[Audio_Empire[_2_]]

On Tuesday, December 18, 2012 7:03:31 AM UTC-8, Arny Krueger wrote:
"Audio_Empire" wrote in message

...



There are differences in electronic equipment and I'm convinced that some

day there

will be tests that will reveal them.



That the equpment is different is fact. The question at hand is not about

that fact. The question at hand is about the audible significance of those

differences.



The use of audio gear seems to be pretty straight-forward and simple. We

apply audio signals to audio gear, turn it into sound in listening rooms

using loudspeakers and headphones, and listen to it.

If it were that easy, there would perfect systems which would create
perfect facsimiles of the actual recorded event. I've never heard anyone
say that such-and-such a system was indistinguishable from the real
thing. Nor Have I ever heard anyone say that they mistook reproduced
music for live music. The most convincing I've ever heard was a pair
of the recent Wilson Alexandria XLF speakers driven by a pair of VTL
Siegfried II 800 Watt/channel power amps and a dCS Debussy CD
rig. It was good, I've never heard a pair of speakers load a room like
the XLFs. Impressive, but even with really good source material (like
my own recording of the Stanford University Jazz orchestra (made with
a single, big capsule stereo mike) it never fooled me into thinking that
it was anything but a very good recording, and the commercial stuff
they were demonstrating with in that hotel meeting room was even less
convincing. Si suggest that you revisit your statement that it's simple.



The symmetry between listening tests and listening to music for enjoyment

can be as complete as we have the patience to make it so.

That's true, but the word patience is the operative one here. Nobody
running these tests seem to take into account that soundstage
and imaging of say. a DAC, would be better served if the source
material actually had some real sound-stage engineered into it.
Frankly, due to the taste of most of the listeners involved in these tests,
good source material, material that would show things like
differences in soundstage presentation, generally aren't used. Also,
the people conducting such tests are so hung-up on instantaneous
A/B comparison that they never stick with one DUT or the other
long enough for the listening panel to focus-in on any differences
that aren't instantly recognizable.

It is ironic to me that much of the so-called evidence supporting the

existence of mysterious equipment properties that elude sophisticated

testing is obtained by such crude means. It even eludes all known attempts

to duplicate the crude means while imposing basic a few basic, simple bias

controls by the least intrusive means found after extensive investigation

and experimentation.

Ironic is it? I'd use another word, I think.



If you are talking about technical tests then the solution to our problem

can be found in multivariate calculus. It is a mathematical fact that any

system with a finite dimensional state can be fully analyzed. An audio

channel has two variables being time and intensity. It is very simple.

Mathematicians have analyzed these two variables for maybe 100 years

(analysis acutally started no less recently than with Fourier).

Like I said earlier, if it's so simple, how come NO stereo system, regardless
of price or acoustical setting can create a convincing facsimile of a real
performance playing in a real space? If you've ever been to New Orleans
and walked down Bourbon Street on a warm evening, you will have noticed,
as you walk down the sidewalk passing the open doors of this establishment
or that establishment, that you can tell in an instant, without even seeing the
source, in which establishments live music was playing, and in which
establishments the music is canned. The worlds finest stereo system, one
with state-of-the-art BIG speakers costing as much as a new Ferrari, simply
cannot convince anyone that the sound is real.

I've been in electronics long enough to know that

you will never uncover a piece of gear's flaws if your suit of

measurements keep

measuring the wrong thing.



That's a truism, but without more specifics it is just idle speculation.

So "trisim" = speculation?


Unfortunately, I don't know (any more than anyone else)

what we would test to account for the differences in modern amps (very

small

differences, probably not worth the effort) or DACs (much larger

differences).



What differences are we testing for - things that only show up in sighted

evaluations or evaluations that are semi-, demi-, or quasi controlled?

Doesn't matter, but they do show up in carefully controlled tests as long as
the source material is of sufficient quality to allow these differences to be
heard, and as long as the testers aren't looking ONLY for differences that
reveal themselves in quick A/B comparisons.




Once we learned how to do reliable listening tests back in the 1970s there

have been no mysteries - what we hear we measure and vice versa given that

we measure enough to be audible.



As others have pointed out one of the first casualties of reliable listening

tests was the hysteria over slew rate induced distoriton.



None of these things are addressed in any test suite I've seen.



None of what? So far I see no actual description of something with hands and

feet.

This is your selective editing at work, methinks.

Yes, we measure frequency

response, IM and harmonic distortion, channel separation, impulse response

(in

DACs) perhaps we use an oscilloscope to look at square waves to measure

low and

high frequency phase shift, but none of those really address things like

the difference

between the imaging ability of two DACs, for instance,



Yet another audiophile myth that dies a quick death when you start doing

adequately controlled listening tests.

That's just it. Mr. Kruger, IT DOESN'T die either a quick death or a slow one.
Also what it doesn't do is show up immediately on quick A/B tests. It also requires
that the recording used in the evaluation actually have some imaging specificity.
Most of the DBTs where I've been a listener, are pop, rock, and jazz recordings
which are studio creations, that, at the very best, are all multimiked, multi-
channel affairs and at worst either have no acoustic interments in them or,
have been Frapped! No imaging specificity there!