Såhär svarade Phil Zaphod på ppwatt.com:
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AFAIK the 12W dissipation limit only applies to the very old metal can and coke bottle type 6V6s. Later NOS and current production 6V6s are all spec'ed for 14W.
It also needs to be noted that if your amp is cathode-biased, it's common practice to bias well above 70% dissipation - even as high as 100% (with a small cathode cap - below 100uF). This is why sometimes cathode-biased Class AB amps often mistakenly get referred to as Class A amps. What happens with these amps is as they start cranking, the bias voltage at the cathode rises, biasing them progressively colder, so that the tubes stay within their safe operating range.
With JJ 6V6s, no one really knows their true dissipation limits, as they aren't really true 6V6s, but are an iron curtain military tube that are currently being marketed as a kind of 6V6. And it's quite easy to see that they have a larger electrode structure than regular 6V6s, somewhat like 6L6s'. As far as I know the specs on
http://www.jj-electronic.sk and
http://www.eurotubes.com are basically copied from other 6V6 data, for the benefit of Western eyes, and aren't really true for the JJs. I know of people who have run JJ 6V6s at 18W without any obvious problem, but most of us will prefer to play safe and stay with the 14W rating as a guideline."]
Man kan då förmodligen gasa på lite extra om man är på det humöret [8D]
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