Skating Force - A Practical Demonstration
You learned about the primary driver of skating force in Skating & Anti-Skating and you also know we have been whining about the fact that too many people - including some tonearm manufacturers! - claim that offset angle is a primary cause of skating force. Some manufacturers even use this belief to make changes in their pivoted tonearm designs which they erroneously claim allows their product to avoid skating force. FACT: It doesn't matter whether the design involves a pivoted headshell, an ultra-long armwand, a thales circle pivoted linear tracker or whatever: if the arm is a pivoted arm, it WILL have skating force that must be dealt with to preserve the stylus and the grooves.
PRACTICAL DEMONSTRATION - OFFSET ANGLE AND SKATING FORCE
We figured that publishing the mathematics behind our assertion would leave most people out of the conversation so we devised a simple practical demonstration to prove offset angle has nothing directly to do with skating force - though there is an INDIRECT relationship we'll discuss later.
With a grooveless record on the platter and a perfectly aligned cartridge with a spherical tip profile, we set about our little demonstration. The fact that the stylus tip profile is spherical is VERY important and will be discussed later as it is related to the relatively minor and indirect role that offset angle plays in generating skating force.
Here is the first video:
Skating Study (Part 1 of 6) - Normal Offset Angle
For the second step, we twisted the cartridge in the shell so that the cantilever would be aiming directly at the pivot point (on the horizontal plane, of course). This approach completely eliminates the offset angle of the arm/cartridge unit. We re-checked tracking force to ensure it hadn't drifted and tried it again.