VPI 2nd Pivot for 3D

What damping does is to stabilize the arm....the exact result of adding the VPI second pivot.

Damping the cartridge (as it is the initial mechanical source of sonically intrusive resonances) is I think, what the OP is looking at.

Practically, there would have to be modifications to incorporate it onto a Prime.

From my perspective, using the 2nd pivot, while it may be a sonic advantage, takes away the objective of the unipivot design. The addition of a damping trough, as in the Townshend, adds damping at the most critical point without changing the main objective of a single mechanical point.

This, to me, is the challenge of the potential project.

Slaw-
  Nothing less then thrilled to hear from you. In reference to your reply about the clamps, in keeping this in stride with the OP's discussion (and posting etiquette) , have you (in regard to your VPI) noted any increased stability of arm by using the clamps. Of course, that would have to be in regard to use with a unipivot, if that's what your VPI has.

  I find it interesting that you prefer no clamps. If I bought a rather warped record today I would return it as I always did years ago (sometimes not buying the album after 3 tries cause the whole lot is bad). My innate feel is that the clamps could sharpen or affect the sound in some way, simply for it's bed rock foundation (& how that would interplay with cart/stylus) - then again, for better or worse dependent on TT setup I presume.

I have never used a clamp, so I know not what I say, and I have never heard a clamped record play. As others here I'm reading and not in tune with experience. I've read probably 2 reviews (at least 1) that swore clamping made better sound, specifically with the ring on the Prime with 3D arm (of course that is the link I have searched my history back a month for & can't find- then, it was just a review).

So, I hope others chime in on the clamp effect in relation to stability issues on the unipivot arm. I have no electronics background but a year of physics, & it's that which made me think clamping a record no matter if warped or flat will make a different foundation to which sound can be affected. Bring the warped ones back and I'm thinking clamp the flat ones to affect sound production which could be beneficial dependent on the TT setup. But does it make a flat record sound better, if so, then I would assume it has a stabilizing effect on the arm.

 I have nothing to experiment with, some of you do, I just brought the clamping issue up to see who has noticed any beneficial stabilizing affects it may have on the unipivot.

 @Slaw; the Rock 7 is on my list but I don't want to hijack this thread with Townshend questions. I don't see a way to direct message you on this forum, is there? I have a pressing question on it. If there is no messaging here I can start a new thread-
Robes

Dear @robes: A clamp  normally  reduces the resonances/vibrations/feedback existent between the TT platter-mat/LP surface with the stylus tip. and from this point of view always is a benefit to clamp the LP.

With clamp or with out it the unipivot tonearm stability will be there, you can't avoid it using any clamp type. The second pivot is not the total cure, it's only something to reduce the stability problems. Best is to look for pivot tonearm with fixed bearing design because the cartridge needs full proof stability: zero tolerance.

Unipivots are more easy to design but is not a tool to use for a cartridge ridding LP grooves.  Is a mistake to use it that goes against the quality level performance. I know that some audiophiles really likes it but ( even that they don't know. ) it does not means is rigth.

We have remember to " see " the stability subject at the microscopic level that is where the cartridge stylus tip has to " negociates " those " rude " LP grooves. Believe me that the cartridge tracking job is a really hard and huge task and not so simple as we can imagine it.

Regards and enjoy the MUSIC NOT DISTORTIONS,
R.