[Andre Jute[_2_]]

Patrick Turner wrote:

And its a moot point if the milspec NOS tubes drawn from military stores
will always sound best.

No reason why milspec tubes or other "special quality" tubes should
sound better. It is true that some were especially designed to be
superior to standard tubes on some parameter, and that the parameter
(higher voltage, higher current, low noise, lower microphonics) may or
may not give better sound if exploited. But many of the improved
parameters were useless for audio applications. Furthermore, the
majority of military or otherwise special tubes were not redesigned on
some parameter, but simply taken off the line and selected for that
parameter, in most cases regardless of other parameters which might
be, and usually are, more relevant to audio tubes. Even if the special
tube was redesigned and manufactured to enhance some audio-sensitive
parameter, you may not want it because it was a limited, handmade run,
and the slightly less audionically-desirable tube from the mass
production will be much more reliable. Finally, among the tubes that
suck in audio amps, I might single out the longlife ones, which were
designed for incredible MTBF but generally (I don't know of any
exceptions) sound like **** because you can't run them high enough and
hot enough to get really low noise.

Andre Jute
18ct ears

And perhaps an even mooter one if you argue that war promoted
development of more musically accurate tubes.

I didn't argue that. I think the 9-pin tubes were, with a very few
exceptions, a disaster for audio. The 12AX7 is and has always been
crap; it's a guitar tube, pure and simple.

In any event, it is well known that the most accurate tubes existed
well before the war: 845, 211, 212E, 300A and B, 6L6 which spawned the
KT66 and KT88 that you still like, and, as a byblow of patent
circumvention, the development of the wonderful EL34 and its little
sister the EL84.

Andre Jute
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