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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
dertonarm
1,042 posts
 
In general - "skating force" is not linear. It is general with modern styli much less than it used to be in the 1970ies. Several respected tonearm designers (Pierre Lurne, Mortensen, ...) do recommend not using anti-skating at all and for good reason - applying a steady and linear "anti-force" upon a non-linear force is not a good idea at all......

Dampening - if you REALLY need it, the cartridge/tonearm match is less than optimal in terms of its mechanical parameters.
In general - less is more with both issues.
If you apply any dampening fluid, do use as little as possible and do use fluid which is NOT like honey but more like water......
If you apply antiskating at all, do set it as little force as possible - 1/2 of what is recommended by the manual will be enough and more than that.
The higher the VTF - the lower the antiskating !
headsnappin's avatar
headsnappin
295 posts
 
Great posts that are spot on!
dougdeacon
3,338 posts
 
Agree with all the above.

With regard to your question, on most unipivots that offer fluid damping in the bearing well, the fluid must actually touch the upper (movable) portion of the bearing to have much audible effect. Just damping the well isn't going to do much. I haven't played with the damping on a JMW, but if your well is tall enough to allow it, that's the right idea.

That said, I'd heed Nsgarch's sage analysis regarding damping with this particular cartridge/arm combo. Your bass and dynamics response are borderline now. Even a little damping might impair them noticeably.

Of course you could try it and hear for yourself. Just remember, once you've added enough fluid to touch the upper (free) part of the bearing, adjust in TINY amounts. Dertonarm's suggestion to use thinner fluid than what's considered normal makes excellent sense (again, because of your arm/cart combo).
srwooten's avatar
srwooten
694 posts
 
When you lift your arm off the well you should see a string of oil coming off the tonearm base. That is if you want damping. I would suggest using the damping oil that came with your Scout. Again if you want damping. Use a syringe to suck out any extra.

Anti-skate is arm/cart dependent- try it with your set up to see what is best. With my VPI 9 arm twisting the wire was perfect, with the VPI 9 Mem arm it is not.
tfkaudio
591 posts
 
Hi,
The lemo connector has a small amount of anti-skate bias, even when not twisted. Twisting it (counter-clockwise, I think?) will increase the anti-skate force.
I experimented with the anti-skate on this arm, both via the lemo connector and the anti-skate assembly. The difference I heard was minimal. I only heard a noticeable difference when way too much anti-skate was applied. The soundstage moved off-center and the sound became smeared.
I currently use the optional anti-skate with no weights on it. It makes no difference that I've ever been able to hear consistently, but it tracks the test record better and so I would assume it's probably better in terms of groove wear.
The great improvements I've made with this arm were the result of a) dialing in VTF/VTA, and b) nailing the alignment with a Mint LP protractor.
I've never tried using the damping fluid. Just seems too messy.
Regarding Srwooten's post, if you don't have a syringe handy, a Q-tip works too.
Cheers.

Tom
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