|
Vinyl Asylum Welcome Licorice Pizza (LP) lovers! Setup guides and Vinyl FAQ. |
|
|
|
Vinyl Asylum Welcome Licorice Pizza (LP) lovers! Setup guides and Vinyl FAQ. |
|
In Reply to: The ear posted by Jolyon on May 14, 2007 at 14:20:26:
1. Very sensitive. Hard to put a figure on it as the degree of sensitivity is also dependent on the time scale of the change - you may not notice a 600 ppm change (one cent of pitch) over the duration of a record unless you have perfect pitch. You will notice it if it fluctuates over a time scale of a second or less.2. The motor itself, yes, see answer to next question. There are other problem which are greater than the motor, the worst is belt creep. One post recently measured belt creep at a figure very close to the 750 ppm level I derived from theory.
3. According to data presented at leapsecond.com the short term Allan deviation of 60 Hz mains is better than 100 ppm. This is about equal to a standard quartz oscillator circuit. I personally think better stability improves sound BUT I'm biased as I have spent a lot of time and money on these improvements.
4. Early cutting lathes ran at mains synchronous speed so see 3 above. Later ones used quartz controlled direct drive which gave improved speed stability.
It's possible to do even better - I have been talking to a local guy about getting some frequency test records cut, once we work out the details I am hoping to build a new PS for his Neumann lathe so I can get better than 1 ppm accuracy.
Is this a waste of time? I guess I'll only know after I've wasted it.
Mark Kelly
This post is made possible by the generous support of people like you and our sponsors:
Follow Ups
- Whose ear? - Mark Kelly 16:12:03 05/14/07 (1)
- Re: Whose ear? - Jolyon 14:40:30 05/16/07 (0)
Top of Page ]
[ Contact Us ]
[ Support/Wish List ]
[ Copyright © 2025, Audio Asylum, all rights reserved ]
