In article , Rob
wrote:

Is what is audible all that counts?

No necessarily. For example, a friend has just reported that one of his
tweeters has failed, and his (valve) amp now also sounds bit strange. One
possibility (which he is now investigating) is that the amp may have
deteriorated and instability damaged the tweeter as the amp performance
deteriorated. Hence there are cases where effect which are in themselves
nominally inaudible may end up having significant consequences.

Not a troll (really!) but I'm afraid I've been reading HFW. Without
going in to the merits or otherwise of that organ I'm loosely curious -
not the extent of actually buying any of the stuff they mention to
bolster their argument - by the notion of sound outside the audible
range having an effect on 'the act of listening' - vibrations
especially, and a specific reference to supertweeters and subwoofers.
You can't 'hear a note' but 'sense a presence'.

ULF can affect loudspeakers and amplifiers. Possibly also hearing.

Ohashi and others have also reported in physiology journals experiments
that show effects upon hearing and brain activity of 'ultrasound'
accompanying music.

And I think, from distant memory, that 'Which?' use DBTs and they (their
panel) quite readily find differences between amplifiers, CDPs and
DVDAs - devices of (to all intents and purposes) identical measurement.

I am not sure the above is correct about DBTs. However I'd agree that it is
perfectly possible to hear differences between some amplifiers, etc, in
some circumstances. e.g. differences in frequency response, or when one amp
is clipping/limiting and another is not.

Slainte,

Jim

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