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Bret Ludwig
 
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Default THD claims of audio signal generators


wrote:
snip

Further, NO one here ever made such a claim, save you. The
statement was VERY simpe: ANY solid state amplifier with
substantially more power than 20 watts is going to sound MUCH
better than ANY 20 watt tube amplifier when both are being asked
to deliver more than 20 watts.

That means a 50 watt SS amplifier will do better at 35 watts than
a 20 watt tube amplifier trying to do 35 watts,.



I wholly agree. However what happens when both are asked to deliver
2000 watts? But only for a very miniscule time, and average putting
out, say, 500 mW? Given sufficient crest factor of the material and
sufficiently efficient speakers that is actually a possible (if very
extreme case) scenario. It's the case McIntosh, the purveyors of
specmanship themselves, made, and very well, with the advent of their
first high power solid state amplifier. It is they who IMO have hoist
themselves by their own petard!


A
Class B amplifier is of roughly 50 percent efficiency and so I figured
500 watts power consumption.


So what? What on earth does class B operation have to do with it,
since almost NO audio amplifier since that time ran class B. There
is but one or two such examples, and all are LONG off the market.

Further, what on earth does power consumption and efficiency
have to do with it?


Actually very little, juice is cheap.

A 20 watt Class AB tube amplifier might
at most pull fifty watts,


Just like a class AB solid state amplifier, which comprises MOST
of the solid state amplifiers on the market. The only difference is
the SS amplfiier doesn't have to provide power for filaments..


Yes, that filament power is a deal-breaker. How many watts do four
6L6s and six 12AT7s pull?



Therefore, as anyone can see, the solid state amplifier
has better power efficiency, but, the tube amp at 50 watts pulls less
power than the SS amp at 500 (at full output) or even 80 (I speculated
its quiescent draw.) to do what to the human listener is "the same
job".


This is utter and completely irrelevant claptrap, Mr. Ludwig. We're
not talking about efficiency, we're simply dealing with the fact that
ANY higher power amplifier will sound better than any LOWER power
power amplifier when trying to produce more power than the lower
power amplifier is capable. It has nothing to do with bias class, it
has nothing to do with amplfiier efficiency.

My numbers may be a little off


Your numbers are WAY off and completely irrelevant.

but anyone but you would get the concept.


The concept that is clear is that you made a specific claim which
was wrong:

"Subjectively tube amps of a given specification often (not
always) sound better than solid state amps of better spec.
Russ Hamm proved it in 1973 with his paper which
appeared in JAES and it has not been contradicted."

and now you're making further claims which have only
solidified the fact that you were wrong to begin with.

That ought to be self-evident.


What is evident is either your inability or dogged refusal to deal
with the fundamental tecnnical errors behind your assertions, not
to mention the fact that your cited an article which utterly fails to
support your, ahem, "thesis."


To the extent you never clip your amp, that is true. Hamm et al dealt
not at all with reasons for hobbyists (not studio owners) in 2006 (not
1973) to build their own tube boxes, like the satisfaction of the job
and the appearance of the glowing tubes (which has gotten more than one
audiophile laid more tha once, I'd wager...)