Best Pre for Krell Amps


I am hoping to move on a 2 channel preamp very shortly to mate with a Krell KAV amp. My requirements/objectives are the following:

HT Pass through or Unity gain for same purpose
Balanced
Remote control
Tubes or SS
Avoidance of excessive brightness

Speakers will be either Wilson or Thiel and may change back and forth from time to time.
ckoffend
I am using a PS Audio PCA-2 with my 600cx and it sounds great. It absolutely sounds much better than the Aesthetix Calypso that I tried as well as an Audio Research LS-16 that a friend wanted to try out in my system.