Unipivot tone arms

I have had two undamped VPI unipivots, a 9" on the Scoutmaster and a 10" on the Prime.  Yes, they are "fiddly" and need to be handled with care, but I like the simple technology and have never noticed any distortion or noise that I could attribute to the arm.  VPI has now moved to a gimbled arm(s) and may not make the the old unipivot any more.  I suppose there is a good reason for this change.

I agree with the sentiment that it is all in the execution. Each implementation has theoretical advantages in some way and if properly designed and executed, any of them can shine. A tonearm is a precision instrument so the best are not inexpensive, but I think once you reach a certain level they all are very capable performers.

I have Kuzma Airline linears that are superb, but I think my Bird of Prey (http://www.robyattaudio.com/) unipivot is a bit better. It is viscous and magnetically damped. It is in no way "wobbly." You would not know it is a unipivot just by how it feels. The designer claims that a unipivot can "lock" into the groove in a way that non unipivots can't.. Makes sense that it is more adaptable in that way. In any case, some of my lesser cartridges sound really, really good on this arm. The better ones sound superb.

I've also had extensive experience with the Moerch DP-8 and it is also world class, especially for the $$.

Like I said at the beginning of this thread, there are many modern tonearms that could be categorized as "unipivot", but the best ones are actually modified unipivots so as in one way or another to cure the inherent issues with a pure unipivot. Graham, Kuzma, VPI (with the add-on option), and I am sure many others are in this category. Results can be superb. But a pure unipivot, like the Keith Monks (which I also once owned) is passe’, in my opinion. Besides, the mercury bath contacts (Keith Monks) were a nightmare.

I had a cartridge trial back in the 1970s which definitely had a mismatch with the tonearm as it couldn’t track any warp.

Prior to using a gimbaled arm, my Brooks Berdan highly modified SME IV from 1989, I used unipivots. I still use an Ultracraft 400 unipivot arm on a VPI 19-4 with a Grado G+ 78 cartridge with no dampening (silicone in the base). It works great.

For my LPs, I use the SME above with a Dynavector 20X2 L (previously with a Benz Ruby 3). It is so great other than setting up it’s VTA (spring loaded and coarse adjustments).

My best friend has an upgraded VPI Scout with a unipivot VPI arm. We don’t notice any problem with the bass using a Dynavector 20X2 H. Tight and deep bass, tracks warps great.

This is a very interesting forum. If I were to purchase a "unipivot" arm in the future, I will ensure that it has some type of balancing/range mechanism rather than a totally free floating (like my Ultracraft) arm. The Tri-Planar arm was a second choice to the SME but more expensive at the time.

Unitrac parts.  Out of my own necessity for parts for this arm, I am making parts for this arm, specifically the anti-skate bucket and the headshells - likely more as demand follows.  If anyone needs these items please email me @ [email protected]