550 to 800 is pretty much optimal with the Ruby cartridges. Any more than that and they brighten up and sound hard. My Benz LP prefers 100 ohm. To load these at 47k is misguided, in my opinion.
Loading for Benz Micro Ruby 2 Low Output Cartridge
I am using a Benz Micro Ruby 2 Low Output MC Cartridge with a WellTempered Classic TT and a Hovland HP100 Preamp MC Phono Section. The Hovland is set up for 550 Ohms load and the cartridge specifies 500 to 47K ohms requirement. Does anyone have experience using a different load?