I suspect that the main reason the Grace F9 cartridges are spec'd for 100K (if indeed they are; more on that in a moment) is to extend their bandwidth to 45 kHz, for playback of the CD-4 quadraphonic recordings that were marketed in the 1970's.
Without detailed technical information, including the inductance of the cartridge, it's impossible to say for sure, but my guess is that with 47K loading their frequency response at 20 kHz would be rolled off to a degree that is imperceptible, if at all. And in fact some phono stages could very conceivably be happier, in terms of intermodulation distortion or other adverse effects, if less ultrasonic energy is sent into them.
I have the original brochure that came with the F9E I purchased in 1979, and it states "resistance (K): 30 to 100." I assume that refers to load resistance.
That said, I've always run mine at 100K, using the phono section of a vintage Mark Levinson ML-1 preamp. I haven't ever tried its 50K setting, which is selectable via internal DIP switches.
Regards,
-- Al
Without detailed technical information, including the inductance of the cartridge, it's impossible to say for sure, but my guess is that with 47K loading their frequency response at 20 kHz would be rolled off to a degree that is imperceptible, if at all. And in fact some phono stages could very conceivably be happier, in terms of intermodulation distortion or other adverse effects, if less ultrasonic energy is sent into them.
I have the original brochure that came with the F9E I purchased in 1979, and it states "resistance (K): 30 to 100." I assume that refers to load resistance.
That said, I've always run mine at 100K, using the phono section of a vintage Mark Levinson ML-1 preamp. I haven't ever tried its 50K setting, which is selectable via internal DIP switches.
Regards,
-- Al