Sander deWaal wrote:

Stewart Pinkerton said:

How about it Stewart?
What properties do you think a good tube (valve) amplifier should
have?

At least 100 watts output, with 20-20kHz THD and HF IMD of less than
0.1% at 80% of full output, and a *power* bandwidth of 15Hz to 50kHz.

OK, I think that could be done.

And do you think you could design an amp according to those lines?

Anyone can. The trick is finding a really good output tranny. The
basics of paralleled KT66s in an ultra-linear configuration remain at
the heart of all truly top-class valved amps. This basic design has
been around for at least fifty years.

Ah, but there's more than just the power stage to worry about.
How about the choice of a phasesplitter, input circuit, choice of NFB
path, choice of components, the power supply..........

I think there's a lot more to be said about a tube amp than just "6
paralleled KT66s in push-pull" ;-)

Finally, are you willing to take up on this challenge?

It's not much of a 'challenge', the design work was all done many
decades ago. Besides, why would anyone go to such trouble and expense
to make something which can only ever be a pale imitation of a decent
SS amp costing a quarter as much?

I'm trying to get you to think about designing a tube amp.
It's a start if you just described what circuitry you would use.

After all, dissing tube amps should be based on actual knowledge of
the subject, shouldn't it? ;-)

He may not have time.
By this time next week he might be Pope Angus the First.

You aren't confusing me with Angus Pope, by any chance? :-)

Just heard they have chosen Ratzinger.
Another dark middle ages ahead.................

I don't give a rat's arse what the Catholic Church does with itself.

It sure **WILL** be a dark age for r.a.t if we insist
that its silliest, rudest and most disrespectful contributor, who hates
vacuum tubes
be compelled to design a tube amp.

I see so purpose in enchoraging a fool.
Stewpid Oinkerton is better left well alone imho.

Patrick Turner.





--
Sander de Waal
" SOA of a KT88? Sufficient. "