loading question

Don't know about that particular cartridge, but most MC carts are not that sensitive to capacitance loading. However, the impedance load you've selected is far lower than usual for that cartridge, and I would wonder why it is sounding best at that low setting.

I own the Glider M2 with the .8mv output, and while I don't know if the internal resistance is actually the same as your Ruby H, I found anything below about 200 ohms to choke off the sound (I settled at just below 400 ohms, but that is highly dependent and subjective). I wouldn't be surprised if you preferred another setting, had you choices in the few-to-several-hundred ohms range, so you might want to look into the possibility of resistor substitutions. As far as the capacitance goes, first make sure that the control even has an effect when set up for MC and not MM carts, but if it does and you can't hear a difference between the options, I would leave it set at 100pf and forget about it.

Thanks for your imput. It really didnt seem to make a difference on the sound no matter where I set the capacitor value at thats why I wondering. David

With my MC cartridge with BC phono stage, it's the same story. It's the gain that makes the difference. With a higher outpout cart (esp. MM), I think those other settings would likely be noticeably different.