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On Monday, December 17, 2012 5:41:27 PM UTC-5, Audio_Empire wrote:

Well, first of all, Those "beliefs" that are are saddling me with are not=
"anti-scientific".
There are differences in electronic equipment and I'm convinced that some=
day there
will be tests that will reveal them. I've been in electronics long enough=
to know that
you will never uncover a piece of gear's flaws if your suit of measuremen=
ts keep=20
measuring the wrong thing. Unfortunately, I don't know (any more than any=
one else)
what we would test to account for the differences in modern amps (very sm=
all=20
differences, probably not worth the effort) or DACs (much larger differen=
ces). None
of these things are addressed in any test suite I've seen. Yes, we measur=
e frequency
response, IM and harmonic distortion, channel separation, impulse respons=
e (in
DACs) perhaps we use an oscilloscope to look at square waves to measure l=
ow and=20
high frequency phase shift, but none of those really address things like =
the difference
between the imaging ability of two DACs, for instance, Where one of them =
has a more
three-dimensional image presentation that the other especially since both=
DACs=20
measure similar channel separation (which is so high in digital that as t=
o ostensibly
be, for all practical purposes, beyond the limits of the human ear to per=
ceive that=20
kind of isolation of right and left). Obviously, there is something that =
we humans=20
are not measuring. =20

This is not obvious at all. First, amps and DACs are not mysteries of natur=
e; they are man-made objects. If we couldn't measure their performance, we =
could not design them in the first place. I'm fairly certain that the poste=
r here does not know how to design audio gear, so perhaps it is all magic t=
o him. That would explain his viewpoint.

Second, there really isn't that much to measure. An audio signal, like all =
electrical signals, has only two attributes: amplitude and frequency. (Note=
that an eardrum's movement has the same two attributes.) We can be fairly =
certain that we are measuring amplitude and frequency quite accurately. The=
re's really nothing missing.

Finally, what seals the case is that our two methods of assessing audibilit=
y--measurements and DBTs--agree with each other. That's how science validat=
es itself--by finding multiple confirmations of the same conclusions. If AE=
were right, then BOTH our measurements AND our listening tests would have =
to be flawed, and flawed in the same way. That would be a very strange thin=
g, given that they were developed independently.

bob