Best PC for Krell FPB - 600 - 20 Amps

Looking for the right Power Cord for a Krell FPB-600 -20 Amps
If you have experience with PC's on the Krell FPB-600 , I would like to hear your suggestions and how does it differ from the factory PC.
I use the Pure Note Sigma on my FPB300. The improvement is quite amazing.
If fact it was recently suggested to me by an honest dealer that had the FPB400CX for sale, that I would be better off not upgrading to his amp because the new Krells do not allow the use of aftermarket power cords.

You can see my review of the Pure Note Sigma on this site.

I'm burning in Pure Note Sigma's on Krell 350mcx's right now. No complaints.

New Sigma's
I would contact Steve at and see what he suggests. His cables are among the very best. Tell him Ivanj sent you.
I also use the PN Sigma's on my Krell equipment. You need to put many hours on these for them to blossom. I have the 15-Amp version. Too bad the new Krell stuff is hardwired. Dan D'Agostino hates aftermarket cords, I guess he feels that he can do better.