The comments about the combination of Krell + B&W being a match made in hell, I think it is more to the room and also the amp or speaker model. I used to have Krell KAV-300i driving B&W CDM 1SE back in the day, more than a decade ago and it wasn’t that bad. As a matter of fact it’s rather good. The exemplary traits of the Krell are a big, bold and dynamic delivery with deep punchy bass. The bass of the Krell is really something special, it hits hard with raw energy and power. With other amps the bass sounds like a soft thud in comparison, more subdued with reduced kick and dynamics. Thick carpet/rug and proper speaker placement will also help tame the brightness in the room.
The OP did not reveal the Krell amp model which he owns yet though. If it’s the KAV-400xi I heard it’s warmer sounding and more neutral.