The Natural Philosopher wrote:

Muy bad. 57Khz is the storecast ********. Was ultra low bandwidth muzak,
now RDS/

Anyway, sum and difference ws pretty much hat any Viny;l receord diod as
well.

Hic? Been at the whisky?

IIRC stereo on Vinyl is done by the two axes that the needle gets pushed
in - both 45 degrees from vertical. And it's very hard to move in one
axis and not the other, which limits separation.

If 'true' stereo is two utterly independent channels, you needed a tape
recorder or a CD, latterly.

Or many other digital technologies. I think it's actually a waste of
bandwidth; that hiss on FM is way lower on digital systems, so sum and
difference, or something more sophisticated is the way to go.

Mind, if you have the bandwidth and not the CPU power (which was the
case when CD was designed) send them both in full.

Andy