Lehman Black cube setting with Grado Platinum

I have a Grado Platinum cartridge playing through a Lehman Black Cube pre amp using a Krell KRC2 & FPB300cx main.
I have it set as recommended in the manual at 47k. I believe it should sound better. Has anyone tried & is it OK to use some of the other MC settings? The output seems to be fairly low even though it is their standard output cartridge.
If someone has found the "optimun setting" for this combination please let me know. I will have some time this evening to give it a try. Oh, yeah. I believe the cube is the older version without the new power supply if you think this makes a difference.
I am currently using a Grado Reference cartridge (4.5 mV output) with a Lehmann Audio Black Cube SE (which was the original version before I did the SE upgrade). The cartridge loading I use is 47 kOhms, with a 40 db gain setting (the setting specified for moving magnet cartridges). Since the Grado cartridges are moving-iron designs, which are somewhat less affected by the loading than true moving magnet designs, I think you should experiment with different impedance settings and see if one of them is more pleasing to you.

Can you clarify your the following points?:
1. Why do you think the cartridge/phono preamp "should sound better"? What aspects of the sound are you dissatisfied with?
2. What turntable / tonearm combo are you using? It's my experience that the TT/tonearm combo is as important as the cartridge you are using, so this is an important part of the equation.

The rest of your system is certainly first-rate, so it strikes me that you may be feeling dissatisfied because the Grado Platinum cartridge / Lehmann Black Cube aren't in the same league as the rest of your components, which are quite revealing of deficiencies in the upstream components.

As a first step, I strongly suggest that you upgrade your Lehmann Audio Black Cube to the "SE" version. The "SE" version offers a noticeable performance improvement over the original version, and the upgrade is not expensive (about $275, as I recall). When I upgraded my Black Cube, I was very pleased with the improved sound quality: much better bass response, a more transparent mid-range and treble, and somewhat better soundstaging (which was already pretty good).

If you are still vaguely dissatisfied with the sound of your analog front end, then you should consider getting a better cartridge. The Absolute Sound lists a number of cartridges in the $500-750 range that are worthy of audition, but one caveat: if you decide to buy a moving coil cartridge, you may find that the Lehmann Black Cube will also need replacement. Several audio reviewers (such as Michael Fremer) have written that the Black Cube is more "simpatico" with moving magnet cartridges than with moving coil units. I have no personal experience with this, so I only pass the remark along for what it's worth.
Thanks alot for your input. I am using a Technics SL1210 turntable with the stock arm. Some people think these are "scratchers" turntables but I am happy with the unit. My last JVC with an SME tonearm took a dump a couple of years ago. I can barely tell the difference & I am not so sure that I really can. It is almost ( & I mean almost) totally quiet. I am not happy with belt drive turntables because of the maintenance of the belt, etc. Only at very high volume can I detect any motor noise between passages and that may be questionable. I tried a Shure V15vmxr cartridge and hated it. Sounded so flat I off loaded it. Then a Sumiko BPS and it was OK, but I like the Grado. With it I can detect sounds from the original recording tapes (hiss) and other small sounds. The only thing that really disturbs me is the volume must be turned up much more than with CD's & the FM tuner. I am going to try changing the dip switches from all off to having #1 on. This is supposed to bring up the gain according to the manual. Hopefully it doesn't bring up the noise either.
I was hoping to see if anyone else has tried the different settings and what they had experienced. I may try the Lehman upgrade as you sugjested. Oh yeah, the speakers are Infinity Rennaissance 90's.
Thanks alot!
Did you ever figure it out? I am having the same issue with an original black cube mated to a technics sl1500m2 with a grado gold. I have it set to the MM settings and its a descent sound, but you really have to crank the volume. I'm not use to that seems to loose some punch as well I think when ran that way. I haven't been into vinyl in years so it's sort of new to me. I didn't care about cartridges back in the day just good music.