Which Krell to hunt down on the used market?

Concerning neutrality, it's an over-used descriptive and generally intended as a positive attribute of a component or system. Yet many people prefer the musicality of tubes, which in most cases are not considered particularly neutral. I've heard people talk about Krell amps being neutral, like it's a really good thing. Yes it's neutral, but is it musical?. I found the less neutral MD series more musical than the more neutral FPB series. The added warmth through the midrange effected a tonal balance that suited my ears.
There really isn't a lot to think about, so don't strain yourself on my behalf. You want neutral?... go knock yourself out.

Rooze

I just purchased a vintage KSA-50 over one of the newer Krells. I love it! Several of the responses to this initial question imply that the newer Krell amps are more neutral than the older ones like mine. My experience is that this is true. However, I like the older, warmer Krell sound. And I think that the type of music one prefers also should be taken into consideration.

I found the older Krells grainy. I also found the sound difference between the FPB 200, 300 as compared to the 600 much more than just the power. The FPB 600 is IMHO a much better amplifier than the lower powered units. I ended up buying the 600 after comparing. YMMV.

How do the older very expensive Reference series KRS 100, KRS200 compare to the newer FPB series? Bob

Personally I like the KAS2. To my ears, they have both positives of FPB and KSA S Series. It is definitely better than KSA300S I have heard in every aspect, yet it has treble trasnparency character that FPB cx series has but in a lesser extent. For all new or old series Krell amps, I strongly recommend to give them a dedicated 20A line per amp. If you haven't done so, give it shot for a great treat. You may also conclude that it doens't sound anything like the anemic Krell sound that many have been complained about.