Does removing anti-skating really improve sound?

The Ledermann (of SoudSmith) video's mentioned above have a pretty good discussion of skating and how to do the adjustment.  The bottom line is that ANY method employed, and ANY mechanism will, at best, provide only roughly correct compensation, and that compensation will be, at times, too little and at other times too much.  BUT, absent some compensation, you will be subjecting records and the stylus to more uneven wear than is the case if you apply approximately correct compensation.   

This issue has been raised with a number of cartridge manufacturers and I don't know of any who endorse not using anti-skating.  

At best, any compensation is just a rough average of the force that is required to compensate for skating forces, the actual skating force varies greatly due to different operating conditions.  In particular, there is more skating force when the stylus is tracking highly modulated grooves (loud passages).  Some people set anti-skating by playing test records with higher and higher levels of play and then use anti-skating to compensate for distortion appearing in one channel (if the right becomes distorted, increase anti-skating).  The problem with this approach is that it applies too much compensation for more typical playing conditions.

Even though playing a blank groove does not reproduce actual playing conditions, it is used as a rough proxy for methods where you set anti-skating to cause a very slow drift toward the spindle when playing a record near the end of the record.  This method has been endorsed by a number of stylus/cartridge manufacturers who know a thing or two about wear on the stylus.  I like this method because it is easy.  You don't even need a blank record.  Put the needle down in the run-out section of a playing record and watch which way it drifts before it catches the groove.  You can look up Peter Lederman's (Sound Smith) videos on the subject.

As to the persistent issue of what causes the skating force, it is caused by friction of the stylus playing the groove.  The direction of that force pulling on the cantilever is roughly 90 degrees from the line between the two sides of the stylus contacting the groove.  For the most part, that means that the force is pulling along the same direction as the cantilever itself.  If the arm were straight, with no offset angle, the pull will be against the arm pivot.  But, when the cartridge is set at an offset angle, the direction of pull is no longer toward the pivot.  I have a simple way to demonstrate this phenomenon.  Place your elbow on a table and hold your arm straight out and then pull your middle finger straight back.  Your arm will not move because there is no sideways force.  Now cock your wrist toward the right, like the offset angle of a tonearm.  If you pull straight back on the middle finger like before, your arm will swing to the right.  This is precisely what happens with your tonearm.

S-shaped arms are no different from other arms when it comes to skating force because the cantilever on the cartridge is not pointing at the pivot.  That shape was chosen to balance the weight of the arm at the pivot.   

Yes, I would expect that lower friction would also mean lower skating force.  In any event, if it sounds better to you to not use the antiskating mechanism, you then only have to decide whether or not you are concerned with uneven groove and stylus wear.   Records are quite robust, so the issue of record wear might be more academic than a serious concern.  For me, it is enough of an issue that I use anti-skating.  In applying the Peter Lederman approach, with most arms, I end up using less anti-skating than applying the manufacturer's recommendations which are based on down-force setting.

mijostyn,

There is a good reason for not setting anti-skating to work best for the loudest passage.  According to a number of experts, including Peter Lederman of SoundSmith, skating force varies with groove modulation, with more force at higher modulation levels.  I don't know why this would be the case, but, that is what he claims.  If you set anti-skating to be optimal for the most extreme passages, it would be too high for the vast majority of time the record plays well below that level.  Because I don't need high anti-skating to reduce distortion when playing regular records (only test records distort grossly), I go with slightly less than what is indicated by playing test records at the highest modulation level.  Lederman's observations and recommendations are base on seeing observing wear on cartridges (he is a cartridge manufacturer and rebuilder). 

I know there are all sorts of methodologies, and all of them are, at best, rough corrections, so I don't sweat it that much.

A very rough experiment could be done with a blank record.  One could set anti-skating so that the arm stays roughly in place at a certain radius for 33.33 rpm, and then set the stylus down at the same point when playing a 45 rpm record.  If the stylus now moves decisively inward at 45 rpm, friction has increased with the increased velocity.

The coefficient of friction between sliding surfaces is not determined by a simple Newtonian physics equation.  At different velocities the value changes--it generally increases with increased velocity.  The shape, elastic properties of the surfaces, "slip-stick" properties, and a host of variables affect how much the friction will change with velocity, but the overall result is an increase in friction with an increase of velocity.  See for example:

http://www.physics.usyd.edu.au/~cross/PUBLICATIONS/30.%20FrictionvsSpeed.pdf

One can expect skating force to increase when playing a 45 rpm record vs. a 33.33 rpm record, even when both are playing an unmodulated groove.  The only way it would not increase is if "slip-stick" decreases so substantially with increased velocity that it overcomes all other tendencies for drag to increase.