looking at upgrading my tonearm from a triplanar

Tom,

Durand Talea would be a significant upgrade. The Beta version of the Talea easily bested both my fully tweaked TP and Dan_Ed's in direct A/B comparisons, in my system and his, using UNIverse I and XV-1S. The production models now available include improvements based on Beta tester feedback and further research by Joel. I assume they're even better than what I heard. I'd have replaced my TriPlanar with a Talea long ago if I had the funds and time. Well worth your consideration.

FYI, the Talea also bested a Kuzma Airline in that owner's system, using XV-1S and Tranfiguration Orpheus. While the Airline had a few advantages, the Talea had a notably lower sound floor... clearer and with more low level detail... a more realistic presentation of acoustic instruments. This was agreed by five listeners, including the Airline's owner. If the Airline is sonically superior to the 4 Point (assumption based on price)... draw your own conclusion.
;-)

IME, a Schroeder Reference is not an upgrade to a properly set up TriPlanar VII or above. It may be better with some cartridges, but with a ZYX UNIverse (I or II) it would be a lateral move at best. In a direct A/B, with Frank Schroeder setting up his arm and me setting up the TP, the TP more than held its own. This occured before I discovered or implemented any of the tweaks detailed on the "TriPlanar Tips" thread. Many of those enhance the TP's performance in precisely the areas where the Schroeder should have an advantage (low sound floor). If using a high end ZYX, a fully tweaked TP will probably outplay a Reference.

Haven't heard a Phantom except briefly at shows, so can't say how that would compare.

The bearing ideally should not have to transfer any mechanical energy. If it does, this means that the arm and cartridge are mismatched (effective mass is incorrect).

Strongly disagree. The effective mass/compliance relationship tells us only how a cartridge/arm behave when considered as a spring-loaded system. It tells us nothing about how they respond to internal vibrations.

No cartridge is 100% efficient as a transducer. All cartridges respond to cantilever movements by:
1) converting some of this mechanical energy to electrical signal;
2) converting some of this mechanical energy to heat; and
3) not converting some of this mechanical energy at all, which remains in its original state as physical vibrations.

The mix of 1, 2 and 3 is unique to each cartridge and varies according to frequency across the entire audible band (and beyond). The portion that remains as mechanical vibration may propagate through the cartridge body, into the headshell, into the tonearm and beyond.

Depending on frequency and phase, some of these vibrations will be reflected by material boundary layers, potentially setting up internal resonances. (This is very audible with certain cartridges, like those ZYX models with a blue ball on the front.)

Other vibrations may be dissipated as heat as they travel through various materials in the cartridge body, headshell or tonearm. (Well engineered wood tonearm wands are especially good at this.)

Still other vibrations may travel the length of the arm and reach the bearings. At this point, Bpd24's question comes into effect... how will the bearings respond to this?

Some bearings (Schroeder, Well Tempered) are designed to absorb/dissipate such energies. They do so to a greater or lesser degree, but inevitably suffer some loss in precision and dynamics. Other bearings (Triplanar, SME, other fixed bearings) may pass some energies into the arm base, while reflecting others.

No single bearing parameter (including hardness) is sufficient to predict the behavior of this highly complex process, which occurs across a nearly infinite number of frequencies. In particular, the compliance/effective mass relationship has no relevance in this area.

Tom,

Thanks for your report and glad you're enjoying! Your finding echoes my experience and that of nearly all who've compared these two arms.

At these levels, I believe the differences of tonearms is not better/best, but just different. Boston's Symphony Hall is different than NY's Carnegie Hall, but is any one better?

At any level, I believe the near-unanimous reports of multiple owners deserve more credence than the beliefs of someone who, so far as I'm aware, has heard neither. In any event, equating tonearms to concert halls is too fantastic to merit discussion. By comparison, Homeland Security's interest in TriPlanar's bearing usage approached being meaningful.