I use a Crown PS-400 for the lows and a PS-200 for the mids & highs. These run in class A at lower levels and switch to Class A+B when the need increases. I'm very satisfied with them when driving efficient speakers like JBL studio monitors. Less efficient speakers may need more power.
I feel the K series might lack a little refinement on the high end for audiophile listening. ?
If you want to stay with Crown, you could look at the Studio Reference 1 & 2 amps. Most everyone who hears them say very nice things about them, but they are $$$$!
Tom