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6L6 SE Stereo HiFi amp DIY Build Help

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Hello!

I am new to this forum.

I am interested in building a very simple basic Stereo Tube amp for my first project with the following specs (open to suggestions);

-single ended (stereo)
-~50W total (25W/channel)
-6L6 power tubes?
-preamp tube undetermined

I saw a good read on a basic 6L6 SE application which matches what I want, but the preamp 6SJ7/6SD7 doesn't look too common, I would like to substitute for a more common preamp tube. The post is here:
DIY Single-Ended (SE) 6L6 / 5881 Tube Amplifier

Any suggestions? An alteration to the preamp in the schematic above to switch to a different preamp tube?

Thank you!
G.
 
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That makes more sense.

You should do some studying of single ended amps. What you want is difficult and expensive, and can be dangerous. There's a reason push-pull amps are so popular. :)

For a first time single ended build, you'll end up at about 2-5 watts per channel. Nothing wrong with that.
 
. ..to get me the 50W easier and cheaper?
Have you ever heard the old saying: "From 3 conditions: fast, best quality, low cost, IN REAL LIFE you can have only 2 altogether" ?
You wanna Hi-Fi and inexpensive? Get ready for a 2-3+ year long project.
Oh, you wanna fast and cheap? That would be just another guitar combo coming out.
Since you have EL34s on hands, better go for 2 in parallel, and you maybe, maybe get like 10 WPC of the good sound.

SE not surely means Hi-Fi. I heard plenty of crappy SEs, and many good sounding PPs. It depends a lot on you understand what you r doing.

EL34 SE amplifier - Google Search
 
KT150 in parallel,might be expensive, but will not be dangerous.

Thank you Kenneth, but that is a $100 tube (website says 70W dissipation? What a beast) I'm a little confused here.

Keeping it simple, a Mono single ended EL34 or 6L6 should yield a ~25-30W output shouldn't it? Or is there a loss with single ended VS Push Pull?

I remember a guitar amp I used to have that was an EL34 single ended, and it was 5W, so maybe that makes sense?

With SE an EL34 will output 5W
And PP an EL34 will output 25W

(more or less) Correct?
 

PRR

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Joined 2003
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SE 25WpC...

Here is a bench-tested idea for 40 Watts SE.

Two KT120 ($108) plus a 1628SEA ($140) and a 370LX ($170).

Double that for stereo.

(A previous plan with one HK257 tube was abandoned as too awkward and dangerous.)

Push-pull needs one more driver tube but the output transformer may be half the size (cost), and the power iron may be significantly cheaper.

Start with transformers you can GET affordably. This probably means "popular replacement" parts. The Dyna ST-70 (two 35W) comes to mind; bias can be adapted to work with 6L6 if you wish. A wilder idea is two OTs from Fender 40 Watt (they will loaf at 25W) and PT from a Fender 100W Twin.... guitar-amp fixers seek low prices for quality iron so may be a buck cheaper than Hi-Fi iron.
 
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