If the cartridge needs additional loading that should be placed at the
primary of the SUT to load the cartridge directly. I find secondary
loading to make a cartridge behave under various situations to be a
sonic band-aid.
Years ago I found it interesting that people who
use active gain stages tend to find their MC cartridges insensitive to
loading and those who use SUT's can get fanatical about it.
FWIW the loading doesn't do anything for the cartridge at audio frequencies except reduce its output. The loading is audible though, but that is because it detunes the RF resonance caused by the cartridge inductance and the tone arm cable capacitance.
If the preamp is insensitive to RFI the loading doesn't do anything. 47K is therefore an effective load. I've heard loading make a difference but when you get the RFI problems sorted at the phono input, that difference goes away.
While the Jensen is one of the best SUTs available, being best isn't the same as being right for all cartridges for the reasons Dave mentions above. Quality and application are two different things!
But in Stu's system, the problem he described sounded very much like any phono section that isn't getting enough signal. Dynamics wake up, the sound is more vivacious when that is rectified. So comparing the Jensen which is set up for a low boost to a transformer set up for a lot more may not be about the transformers so much as it is the amount of signal presented to the input of the phono section. For that you would have to have both set up as much as possible the same way.
