MadFloyd,
The distortion/ringing like sound you hear can be the amp loading down your preamp/impedance interaction, try the lower impedance setting on Joule preamp. Another thing to try is a different set of speaker cables, sometimes you get weird oscillations from the amp/speaker/speaker cable interaction. Third and more likely cause is flutter echoes, bad acoustics in your room, very often the ceiling is to blame as much as the parallel side walls.
You simply may not notice it as much with the other preamp but it's still there.
As far as Lamm, I personally prefer the all tubed LL2.1D. I've heard both. My Lamm M1.2's were incredible with Lamm preamp.
I've tried a few more preamps, mcintosh c500 and Ayre KX-R. Ayre offered a bit more resolution, detail, focus but neither preamp could match the synergy and musicality of the Lamm on Lamm combo. They are meant to compliment each other. Expect rich, harmonically saturated and colorful tone, perhaps just a touch darker up top than SS preamp but utterly musical and enjoyable! I loved the LL2Deluxe I owned with the M1.2's.
Oh yeah, you'll be surprised at the bass texture/articulation, especially if you have a decent vinyl rig.