Help me with preamp choice.

Many people run the other way when you mention a passive. I have heard other passives with the typical shortcomings often associated, so I can understand why.
I do not perceive a loss of dynamics with the Placette Passive and it sounds more transparent and detailed than the active preamp it replaced that was 4X the price.
The cd player I had when I changed to the passive also had 2v on the RCA outputs. I can verify this combination is awesome and would expect it to rock your world with the Krell and VMPS.
The Placette will reveal any weak link in your system and you will hear the difference in cables and cords very easily. Use short interconnects, 2m or less. Read this:
http://www.placetteaudio.com/QandA.htm

I would strongly suggest the Adcom 750. There is nothing below $3k US that will touch it. It offers both passive and active operation, is a Nelson Pass design, and offers both true balanced and s/e operation. There are several for sale for $750 US here on A'gon. There are also simple mods that will make the active option untouchable. Pocket the difference and get some new cables!

OOOPS!!! I forgot to mention Adcom GFP750. Ivanj, right on!
Don't spend too much on cables for passive preamps. AudioQuest DiamondBlack tended to work the best with passives. You can also get VanDenHul Type2. I've never heard F.T. audio but in general terms you simply ought to try any passive v.s. active that is 2x or 3x the price of passive and see the result. After that I'll guarrantee that you will forget about using active preamp.

Hey IvanJ...good suggestion, but for $1500 he could buy himself a used Pass Aleph P with remote (even better, and the design that inspired the Adcom model).

I would also recommend checking out tube preamps. The above suggestions are good, and I'd also add a used Counterpoint SA-5000 to your list (it has a phono pre too, if that matters).

Passive is the only way to go. Try Placette's passive line stage.

bf