TT speed

I have to credit Dover with causing me to re-think my prior position.  He simply mentioned that the cutting lathe is linear and the tonearm is pivoted (assuming a pivoted tonearm).  Rather than quantify the error, my simplistic approach is to start with the premise that the accuracy of the pitch (1000Hz) on this perfect LP being played on a perfectly speed stable TT depends upon the stylus remaining at a fixed point on the radius of the LP.  That, of course, doesn't happen with a pivoted tonearm; it touches the radius only at each of the two null points, assuming proper alignment.  When the stylus tip is off the radius, that represents relative movement of the stylus tip with respect to the recorded signal, which movement must change the pitch. Good thinking, Holmz.  Interesting discussion, too.

I’ve done a 180, reversal of my prior opinion.

Real or imaginary part?

I have to credit Dover with causing me to re-think my prior position.

Thanks @lewm It looks like we can credit @larryi , @dover  and others for helping me explain it properly. Many thanks fellows.

At first I was “… like… WTF.”
But then the math resulted in, “<and>… like… who cares…”

It is prolly just of minor intellectual curiosity, but does put “another one” in the clip of the digital crowd’s ammo against analogue. 😋 

@holmz

but does put “another one” in the clip of the digital crowd’s ammo against analogue.

I have a friend who designs DAC’s way beyond what is available publicly.

His description of red book digital is "it is only a little bit out ALL of the time".

Without going into the weeds truncation errors due to the sine x/x calculation are built into the red book standards. Digital data transfer also contains errors in transmission - it is possible to fix these as each packet has a check digit, but you would need a Fugaku supercomputer to calculate the corrections in real time.