Tonearms with no anti-skate adjustment

I am in recent possession of a Grace 704 uni-pivot tonearm, which has no anti-skate adjustment. This is not optimal IMO, but should I really be worried?

jdjohn02-27-2019 3:09am

Showing 6 responses by moonglum

moonglum Details Discussions Posts This discussion Message User 619 posts 02-28-2019 at 04:43pm Copy Comment URL Report Comment Edit Delete Lew, Pleased to oblige. Consider an old-fashioned set of weighing scales. - The pivot point is high - The CofG is below the pivot - the scales are stable, balanced Now if one of the pans is manually raised upwards then released, there will exist a restorative force. A downward force. So to summarise, raised stylus = extra downward force. Rasied stylus could be due to warp or change in VTA. Both apply. Have a good day.
moonglum Details Discussions Posts This discussion Message User 619 posts 02-28-2019 at 02:50pm Copy Comment URL Report Comment Edit Delete Cleeds, Stringreen has made no mistake. Unipivots are generally designed to be as stable as that configuration permits. This means that ”lowering the tail end” increases downforce not decreases it as you have suggested.
moonglum Details Discussions Posts This discussion Message User 619 posts 02-28-2019 at 03:48pm Copy Comment URL Report Comment Edit Delete All 3 of you are wrong. If the C of G is below the pivot point (stable) then there will be a restorative force at the stylus. Have a good day.
moonglum Details Discussions Posts This discussion Message User 619 posts 02-28-2019 at 06:41pm Copy Comment URL Report Comment Edit Delete Lew, While I do not deny what you’ve said, remove the other supporting point, zero VTF so that it is balanced and floating freely, then the tonearm becomes analogous to the scale i.e. a stable balanced tonearm will behave in the same way. Your beliefs are contrary to those who have measured the force at the elevated stylus point and compared with “horizontal” arm measurements for VTF. Have you performed such measurement to confirm your belief?
moonglum Details Discussions Posts This discussion Message User 619 posts 03-02-2019 at 10:34am Copy Comment URL Report Comment Edit Delete Dear HDM, Brilliant post! I didn’t even know this one existed! I know Werner from PFM and he is a very good guy. His knowledge of electronics, digital & analogue, is even more impressive. What is interesting about his measurements is that that the “underslung” COG examples all show the VTF increase, which is basically what we’ve been arguing about. Cheers!
moonglum Details Discussions Posts This discussion Message User 619 posts 03-02-2019 at 10:53am Copy Comment URL Report Comment Edit Delete Cleeds, It is not quite clear what you are saying here... You are the only person so far who claims to have measured it and obtained the result you describe. Was this a recent measurement i.e. did this phenomenon happen on your current system? If so, please supply details e.g. stylus gauge model, expected VTF, actual VTF, tonearm pivot displacement below normal (rough estimate is fine), tonearm/cartridge used etc. If you can’t clearly remember don’t worry, just guess. No stress. Kind regards,

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