Hi Steve,

I don't know the answer to your question, but Aida Favia-Artsay's Caruso book would be a good place to get the numbers for several standard Victor speeds. And, 75.00 is the one that she says is the same for both line frequencies. From looking at her other examples, though, it's obvious that the conversion is non-linear.

Gary

____________________________

Gary Galo
Audio Engineer Emeritus
The Crane School of Music
SUNY at Potsdam, NY 13676

"Great art presupposes the alert mind of the educated listener."
Arnold Schoenberg

"A true artist doesn't want to be admired, he wants to be believed."
Igor Markevitch

"If you design an audio system based on the premise that nothing is audible,
on that system nothing will be audible."
G. Galo

-----Original Message-----
From: Association for Recorded Sound Discussion List [mailto:[log in to unmask]] On Behalf Of Steve Smolian
Sent: Sunday, January 20, 2019 4:55 PM
To: [log in to unmask]
Subject: [ARSCLIST] Playing speed

Is there a formula to covert a specified playing speed at 50 cycles to the
playing speed at 60 cycles? Example: 75 rpm at 50 cycles, what speed at 60
cycles?

 

Steve Smolian