Some attribute greater dynamics to higher output cartridges, but I haven't been through enough cartridges to test that hypothesis.
I have, and those attributions are not consistent with my experience. Nor are they consistent with theory.
LOMC's have lower moving mass on the cantilever than HOMC's. That's why they make them. A lower mass accelerates more rapidly and to greater amplitudes than a higher mass. Faster accelerations and larger amplitudes generate faster rise times and greater voltage differentials. Newton's laws work very well here. The difficulty comes in trying to preserve and cleanly amplify such tiny voltages without distortion or noise.
IME the most dynamic cartridges are all LOMC's, other things being equal of course. Of course the Koetsu RS is not particularly low output, and it may be not that dynamic a cartridge (don't know, haven't heard it). Still, it's probable that inadequate gain is part of the problem. Impedance loading may also be involved.
David12,
Here's an easy test: do you listen to line level sources at significantly lower gain control settings? (My recollection of demoing the Premier 17 with a CDP was that gain was set in the 20's, not the 50's.) If so, adding more phono gain should certainly help.
I have 67db before my line stage. That is slightly more than optimal for a .5mv Shelter 901, but only slightly. 57db would be inadequate even though the 901 has a reputation for being a "robust" .5mv cartrdige. If, as you suspect, the Koetsu is acting like a polite cartridge that also has less than .6mv output, then 57db probably wouldn't be enough.
Changing phono stages to one with more gain would be one solution. I defer to others with more experience for recommendations.
A high quality stepup transformer would also help, and that is my preference vs. FET-based high gain stages. YMMV. I've heard 4 or 5 different stepups with various cartridges and have yet to hear one that regularly betters the BentAudio Mu. They are available wired for 14db, 20 or 26db of gain. The best choice would depend on the Clearaudio's gain on its 47K MM input, which is where a stepup normally should be plugged in.
If you do go with stepups, consider this VERY carefully: MC's playing into a transformer are EXTREMELY sensitive to impedance loading, far more than when playing directly into a gain stage. Impedance changes of .5 ohm or even less are not only audible but sometimes critical. A change that small wouldn't even be noticed playing into a gain stage. The BentAudio design allows for instant and flexible load resistor swapping. I have found this to be of immense value when fine-tuning cartridges. This ability to optimize cartridge performance is the reason I prefer a good stepup. It's more work but the results are worth it, to me anyway.
BTW, if maximum dynamics were your primary goal then a low compliance cartridge like a Koetsu wouldn't be an obvious choice. But you know that already.
