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Anti skate and tonearm damping query

I have read a number of threads relating to both antiskating and tonearm damping on the JMW 9" Sig.arm and find myself a bit confused.......I have been experimenting a little and have reached the conclusion that I must be deaf. I have not used the additional antiskating system, I have tried twisting and not twisting the leno wire and can hear no difference. If the Leno wire is not twisted therefore no antiskate, will this damage the stylus or the album??
I have also filled the damping well above the taper to the base of the point and still cannot hear 'the music being sucked out' or indeed, an improvement. Do I fill the well up to the point!! and then work backwards. Those that finetune using the damping seem to have some sort of epiphany when the 'sweet' spot is reached.

Can someone please shed light on how I should be going about setting the AS and finetuning the damping on the arm. The table is a scoutmaster with super platter and sds, the cartridge is the dynavector Te Kaitora Rua

Thanks
wes4390
stringreen's avatar
stringreen
6,472 posts
 
Dougdeacon...you're correct, but anti-skate decreases with velocity so that it becomes less and for all practical purposes, pretty much zero at the end of the LP. That being said, Highly modulated sections of the groove will create more skate than quiet sections all through the record. ...just clarification...I'm sure you know that.
quiddity
119 posts
 
Stringreen

That is not correct, stylus friction follows the classic Amonton law so the friction is independent of velocity. This can be confirmed by a modification of the test Doug Deacon used to demonstrate that Dertonarm's idea was completely false.

Using your blank disc and having satisfied yourself that skating has nothing to do with null points, set the antiskate on the arm so that the arm remains stationary at 33 RPM. Now change the speed to 45 RPM and observe the result.

Axelwahl antiskate is properly a function of offset not overhang.

Mark Kelly
axelwahl
788 posts
 
Dear Mark,
use your test, whereby the tip of the stylus only touches the vinyl.
The contact area thereby sees no off-set, and simply assumes the shortest point between contact area and pivot = one of the vectors. Overhang to the spindle is creating another sector, with the spindle to pivot a third.

Thereby off-set is not involved, yes?

Axel
axelwahl
788 posts
 
another *sector* should of course read: another *vector*...
dougdeacon
3,338 posts
 
Axel,

Try your experiment using a pivoting arm having zero offset angle (like a transcription arm). Provided the cantilever is aimed correctly (i.e., directly at the pivot point of the tonearm), skating force will be zero. This will be true regardless of overhang.

Skating force is generated when we mount a cartridge at an angle in the headshell such that the cantilever is NOT aimed at the tonearm pivot (in a word, offset). Overhang has nothing to do with it.

Using that transcription tonearm (which has zero offset by design) you could still create an inward skating force by mounting a cartridge at an inward angle, just as on a regular tonearm that has built in offset. You could even create an OUTWARD skating force by mounting the cartridge at an outward angle. Again, you could do either of these regardless of overhang.
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