Introducing a New Horse to the Stable
OK, OK, I will bite! Minor rant to follow:=20
Tube vs. Solid State on reliability:
There are not so very many 60-year old components in operation these days u=
nmodified since-new. My oldest tube item turned 100 this year and likely wo=
rks better than when it was new based on a better understanding of antenna =
systems, optimum tube voltages and so forth. Other than moving parts (CD pl=
ayer), the newest component in my office system was made in 1963. The syste=
m runs 9 hours per day, 5 days per week. Oh, and the tubes are original as =
well.=20
On the other hand, and given my hobby, I see a large number of SS component=
s that have blown transistors, exploded capacitors and much worse, irrespec=
tive of age and source. The well made, well designed stuff is serviceable, =
distinguishing it from the rest of the garbage out there.=20
I would make a fairly apt comparison: A tube amplifier is much like a mid-l=
ast-century Mercedes or VW - few things were self-adjusting, and they requi=
red regular and attentive care-and-feeding. With such, they were good for s=
everal hundred thousand miles of reliable service. A contemporary Ford, Cad=
illac, Plymouth would be considered remarkable were it to survive 100,000 m=
iles without heroic measures. Might run very nicely when running, but that =
would be your basic solid-state device in comparison.=20
Put simply, they are different beasts designed with different things in min=
d, but for the same basic purpose. That one is or is not "BETTER" than the =
other is not relevant to the purpose in either case.=20
Now, when I here things like "Zero global NFB" and "Critically matched comp=
onents", I can smell the snake-oil from a great distance, even the 10,000 m=
iles from here to Australia. I am sure that process also contains descripti=
ves of "interconnects" rolled on the thighs of virgins on Walpurgis Night..=
..=20
Note that even "critically matched" solid-state components drift after a ve=
ry short period of time in-service. All of them, such that that "less than =
1%" is meaningful for perhaps 12 hours or so.=20
Being as this is a hobby for me, I get to try things that are otherwise unp=
roductive, unprofitable or impractical. Such as shotgunning a device with s=
ingle-value capacitors and then comparing it to the same device with carefu=
lly screened and matched caps. Or matching driver and output transistors an=
d comparing to a similar device with disparate values. Guys and gals - you =
would be seriously shocked to discover how little difference some things ma=
ke that the ALL-SEEING, ALL-KNOWING gurus will tell you are critical. Often=
no difference at all.=20
Peter Wieck
Melrose Park, PA
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