[Audio Empire]

On Tue, 1 Mar 2011 14:05:25 -0800, Arny Krueger wrote
(in article ):

"Audio Empire" wrote in message


I can't answer that except to say again, that there is no
reason to expect that any two DACs would sound the same.

Seems very unscientific. Appears to totally reject the well-known and widely
accepted belief that the ear has thresholds for perception of noise and
distortion.

No, my statement does not in any way reject that premise. However, it is
being found that these thresholds are not fixed and can not only vary greatly
from individual to individual but can be affected in a single individual by
levels of stress, and other psychological variables of human emotional
response.

Many examples in the scientific literature where even very dissimilar DACs
and ADCs were compared without positive results.

While that's true, it doesn't, in and of itself, prove anything. Remember the
scientific axiom: "absence of evidence is not evidence of absence". While DBT
results are useful (especially when a positive result is returned or when
negative results proves a physical or mathematical prediction), negative
results that do not support an otherwise provable result, are just that;
negative results.

The analog stages are different,

So what? I can build a 100 different analog buffers that can't be
distinguished from each other in a proper listening test.

See above.

the pre-D/A data handling is different (as in simple and cursory in cheap
DACs, and very sophisticated in expensive ones).

Wrong on several counts.

One is that the industry standard chips for doing this sort of thing are few
in number, and the more popular ones appear in both very inexpensive and
very expensive equipment.

I invite you to look at a DCS Scarlatti or Paganini DAC or an Antelope Zodiac
Gold DAC, and while you count the number of "standard chips" employed, take
a look at the non-standard and proprietary circuitry involved. I would like
to especially direct your attention to DCS' proprietary "Ring DAC". It is not
a Delta-Sigma DAC, it is not a single-bit DAC, or any other "standard chip"

Anybody who can't hear the difference between a Benchmark, an
Antelope, and a DCS Scarlatti DAC/Master clock combo,
simply isn't paying attention.

No, they're simply doing good bias-controlled listening tests.

That's an assumption not in evidence - on several fronts. First, you are
assuming that proper bias controlled tests haven't been performed, and
secondly you are assuming that a null result (or even lots of null results)
is definitive. No reputable scientist would ever make that mistake.

Here's a link to a JAES paper that makes many relevant points:


http://hlloyge.hl.funpic.de/wp-conte...ility-of-a-cd-
stan
dard-ada-loop-inserted.pdf

OK, maybe I missed something, but it seems to me that this paper addresses
the audibility of SACD/high-resolution DVD-A against 16-bit/44.1 KHz CD
quality playback. I don't see where it addresses what we're talking about at
all - even peripherally. It makes me wonder why you bothered to post the URL?
Thank you though, It made for interesting, albeit irrelevant, reading.

At least Meyer and Moran (the paper''s authors) understand well enough the
worth and limitations of DBT tests' ability to ascertain sonic results to
print the following disclaimer: "Now, it is very difficult to use negative
results to prove the inaudibility of any given phenomenon or process. There
is always the possibility that a different system or a more finally attuned
pair of ears would reveal a difference. But we have gathered enough data,
using sufficiently varied and capable systems and listeners, to state that
the burden of proof has now shifted."

IOW, they are acknowledging the difficulty of proving a negative. Like I said
above, DBT is useful in confirming an outcome that is predicted by physics
and maths (such as that interconnects and speaker cables have no effect on
the signal that they are passing at the lengths in which they are typically
used) and less useful at making determinations about unknown qualities (like
amplifier sound) where a null result can be less than informative.