Wally used to call his WallySkater "one of my best Trojan Horses" because many invitations he accepted to setup equipment owned by proud designers or audiophiles often resulted in the destruction of the owner's faith in the quality of their equipment.
The WallySkater is a ruthless detective of bearing quality and poor anti-skating mechanism design. Over the years, the WallySkater has been an essential tool for finding problems tonearm manufacturers and audiophiles didn't even know existed.
How good is your tonearm?
What’s wrong with using test track records to determine the anti-skating setting?
Skating is caused by two elements: Effective Moment Arm and friction. Effective Moment Arm is a geometric function having to do with the relationship of the tonearm to the record. The friction that causes skating force is found at the junction of stylus and groove walls. As friction increases, skating force increases which necessitates more anti-skating force to counter it.
The primary cause of friction (other than the vertical tracking force, of course) is the contour (musical content) within the groove. Loud musical passages have greater groove contour and therefore result in greater friction. Anti-skating test tracks are extremely high contour/amplitude tracks that are designed to cause the tonearm to mistrack – something which is easily heard. However, recording engineers don’t want our stylus to mistrack so they don’t push the groove amplitude too far (and we can thank them for this). So, if we are setting our anti-skating according to signal amplitude in the groove which is almost never present during music playback then we will be setting our anti-skating for this high amplitude (high friction) track and therefore will have our anti-skating set far too high for normal musical playback, causing excessive wear on the right channel groove and stylus.