also, to turn around what Asonicyouth said. Krells sound very good with tube pre's (Sonic Frontiers) comes to mind and has the features you want I beleave. I use an Audioprism Mantissa tubed pre with my Krell. I have also used an Bent Audio TVC (passive pre) with my Kav-500 with great results...I tried it with my Ksa-250 also but not as good a match as with the KAV. I've read that the AR tubed pre's are also a good match with Krells, I think you can get balanced and HT pass-through with these older pre's also in your price range.
Dave
Dave
Dave
Dave