First, I think it's instructive to ask: What is it about lo output MCs that they should be "more resolving"? And the answer is going to be, of course, better transient response of the mechanical assembly (stylus, cantilever, and coil) due to the lower inertia of a lighter weight (fewer windings) coil, assuming the other two parts and the suspension remain the same.
Lately however, two significant attempts have been made to reduce the effective mass of the moving assembly:
1.) In the van den Hul Colibri and Condor by lightening up the other two parts (the stylus/cantilever) by eliminating the front pole piece and shortening the cantilever, while maintaining (in some models) the larger number of coil windings, providing the best of both worlds: less inertia (livelier response) without sacrificing output. And let's not forget the good ol' Decca which, in the inscrutable British approach to things mechanical, has more or less been doing just that for years.
2.) The Transfiguration Temper, and to a slightly lesser degree, the Lyra Titan, have somewhat reduced the cantilever length and greatly reduced the number of coil windings, but still maintained a high-ish output (.5mV or more, depending which test record is used). They accomplish this feat by immersing the lighter coil in a much higher magnetic flux than that found in more conventional motor designs (such as the van den Huls)
There is an ongoing debate as to whether the magnetic inertia (or magnetic lag) inherent in step up transformers, trumps the increased transient response gained by using a lighter (fewer windings) lower output coil cartridge in the first place.
I don't wish to engage in that debate. Instead I will say, that in my ever so humble opinion, things have now advanced to the point where accepting that traditional tradeoff is no longer necessary. Shorter cantilevers, lighter all-diamond one-piece stylus/cantilever assemblies, lightweight coils in stronger flux fields, and better suspensions materials, have all yielded cartridge designs that produce respectable output levels without sacrificing that last little bit of resolution. I just don't believe it is necessary anymore to buy a 0.2mV cartridge to hear the last little detail. And then of course, take a chance that you might lose it all by running it through a transformer.
Lately however, two significant attempts have been made to reduce the effective mass of the moving assembly:
1.) In the van den Hul Colibri and Condor by lightening up the other two parts (the stylus/cantilever) by eliminating the front pole piece and shortening the cantilever, while maintaining (in some models) the larger number of coil windings, providing the best of both worlds: less inertia (livelier response) without sacrificing output. And let's not forget the good ol' Decca which, in the inscrutable British approach to things mechanical, has more or less been doing just that for years.
2.) The Transfiguration Temper, and to a slightly lesser degree, the Lyra Titan, have somewhat reduced the cantilever length and greatly reduced the number of coil windings, but still maintained a high-ish output (.5mV or more, depending which test record is used). They accomplish this feat by immersing the lighter coil in a much higher magnetic flux than that found in more conventional motor designs (such as the van den Huls)
There is an ongoing debate as to whether the magnetic inertia (or magnetic lag) inherent in step up transformers, trumps the increased transient response gained by using a lighter (fewer windings) lower output coil cartridge in the first place.
I don't wish to engage in that debate. Instead I will say, that in my ever so humble opinion, things have now advanced to the point where accepting that traditional tradeoff is no longer necessary. Shorter cantilevers, lighter all-diamond one-piece stylus/cantilever assemblies, lightweight coils in stronger flux fields, and better suspensions materials, have all yielded cartridge designs that produce respectable output levels without sacrificing that last little bit of resolution. I just don't believe it is necessary anymore to buy a 0.2mV cartridge to hear the last little detail. And then of course, take a chance that you might lose it all by running it through a transformer.