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Tube Single Ended Triode Questions??

Why can't SETs be built with more power and able to drive a bigger range of speakers? I know the 300B tube can goto 10 Watts or so, and the 2A3 in only 2W, but why can't they do an amp that is like "single ended parallel" with several amp stages in parallel? Or, why can't tubes be used like EL34, 6550 and KT88s (I guess these are known as power tetrodes) and make higher power SE amps? I guess the idea behind SETs is to avoid splitting the siginal into push-pull and they are class A, but you give up a little S/N ratio with a SE circuit - is this correct? Are some tubes too noisy to run single ended, or can only a portion of a KT88 be used in SE mode?

Also, the output transformers- is this really what seperates okay from great SETs? Are quality transformers what makes them so expensive for what appears to be a very small parts count?

I have some question for latter about SE -vs- Balanced preamps too - is it a simialar trade off to SE/BAL amps, but I will save that for latter.
6550c

Showing 1 response by onemug

onemug
784 posts
 
I use a pair of SET Cary 805AE's to drive my Maggie 3.6's occasionally. Cary claims either 50 or 70 wpc, depending whether you use the 845 or 211 output tube (1 tube per channel, no paralleling). I do 90% of my listening at low to mid volume levels and normally use Pass XA monos to drive them but I love the sound of SET's and took a chance on the Cary's working out. They do to my satisfaction.

I seem to remember ASL making a single ended KT88 amp some time ago. I think it only put out 12 or 15 watts though.
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