I think your weak link in that set up is the amp. The preamp and phono preamp are good. I had a pair of Audio Physic Virgo's driven by a BAT VK-60 tube amp. Awesome setup. The LS7 and Bat amp are both balanced so that should help some. IMO the other posts are great choices, but your preamp isn't the weak point...
A Audio Reseach amp is a good match as well. VT100 or 50...BAT has a little different (and to me) better sound.
A Audio Reseach amp is a good match as well. VT100 or 50...BAT has a little different (and to me) better sound.