Fabio Berutti wrote:

I suppose that, being able to hear ultra-sounds up to 30 or 40K, our pets
can detect overtones due to instability or bad distortion products much
better than us.
In fact they are annoyed by many "technological" noises, particularly vacuum
cleaners or other small electric motors AFAIK: the bearings'whistle must be
like nails on the blackboard, for a cat.
There are dogs trained to spot drugs or explosives... maybe it is possible
to teach a cat to detect odd harmonics.

One thing is for sure, cats sure don't need to be taught to detect odd dogs ;-)

Miao,

Patrick Turner.



Ciao

Fabio

"Tom Schlangen" ha scritto nel messaggio
...
Hi Fabio,

funny list of testing equippment :-) But i agree.

- European common cat if available (purring is a benchmark
for 50Hz noise.

We have 3 cats @ home and one or two of them sleeping in front
of the speakers while Mozart is playing is a sure sign that
all is okay.

During the breadboard stage of my 807PP, once a cat jumped
up and ran away as I switched the amp under construction on.
Surely enough, it showed at the scope that the circuit at
that time had stability problems at real speaker loads leading
to slight parasitic oscillations. Obviously, the cat noticed
that and didn?t like it :-)

Tom

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