In article , Bob Latham
wrote:
In article , Dave Plowman (News)
wrote:

Surly you've heard the results of a digital stream being 'lost'? On
DAB or FreeView? It doesn't effect any of the analogue parameters
'depth' 'space' 'positioning' etc. It's usually a bloody great hole
followed by a chirps and bangs as things attempt to sync up again...

You'll effect these things by reducing the data rate. But no cable
can do do this.

I'm almost in full agreement with this but due to lack of knowledge
there are still a couple of "maybes" in my head.

A cable carrying a digital data stream presumably square waves, will
distort the shape of that wave. Hope we have no argument so far.

Bear in mind that "square waves" are a convenient mathematical fiction. In
reality the signal can't have discontinuities which change the level in
zero time as this would require an (impossible) infinite bandwidth.

Thus a real receiver can't, and does not work on a basis that requires this
- otherwise it would never work. :-) Good engineers may be lazy, but they
aren't daft. ;-

In principle, you can invoke all kinds of 'effects' that, due to the
imperfections of real systems and cables, 'might' affect the results. A
common example, beloved of magazine reviewers in this context being
'jitter'. Yet in practice, when people measure this they tend to find that,
below a fairly high level, no-one has shown they can hear any resulting
changes when tested solely on the basis of the sounds...

Hence this seems to be yet another example of an area in audio where some
reviewers and sellers blow up something out of context in order to give
them a 'scientifically plausible reason' for the differences they say they
can hear - yet often have not demonstrated are audible to them solely on
the basis of the resulting sounds.

You will in a similar way find many 'reviews' which quote values and use
them to try and support comments by the reviewer. Unfortunately, some
knowledge on the part of the reader may be required to distinguish 'fact
from fantasy' in such reviews on occasion...

Slainte,

Jim

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