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I have an origin live vta adjuster which I find a major PIA to use. You have about a whole mm of surface area to grab onto which is basically flush with the top of the armboard. I don't have particularly stubby fingers so I could only imagine how much worse it could be to use. I wish I had the speed nut or riggle product if it was applicable.
I got the isokinetik VTA adjuster for the Rega RB300 tonearm and found out that the thread did not fit the RB300. While the original nut fits the the thread of the RB300 beautifully the VTA adjuster doesn't.
Thinking it's a matter of bad thread I sent it back to the dealer and we agreed that he will ship me the "Michell" one instaed.
guess what ? ...The "Michell" didn't fit either !
Is it a case of both having bad threads or does my 1990 Planar 3 have a different thread than the one nowadays VTA adjusters are designed for ?