Tube DIY Asylum

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RE: My experience is the opposite

Posted by Tre' on June 23, 2017 at 18:48:40:
" i could hear the difference between the power triodes of these vs power pentodes of 6550, KT66, EL37, KT90, KT120 power tubes and the differences are small. "

That's interesting. I hear big differences between triode wired beam (or pentode) power tubes and DHTs.

Pentodes and beam power tubes wired in triode are far less linear than true direct heated power triodes.

"DHTs have about one-half to one-third the distortion of triode-connected pentodes" Lynn Olson.

But everything I build is free of loop feedback. I would think a little NFB would bring the sound of the two closer together.

Tre'