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Original Message

RE: Thinking about running my non-OTL Circlotron again

Posted by Tre' on August 18, 2011 at 12:38:41:
"As you know, Tre', this is not "news"."

I know, I was just "sharing".

"The assymetrical wave form out of the OTL circlotron has been described before. To me, the surprise is that you like the sound WITH the transformers better than without them."

That asymmetrical wave form is the cause of harmonic distortion but because this is a push pull amplifier the wave forms from each bank will be combined and most of that harmonic distortion will be "covered up".

But it won't all be covered up. If we start with clean wave forms from each bank of output tubes then there is no high harmonic distortion to cover up in the first place.

The output transformer gives the output tubes a higher impedance load line (more horizontal), that's why there is so much less harmonic distortion.

The output transformer I use is one of the best ever made and whatever harm it's doing is way less than the harm from the harmonic distortion caused by a vertical load line.

"In the commercial market, this is called a BAT amplifier. How does your version differ from BAT's, except in that you may not use a toroid, and they use 6C33Cs, not 6AS7s? Thanks."

I would have to see the BAT schematic to answer your question.

The 6C33C is not very linear at all and I would not use it.

Tre'