VPI VTA Base question

Does anyone know how to tell the difference between VPI's current JMW VTA base, and the 12" Unipivot Base?  Something visual? Or measurements? 

I can't achieve the proper alignment with my 10" Fatboy arm and want to make sure I got the correct base.



If the VPI forum is still active, might be worth searching. Reaching out to VPI is in order too.

Are you using the VPI protractor? If so, it's supposed to be a distance that's somewhere between Stevenson/Baerwald. If you have an aftermarket jig, perhaps try Baerwald, which might push the cart more forward?

I've read random reports some cart brands for whatever reason just won't cooperate with any amount of fussing.

Thanks for the response's so far........

but back to my original question- can anyone tell the difference between the 2 arm bases? Something visual or something I can measure? Visually they look the same to me on VPI's website.

I recently acquired what's supposed to be the JMW VTA and I want to make sure I got the right one before too much time goes by.

I do have an email into VPI, but the site says may not hear back from them for 3 days.




If you are using a vta tower designed for the JMW 12 series tonearm on a table that typically uses a JMW 10 tonearm, and you use the original JMW 10 mounting holes for the JMW 12 vta tower, you will not be able to get the correct 300mm S2P distance without remounting the vta tower.


The VTA 12 has a larger dog leg platform than the VTA 10

I got confirmation from VPI that I do have the correct JMW VTA base. I'm just puzzled as to why I can't get the proper alignment when I have the correct P2S distance.

Right now I'm using the VPI jig and the diamond is at the forward most part of the circle, almost just off of it, with the cart as far back as it will go. I know it's close, but it's not right on, and leaves me no room for tweaking. I do plan on getting a Mint protractor soon and I'm sure there will be more adjusting to come.

The only solution I can come up with is to remount the base for a P2S distance of 260mm (2 mm over). At that point I should be able to pull the cart forward to achieve a good alignment. I have a piece of ebony on its way. 

I'm still open to other suggestions, if anyone has one. 




I see you replaced an “original” jmw 10” arm. If you are using the vpi jig for that arm it’s for a p2s of 250 mm and a true 10” arm. The fatboy 10” is actually 10.5”. Could that explain your situation?