Powercords for Krell 400xi ?

I'm looking for an improvement in depth, bass and lower floor noise. One's that I've considered are PS Audio, Blue Circle B62, Moray James, Micheal Wolff Gain. The Krell is already quiet but if at possible I'd like an even blacker background.

I have heard that an Elrod, DCCA or Electraglide would make the biggest impact,

can a PS Audio or Blue Circle give you most of what the big boy's give or do you really have the spend the extra dough?