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Zero Antiskate vs Stylus Wear

This article, based on a long term study, was “plagiarised” from another Forum. It’s quite an old article so apologies to “older heads” for whom this may be old news.
It comes from an era when light VTF = good, but was not necessarily true, however the basic principle of long term wear looks sound.
Styli were tested to destruction over their full lifecycle.

http://www.audiomods.co.uk/papers/kogen_skatingforce.PDF

Viewers may have to cut & paste but in the event of difficulty with the link I will give a brief summary :

Of 14 cartridge samples tested without bias, 9 of them suffered excessive wear on the inner groove. One was neutral and the remaining 4 were “outer wall”.
When bias compensation was applied to a group of 6 samples, the wear pattern that resulted was symmetrical.

Given the strong and logical argument that skating damages styli asymmetrically – and gives a skewed reading of the LP over time, the “deviations” are a concern i.e. why 4 of them behaved oppositely.
Poor bearings? Arm cable too stiff? Wrong geometry?

IMO most turntable enthusiasts considered it self evident that unilateral force would cause this type of wear pattern so we didn’t need to be told but documented study, even one as old as this, is always interesting.
The photograph of the spherical stylus is poorly resolved on this copy but it makes the point quite graphically.

Based on long term experience that the simplest things can affect the sound of a turntable, I cannot deny that the idea of “de-stressing” the cantilever by removing a poorly directed/located AS force IS attractive and may produce a degree of audible benefit…at first...(?!?!?!!!)
The doubter in me always asks the question : can a mechanical assembly successfully zero out all mechanical influence and give a pure result? (If true zero AS is the goal even arm damping might be prohibited?)

The principle of using excessive VTF (up to 50% more) to achieve the same “trackability”, without bias, it was suggested, merely accelerates the unilateral wear & tear with (presumably) commensurate damage to the LP(?)
The proposed compensation of up to ”50% extra VTF” sounded a bit excessive to me.
(I’d balk at applying more than 0.1g over maximum.)

Old as it is, I found this study mildly unsettling.
Comments and opinions are invited from both Zero-antiskate adherents and those who always use AS.
moonglum
moonglum OP
619 posts
 
Dear Actus,
Many thanks for kick-starting the thread. I had indeed given up on it a while back :^)

Yes, the VPIs are among those odd cases where the cord is temptingly placed for manipulation.
I suppose to verify that there was no interference from it you would have to do the Balanced free-arm friction test to see if it slows or accelerates at that "twist" setting?
Not sure how easy that is to perform with a unipivot design such as the VPI.

Since you're happy with the sound and the tracking, there may be no need to question or test it. :^)
Best....
actusreus
733 posts
 
Moonglum,
You're welcome! And just to make it clear, I do not question whether skating forces are of concern or to be ignored. I'm certainly not going to argue against the laws of physics. I merely noted that certain designs, such as VPI, might be handling the issue in their own way, whatever it might be, a strategically positioned wire or twisted wire. If that is the case, the tests are of limited value if done with different designs. I'd still very much like to examine my stylus at some point to determine any wear due to the skating forces, but right now I'm just going to enjoy the music!
rauliruegas
13,125 posts
 
Dear Moonglum: There is no doubt that we have to take in deep care on the right TT/tonearm/cartridge set up mainly recovery all the grooves recorded information and to degraded the audio signal the less.

Sometimes we fail on that " perfect " set up and if not we the analog medium is in charge to, due to its multiple imperfections, make it fails.

We can have a perfect set up but the off center LP has to much to " say " and the non-flat LPs full of waves makes that our " perfect " set up goes down changing all the time the VTF/VTA/overhang during playback and we can't do almost nothing to stop it.

There are so many set up parameters that always affect the cartridge traking/ride that in some way we are at " random " for what the analog medium " decide " it self.

The analog medium in theory could be exact like mathematics but on playback we experienced many times that that analog set up parameters theory is not acomplished. Imperfection is the name of the game.

Anyway, I always try to be as accurate as the medium permit me.

Regards and enjoy the music,
R.
tonywinsc
583 posts
 
Raul, your point is well taken. That is what makes vinyl playback so interesting. Perfection gets boring after a while. Something so special or romantic about the glow of the preamp tubes, the spinning platter and those golden tones- with a little background crackle :)
moonglum OP
619 posts
 
Dear Raul,
I cannot agree more.
Like you say, perfection can only ever be a theoretical one. Adjusting factors e.g. on a per record basis would be soul destroying because one factor offsets others – which in turn would require correction. Such levels of technicality would quench the spirit and defeat the very purpose of listening to music.
It’s eminently more sensible to spend many days and many records advancing the setup to a happy medium then simply enjoying it. Perfectionism is only useful insofar as achieving the working ideal for one’s own turntable/s whilst in full realisation that temperature, humidity, record warps, manufacturing errors, stylus cleanliness, record cleanliness, etc are the Devil’s way of making sure it doesn’t always run smoothly.

It’s true, we can change our ambient temp or VTA or VTF seasonally to compensate for Summer-Winter changes, depending on which is easier, and we may clean our styli at different intervals, and if we have easy VTA adjustable arms we can alter the level of the arm from 120g -180g as easily as throwing a switch - thereby keeping that idealised relationship unaltered but when it comes right down to it, it’s all about maintaining a reasonable equilibrium.

Regarding your comments about record warps, I do find it interesting that if we introduce a 120g to 180g VTA offset we can clearly hear it and quantify it, yet our ears can be extraordinarily forgiving when it comes to warped LPs (which affects all LPs to at least some degree). Perhaps the ear/brain interface actually compares average rather than instantaneous values? :^)

Speaking of mis-drilling : one of the most obvious examples of wrongly produced vinyl is the HFN/RR test disc. I’ve owned a couple of samples of this and the centre was always drilled 1 or 2mm off centre.
This would result in a wavering effect when using it to adjust bias, with associated intermittent cyclic mistracking on the more severe tracks.
(Personally, I only use music to adjust bias but if one must use an HFN/RR I would advise only to focus on the fadeout of the 12db tone. With some carts of varied trackability and in various states of wear, I’ve heard the tone pulling to one side as the signal level falls to zero instead of remaining centred…although don’t be surprised if your cart shows no difference at your ”ideal” setting.)
Best regards…
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