In article , Howard Haigh
wrote:

"Jim Lesurf" wrote in message
...

[snip]

These show that bi wiring can change the frequency response -
but by only a small amount even when using cables of exceptionally
high series resistance. Hence changes in measured behaviour are
possible. But are they audible in any sensible arrangement?... My
reaction tends to be that if I wanted a change in frequency response
of a few tenths of a dB I'd move my head slightly whilst listening.
:-)


Ah yes - the issue of listening position! Something I've noticed is that
when listening to music if I happen to tilt my head so that I'm either
looking upwards or downwards then there is a discernable change in the
sound - I hear more or less treble. I suspect that the actual shape of
my ears influences how well certain frequencies are heard. So (assuming
that I'm not the only one that this affects) unless we're going to
restrain our heads in some sort of clamp then any comparitive test of
speaker connectivity is more likely than not going to have to deal with
'is my head in exactly the right position to make it a fair trial'


This issue can be tackled. However it tends to require some mix of:

1) The listener(s) trying to put their head in the same position(s) as best
they can when comparing. Thus trying to reduce the effect of head movements.

2) *repeated* listening to the 'different arrangements' being compared, in
'randomised' order with the listener not being told which one is being used
at any time, so only having the sounds to go on. Then doing a statistical
analysis of the results.

Protocols//methods like the above can help to 'randomise' the effects of
differences in head location, changes in hearing physiology during the
tests, etc.

The key point here is that experimental physical scientists have for a
long time devised and used methods to 'randomise' uncorrelated effects
and then use test protocols which can be analysed to show the systematic
effect of the 'target' properties. The snag is that people have to
understand and use these methods, which can be time consuming and require
care and atention.

Alas, many of the reports are along the lines of, "I tried arrangement A,
then I tried arrangement B and they sounded different to me. Thus they do
sound different." For reasons like those above, such reports can be simply
wrong. They may also easily assign as the 'reason' for an 'audible
difference' to entirely the wrong cause. Thus as 'evidence' such reports
are of little use.


and indeed if moving one's head slightly can affect the sound heard then
is there any point in worrying about minor changes that might be
imparted via the speaker cable arrangement?

Indeed. :-) Personally, I stopped trying to chase 'differences' that were
this small some years ago - particularly when the 'evidence' seemed to
consist of unreliable reports of poorly-conducted 'tests'. Simpler to use
the time on enjoying the music. Take such reports in magazine reviews, etc
with a pinch of salt. :-)

Slainte,

Jim

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