On 05/07/2021 06:55 PM, Fred Cisin via cctalk wrote:
Hmmm. If they ever use single phase, instead of 3 phase,
. . .
A4 (A above middle C) is nominally 440Hz, but not
everybody agrees.
NY Phil uses 442, Boston uses 441, and many argue for 432.
But, 400 would be A-flat. With a constant A flat droning
in the background, . . .
Yes, large 400 Hz power systems can be QUITE irritating,
especially with harmonics added.
The whine from a huge 415 Hz UPS running a large computer
installation is totally deafening.
Jon
