Re: [ARSCLIST] Mostly for laughs

[Mwcpc6@xxxxxxx]

In a message dated 10/23/2006 7:11:22 PM Eastern Daylight Time, 
insuranceman@xxxxxxxxxx writes:
I still don't know why the skating force makes the stylus pull IN.  If 
it were some kind of centrifugal force, it'd be thrown outward (or at 
least my very limited brain tells me that).  That's why I have four 
linear tracking arms--all various Rube Goldberg type contraptions.
Phillip
*******************

If you actually look at your turntable, you will notice that the tone arm is 
longer than the distance between the spindle and its pivot point.  

You should also notice that the far side of the record from the tone arm is 
moving in a direction that will pull the tone arm toward the spindle.

Most of the time, depending on the exact geometry of the turntable setup, the 
stylus is on the side of the turntable that is dragging it toward the spindle.

This is what causes the skating force that is minimized by the odd and 
sometimes complex shapes and taken by tone arms to minimize tracking error. A radial 
tone arm and a recording lathe do not have tracking error or skating force. 
It can be adjusted to be inward or outward during parts of the record, but 
can't be eliminated with a pivoted tone arm.

All of this talk about centrifugal force gets rather tiresome after a while. 
1950s Hi-fi magazines had endless articles about setting up tone arms and tone 
arm geometry to minimize tracking error and skating force. Tracking error can 
produce a small amount of distortion but skating force just produces a small 
DC offset to the position of the stylus and, unless extreme, in a poorly 
designed cartridge, has no effect at all.

Mike Csontos



Mike Csontos