage. Around yr 2000.

And the HP67, more powerful than a locomotive.

 

[968driver]

Before the push-pull one, in 2019 I also made a single ended 6LU8 amplifier.
Hammond power transformers and choke, Edcor output transformers.

Best regards, 968driver.