400 Hz

[Jon Elson]

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