I often run my MC cartridges wide open (47K) if the phono stage permits. Otherwise choose any load R that is at least 10X the internal resistance of the cartridge. In this case 100ohms or any value greater would suffice. Use your ears. The negative effects that eventually set in as you reduce the phono stage load, as described by Miller carbon, occur when you reduce the load resistance below some value that usually is at least 10 times the value of the internal resistance. Also, when you go below that ratio, you begin to lose voltage output to ground, and the apparent gain of the cartridge is reduced, and the cartridge sounds muddy. Just don’t go down that far, and you won’t have that problem. Since vdH recommends 200 ohms or greater, what more do you need to know?
By the way, contrary to what miller carbon says, low output moving coil cartridges do make appreciable current. That is why the interest in current driven phono stages has legs. You can calculate for yourself the current output of an LOMC cartridge. Just divide its signal voltage output by its internal resistance. If you think about that equation, you can see that cartridges with very low internal resistance make more current, compared to higher voltage output cartridges that also have much higher internal resistance.
By the way, contrary to what miller carbon says, low output moving coil cartridges do make appreciable current. That is why the interest in current driven phono stages has legs. You can calculate for yourself the current output of an LOMC cartridge. Just divide its signal voltage output by its internal resistance. If you think about that equation, you can see that cartridges with very low internal resistance make more current, compared to higher voltage output cartridges that also have much higher internal resistance.