VPI 2nd Pivot for 3D

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.

With respect to the question concerning clamping, I have a Stillpoints LP1, which I use interchangeably on both my VPI Prime and on my SL1200GAE. It makes a difference sometimes, but not on every record.  Generally records that are flat and 180 gram or heavier seem less affected by it.  I also have a Periphery Ring for the VPI and it definitely makes a difference on any record that is warped.  So much so that the Prime is my go to TT for warped records, regardless of any other consideration.  At the same time, for records that are not warped I hear no difference is sound with or without the use of the Periphery Ring.  In the interests of complete disclosure, my Prime is controlled by Phoenix Engineering Roadrunner/Eagle so speed accuracy and stability are pretty much the same with the ring or without.

With respect to the effect that the 2nd pivot has on the VPI arm it is extremely easy to back the 2nd pivot off and away from the pressure plate once set up to hear and see the difference.  It is doubtful that anyone who does this will decide after experimentation that the 2nd pivot does not provide a positive benefit.

With respect to Raul's arguments concerning unipivot tonearms, they are not clear to me, again I find it difficult to understand him, this is a language barrier problem for me, so perhaps I am misunderstanding?  Anyway, he seems to be arguing that there is some inherent "problem" with unipivots in the area of stability at the cartridge-stylus interface with the record groove.  He states this as a fact, but offers no data.  I would like to know what exactly the "problem" is with the data to back it up.  I am skeptical that there is any real problem.

Dear @billstevenson : I know that you did not read all my posts here and you don't have to do it but in one of them I posted this link and you can see what happens with any unipivot tonearms ( in this case VPI. ) about that unstability true problem that does not happens with pivot fixed bearing designs. Data?, here is a fact:
https://www.youtube.com/watch?v=iTTLM9gPU9o


Regards and enjoy the MUSIC NOT DISTORTIONS,
R.

robes,

I saw where you posted on the Townshend thread, so I'll join you there.