Antiskating .... The last analog secret

Skating force is the product of the stylus' friction in the groove times the (imaginary) lever arm, whose length is the distance between two parallel lines: one, the L/R center-line of the cartridge and the other, a line parallel to that one but drawn through the main vertical axis of the tonearm's rotational main bearing. This lever arm distance remains the same no matter where on the record the stylus is; and unless the stylus' friction in the groove varies from outside to inside grooves, the skating force remains constant (although it's higher on loud passages due to more groove friction ;-)

If your tonearm has no headshell offset, nor an 'S' curved armtube, then no skating force will develop and you don't need any antiskating force. This is OK for 12" and longer tonearms which don't have much tracking error anyway.

The easiest way to check anti-skate (without an oscilloscope ;-) is to just look at the cantilever dead on as you lower the tonearm to the record. If just as the stylus goes into the groove, the cantilever shifts to the outside (relative to the cartridge body) you need more AS. If it shifts to the inside, you have too much. Note: (a.) This takes a little practice and a lot of light. (b.) It's easier to do with high compliance (MM) cartridges than with low compliance (MC) cartridges because squishier suspensions (MM) make the cantilever shifting easier to see. However after a little practice, it IS possible w/ MC cartridges. And anyway, this is to get you in the ballpark; final adjustments (no matter what method you use) will have to be made by ear. (Tip: try doing your listening tests with a mono record.)

Although the visual (+listening) method described above is as good as any I've tried, anti-skate adjustments render very subtle results. So it's exremely important that all other parameters be on the nose; including perfect azimuth, which is especially important when trying to find the correct AS force.
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Nice to have you back with your wise advises Nsgarch !

Hey, Doug. It's me again. :)

I would definately agree that calibration with a blank surface is never precisely correct. However, I would presume it's a very easy way to set an initial anti-skate (assuming you have a tonearm that allows you to set anti-skate and you find it to be a sonically valuable offset).

If you haven't learned this about me yet, here's another clue - I like my processes and I like my lists. :) I would bet there a progressive set (each with greater acuracy) of approaches for setting anti-skate:

ASL 1 - Do not use anti-skate
ALS 2 - Use a proporotion of VTF as your anti-skate setting
ALS 3 - Use a blank portion of LP; increse AS until arm remains motionless
ASL 4 - ?
ASL 5 - Set anti-skate using oscilloscope
ASL 6 - Set anti-skate by ear

However, 2 questions come to mind:

1) Was the damage noted in the picture caused by too much AS, or not enough?
2) Which of the above listed Anti-Skate Levels is sufficient to prevent that type of damange?

Guys,

Suggest you go to 6moons.com/archives/audio reviews/analog sources and read the Vinyl Setup Guide: The Guru Papers. Interesting approach to setup and it addresses antiskating.

Great idea for a thread Thomas. However, I don't believe that damage was from AS. Looks too severe. Or were you suffering from the latest AS theories at the time? :-)

I learned from Paul and Doug that AS is at best a necessary evil. So I take the approach that only a small bit of the evil gets into my vinyl playback. I've learned to identify when that distortion is on the record or in the reproduction chain. The result is that AS is almost non-existent, but more than what they use. I think this goes along with what Nsgarch looks for. We may use a different method but the desire is the minimum amount of AS just the same.