[Scott Dorsey]

drichard wrote:
Impedance match??? Between the vinyl disc and the platter? Please
explain.

He's talking about mechanical impedance. If there is a vibration in the
record, you want it to be transferred into the platter and absorbed, rather
than be reflected back into the record causing a high frequency resonance
issue.

In fact, there's no reason you can't arrange a proper platter and mat on
a Neumann lathe, but you don't want something so compliant when you're
cutting records so you'd need to swap it and just use it for playback.
Note the Neumann is also intended to throw a lot of torque into the record
so there isn't a flutter issue as the cutting stylus drag changes. That's
a non-issue for playback since the stylus drag is a lot lower.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."