What Power Cord for Tubed Preamp

About a month ago I made my first foray into tubes. I was not satisfied with the rather sibilant sound coming from my system. I thought that this might be a good "excuse" to try out a tubed preamp. What a difference. My system has never sounded more musical. Even my wife commented that the SACD player/tubed preamp was warmer and more natural. Well, anyway, my question is, what power cords have you found to be beneficial with tubed equipment? I know that cables are system dependent. But I want a place to start my search. For digital I use Marigo Labs Ultra series II and the CPCC model 11 for my power amp. Here is my equipment list:

Sony C333ES SACD player
Audio Experiment Symphonies tubed preamp
B&K AV6000 power amp
Paradigm Reference Studio 60 Loudspeakers
Home Grown Audio Super Silver Interconnects
Ted's Excellent Cable Speaker wire.