Based on my reading of Peter Copelands book MANUAL OF ANALOGUE SOUND RESTORATION TECHNIQUES i would suggest a constant-amplitude section below roughly 300Hz and a constant-velocity section above that.


Lars Gaustad
Senior Preservation Advisor
Digital Library Development - FILM
National Library of Norway

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Fra: Association for Recorded Sound Discussion List [mailto:[log in to unmask]] På vegne av Paul Stamler
Sendt: 11. mars 2015 20:28
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Emne: [ARSCLIST] De-emphasis for acetate discs?

Hi folks:

What de-emphasis curve is a good choice for acetate discs? I have six 78 rpm sides by a gospel quartet here, recorded in 1946 at a local studio. 
The discs are Presto, but of course that's no guarantee that the disc cutter was also a Presto.

Anyway, I'm  wondering what a good curve would be as a starting point? NAB?