I don't see why (and apparently neither does Mr. Yoshioka) with today's very powerful magnets that there's any advantage to making a lo-output MC cartridge (meaning anything less than .4 mV.)
When magnets were weaker and you needed more coil windings (than you do today) to produce output, settling for really lo-output in order to reduce coil weight and increase transient response made some sense. But even then, there were trade-offs. Hi-gain phono preamps and/or step-up transformers were needed to boost the weak signal; and both of those devices defeated the benefit of the lighter coil assembly's better transients, to some degree.
It didn't surprise me, therefore, that with the introduction of the Orpheus, Yoshioka-san has abandoned the very lo-output model. Why bother? With the coil literally immersed in a "bath" of magnetic flux provided by the ring magnet design, a coil that produces .4mV (actually .65 mV using the CBS standard) won't need as many windings as in times past!
To answer Tim's question, I don't recall reading any direct comparisons of the Temper V vs. W with all else being equal. I would guess any perceived difference would be due more to having to drive the phono preamp harder with the V in order to match the volume to the W ;-)
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