S888Wheel wrote:
From: chung
Date: 6/17/2004 3:29 PM Pacific Standard Time
Message-id:
S888Wheel wrote:
And, too, a measurable difference is not necessarily audible.
Never said it was. However if there is no measurable differences between
two
signals then there is nothing to discuss. They will make the same sound
with
the same associated equipment.
The problem, of course, is that usually there is a measureable
difference between two components, since our measuring instruments are
so sensitive.
It is not a problem for the instances in which there is no measurable
differrence.
My point is that there are very few instances where there is no
measureable difference, because of the sensitivity of our test instruments.
Care to provide examples where differences are not measureable?
One saves themselves the rigor of doing any further testing. So it
still makes sense to start there.
Only in principle. Not in practice.
Take two cables of the same make, one 3 ft long and one
3.1 ft long. There is a measureable difference. Heck, the lengths are
clearly different. And we can certainly resolve the 0.1 nanosecond or so
in delay.
A delay is not inherently a difference in the signal.
Why not? What about a difference in phase shift? What about the 0.001dB
in level due to the difference in resistance? How about the differences
in resistance, capacitance and inductance?
Heck you can measure
differnt components days apart and there is a substantial delay but the signal
is what it is each time.
No, the analogy is incorrect. One could measure those two cables at any
time, at any place, with any set of accurate instruments and get the
same difference in measurements. These differences are repeatable, and
objective.
It would take an extreme subjectivist, however, to claim that
there is a sonic difference between those two.
It would take a mistake in one's impression to say there is an audible
difference if the only measurable difference is a nano second delay.
There, you are beginning to make the point for me. You are providing a
juegment call that a nanosec. delay does not cause an *audible*
difference. Just like I may say that a difference in level of 0.1 dB is
not an audible difference, but would everyone agree?
Of course, I agree that that delay is not audible, but nonetheless there
is a *measureable* difference.
The difficulty is in agreeing what is an inaudible but measureable
difference.
Another example. Two preamps of the same make, model and specs. One has
an output impedance of 200 ohms. The other 202 ohms. Clearly there is a
measureable difference. Is it audible?
Even if
the comparisons are supposed to be syncronized. If they are not syncronized
there is no measurable difference is there since such delays are irrelevent to
the content of the signal.
You are making a judgment call on what constitiutes an audible
difference. By the way, that is the kind of calls that a lot of the more
scientific-minded have tried to make (like one can't tell differences in
level finer than 0.1dB, or one can't hear above 20 KHz), and a lot of
so-called golden-ear audiphiles do not agree with.
The crux of the problem is in the disagreement on what differences are
detectible via listening only. Past research indicates that level
differences of less than 0.3 dB over the audio band are not detectible
by listeners. Let's be generous and tighten that to 0.2 dB. If we would
agree that this is the threshold of audibility, then we can prove fairly
easily that 99% of the cables and interconnects do sound the same.
I said never said measurable differences were the end, only the start. If there
is no measurable difference it is the start and end. In some cases some time
and effort can be saved.
Very, very few cases. It's better to go straight to controlled listening
tests, IMO.