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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
quiddity
119 posts
 
Axelwahl

You said no groove = no offset. That's not correct.

The tangent to the arc of the stylus traces on the vinyl does not pass through the tonearm pivot. Therefore there is a separate vector pasing through the same point (the stylus contact point) which does pass though the tonearm pivot. The first vector is the stylus frictional reaction force vector, the second is the tonearm restraining force vector.

The angle between these two vectors is the angle I described as the "true offset" and which we are now going to call something else, hopefully slightly less cumbersome than "the angle between the stylus frictional reaction force vector and the tonearm restraining force vector". As explained above, the fact that the stylus frictional reaction force vector doesn't pass through the pivot is what causes skating. That's all there is. Nothing more, nothing less.

Mark Kelly
quiddity
119 posts
 
Axel

I've just read your post more carefully and my first response was too hasty.

I'm not familiar with the term "tangent trace angle" but by your description it is what I described as "true offset angle".

Indeed we may have been suffereing from terminological incommensurability.

Mark Kelly
perrew
299 posts
 
Mark, regarding Hertz are you saying the contact area of the vinyl is expanding due to deformation with increasing force, (I dont see the stylus deforming), and therefore the contact area might expand more than the force and P becomes smaller even though F increases?
axelwahl
788 posts
 
Dertonarm,
I'm a bit lost with the concept "that the bearing of the tonearm is not able to *completely support* the resulting force towards the inner groove"

All that means to me the friction of the tonearm-bearing subtracts itself from the skate force as it is an opposed force?

If you tighten up the bearing that much so is equals the skate force, the arm will not be moved by the skate force anymore.

Where it fits into the understanding of it all I'm not sure right now.

The friction force will create a vector forces due to the arm held at the pivot and produce a resultant force - the skate force. Actually pretty simple, until you want to actually calculate what this resultant force would be.

All we know, it's pretty much proportional to the actual friction force --- that force which we usually don't know and keep guessing about.

Axel
quiddity
119 posts
 
Perrew

No that's not what I'm saying.

I said I wan't going to try to explain Hertzian contact theory to you and I'm sticking to that.

Mark Kelly
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