Well,,the rule of thumb is 10-20 times the internal impedance. Not sure about the Ruby II, but for my Benz LP the internal impedance is 38, so the range would ideally be 380 to 760. I starded out with 47 k on my Pass Xonon, and that was way too bright. Currently trying 1000, which is a lot better but perhpas still too high. The cartdige and tonearm cable are still breing in, so I will wait a bit before I try to go lower...There was a recent review in a UK magazine by Scott Markwell (sp) who alos writes for TAS. He personally liked the LP at 47 k, and I know that AJ Conti prefer this setting with the LP as well (private email). In the end its up to you - in general , a higher setting will emphasize the top end if you go to low the bass will get slushy. You may want to post the question on Audioasylum and/or search their archives...