In article , Rob
wrote:
Jim Lesurf wrote:
In article , Rob
wrote:

I simply don't get this. I've been using 5 SS amps of late (Quad 405,
Rose power amp, Cambridge AV, Behringer A500, and that within a Pure
mini system), as well as others on and off over the years, and I feel
each has 'a sound of its own'.

The problems with the above are as follows:


[snip]

2) Yet when people do level-matched comparisons and avoid obvious
snags like clipping *and* have only the sound to rely upon, the result
is often that they can't reliably tell one amp from another.

FWIW A number of tests have also shown that people tend to hear
'differences' even when the same system is used in the same way.


Yes, I agree. DBT is not a trivial thing though,

I was not specifically referring to DBT methods. Just to ones which have
sensible test conditions - e.g. level matched - and where the listener was
having to rely upon the sounds alone.


and surprisingly (to me) there doesn't seem to have been many rigorous
tests to underpin the 'little if any difference' thesis.

You would need to clarify what you mean as I am unsure of the point you are
making.

The situation as I understand it is that appropriately performed tests
often show no sign of the listener being able to distiguish. In some cases
they do throw up various effects which may be due to methodology flaws. The
tests I have in mind were not to see if the differences were 'little', just
to see if those listening could actually show any relable signs of being
able to hear *any* audible differences.

I am therefore unsure what purpose the tests you refer to would have. Is it
to simply establish that two units *do* produce different results at a
level so small as to be inaudible? If so, I'd suspect that simple
measurements would confirm that differences exist in many cases. Just that
people show no sign of being able to hear them when tested.

Slainte,

Jim

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