In article ,
The Natural Philosopher wrote:

What top frequencies would those be then, on a 78rpm? typically 200-3khz
if that.

Depends. 78s were actually produced much later than many think. Pye even
making them out of vinyl. 10kHz plus isn't unknown. But something out of a
booth could be no better than telephone quality.

--
*Atheism is a non-prophet organization.

Dave Plowman London SW
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