My first recommendation would be the Cardas Golden Reference for speaker cable. In my opinion the Cardas Golden reference speaker cable has everything you are looking for.
My Second choice with your system would be the Monster 2.4 speaker cable.
You may find the Monster 2.4 speaker cable very engaging with the Krell amps. I owned a set of the Krell FPB/250 mono block amplifiers and found the Monster 2.4 cable to be very engaging.
Also, I would take a look at the power cords and line conditioner you are using and perhaps make a change.
My Second choice with your system would be the Monster 2.4 speaker cable.
You may find the Monster 2.4 speaker cable very engaging with the Krell amps. I owned a set of the Krell FPB/250 mono block amplifiers and found the Monster 2.4 cable to be very engaging.
Also, I would take a look at the power cords and line conditioner you are using and perhaps make a change.