Triplanar vs JMW 12.5 on TNT 6

Sirspeedy,

Are you sure you didn't mean effective length? The Triplanar has an effective mass of 11 grams and the VPI 12.5 an effective mass of 11.2 grams. Not much of a difference. The VPI 12.6 has an effective mass of 10.1 grams. Also, not that different from the Triplanar.

Now if you are talking effective length, the Triplanar is 250mm and the 12.5 and 12.6 are 315mm - a significant difference.

It is true that the diff. here is not great.Mass wise.Take a look at the Galibier website,he makes mention of the fact,in his opinion,that the longer lengths are not really much advantage.I'm not trying to create any contoversy.Both options are OK with me,but Galibier's site,and regarding the fabulously interesting Schroeder arm,has some prevelent points.Good luck!

A longer arm has less tracking distortion. However, a longer arm is more prone to vibrations and can be less rigid. Frank Schroeder feels the benefits of the longer armwand are outweighed by its drawbacks. Thus, for his arms, he suggests people stick to the standard 222mm arm wand.

The VPI arms are a different situation. The VPI arms are unipivots with a center of gravity far below the pivot point. This means that small changes in arm height make a large change in vertical tracking force (VTF). I have a 12.5 arm. One revolution of the VTA tower changes VTF by .03 grams. For some cartridges, that have only a small VTF range, switching from a 100gram LP to a 200gram LP can significantly change the VTF and the sound. For my Colibri cartridge, I have to change arm height everytime I change LP thickness. It is a pain. The VPI 10" arm, because of its shorter length, is even more susceptible to this problem.

This article gives a more in-depth view of the situation.

http://www.tnt-audio.com/sorgenti/vta_e.html