[Arny Krueger]

"Eeyore" wrote in
message
Arny Krueger wrote:

"Eeyore" wrote
Arny Krueger wrote:
"Eeyore" wrote
Arny Krueger wrote:
"Eeyore"
wrote

You're aware that I've designed a fair number of
successful commercial designs I believe.

Yes, but you seem to be very worried about things
that just don't happen with the modern SS amps I've
tested, even fairly rugged cheap locomotives like
the QSC USA series.

The QSC USA series is a COMPLETE HEAP OF CRAP and
illustrates many classic design flaws and is a good
example of just how NOT to build a high performing
amplifier. The USA series is also most certainly not
*modern* by any reasonable understanding of the word.

If you can't hear the flaws of a USA series you must
be completely deaf.

Mere assertions with no supporting facts provided,
neither theoretical or experimental.

From listening.

Sighted evaluations.

Nothing explicitly wrong with those especially when the
result isn't subtle (which it wasn't). We are talking
about GROSS differences here.

All the golden ears say that. I've been hearing about gross differences due
to different interconnects and magic capacitors for about three decades.

If I take a Ferrari out for a drive and then a Yugo and
come back and say the Ferrari was faster is that to be
denied because it was a sighted test ?

Irrelevant to anyhing said so far.

I'm aware you dismiss any listening tests that don't
agree with your opinion.

If you mean that I tend to dismiss all listening tests,
irregardless of outcome, that aren't done in a
professional manner, then I'm guilty as charged.

Possibly you dismiss ALL
listening tests that can't be replicated by deaf people
using the ABX method too ?

What's this deaf people stuff Graham? You're talking
trash! :-(

What's the THD of a USA series
at 100mW and 1W for example and what does the distortion
analyser output (Self's Figs 14 a,b ,c ) look like (or
provide a spectum analysis).

Tell us Graham. You're the professional engineer.

Why would you believe my measurements, Graham. In your
view, I do ABX tests with deaf listeners. If I'm that
idiotic, why believe my measurements?

Bottom line Graham, you're running true to your - lots
of lip, lots of crazy accusations, and no reliable data.
:-(

I'm not one for making great claims for being 'golden
eared' and all that but it is a FACT that certain
people's hearing has more acuity than others.

No doubt. Young well-trained listeners have been trouncing me in ABX tests
for years. OTOH I can reliably detect all sorts of things that untrained
listeners of any age can't hear. One other advantage of training is that I
can relate what I hear to the right frequency band very well.

I've
recently been involved in tracing low level buzz and hum
in a studio control room along with 2 other techs and I
was the only one of us 3 who could reliably hear what the
mix engineer was complaining about AND use that to trace
and eliminate the source.

I have a headphone amp with lots of gain reserves for tasks like that.

Any testing using a panel will seriously degrade the
likelihood of detecting REAL audible differences by
diluting the numbers whose hearing is up to the task.

Depends on how you make up that panel.

And ABX testing in its very philosophy seems to be more
about detecting differences that everyone can agree they
hear rather than differences that only a few can hear.

Nonsense. The results of an ABX test self-administered by one listener can
be definitive. That's one reason why we invented ABX comparators - so that
we with trained ears could obtain reliable results all by ourselves.

Remember that when I started out with ABX I was in my 30s, and my hearing
and that of many of my friends and associates was far better than it is now.
The way us old dudes get the most sensitive results is by working with young
listeners and training them to hear small differences, and then basing many
of our conclusions on what they hear.