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Tim Williams[_3_] Tim Williams[_3_] is offline
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Default Tube mono-block amp with SIX 6L6 outut tubes

"Big Bad Bob" wrote in message
...
sounds like a gimmick. Tube plate/cathode currents are just way too small
to properly drive a speaker without an impedence matching transformer.


So what, nothing comes out?...

They were definitely below the maximum power point (at clipping), if that's
more accurately what you meant.

6AS7/6080, 6S33S and the other regulator tubes have peak cathode current in
the ballpark of an ampere, so a modest number of tubes offers a modest power
output, say 20 or 40W, preferably into a higher load like 16 ohms. The
efficiency is poor, with more heat dissipated in the heaters alone, than
delivered to the output.

If you put dozens in parallel, the efficiency keeps going up as you get
closer to matching, but now your whole system consumes multiple kilowatts...

There was also the Philips "SEPP" with a pair of EL86? driving a 100s-ohms
voice coil at good efficiency, but those speakers are so rare that this is
practically a unique case.

Tim

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