DaveyF, pivot "chatter" is an illusion created by people who are trying to make excuses for unipivot arms. Bearings in proper adjustment are preloaded. There is no clearance at all and no room for "chatter"
The Well Tempered arm is an interesting design, clever to a degree but like the unipivot basically flawed. A proper pivoted arm has two degrees of freedom vertical and horizontal. A unipivot has 3 degrees as it is free in torsion. The Well Tempered arm has 4 degrees as it adds torsion and longitudinal motion. Each free degree has a resonance associated with it.
The Well Tempered arm tries to deal with this by adding mass and fluid damping. These are crutches for flawed design. A properly matched cartridge tonearm pair should never require damping or added mass which adds inertia. It takes energy to move a tonearm through damping. It is like adding more friction and energy to overcome inertia. This energy comes from the record groove and can be seen on an oscilloscope as unnecessary cantilever motion. The cantilever moves because the tonearm does not, producing low frequency garbage, distorting the frequencies above. In really bad set ups you can hear it as a warble.
@tooblue, karl_desch is moving from a unipivot to a two axis arm with a Lyra cartridge. Follow what he has to say about it. it.
https://forum.audiogon.com/discussions/kuzma-4points-and-lyra-carts
