Krellman is right. I have been pretty much a Krell user most of my time with this hobby (although not having the illustrious models Krellman has used) and the current Krell gear is very differently voiced from the older Krell gear. The Vanguard is in this new vein - more musical and forgiving, less visceral. Most importantly, the traditional bass slam that Krell is known for is no longer there. In the place of that is a more textured bass. Highs are slightly rolled off (not such a bad thing with some recordings), PRAT is no longer as good and the sharp transients and leading edge is much diminished. I am referring to the older main Krell line (and not the KAV line which sounded lighter and leaner). The FBI would still have the older sound. It really depends on what you like.
Just my 2 cents.
Just my 2 cents.