Wow, what a great system. I googled your pre-amp because I'm kind of in the market for a tube pre-amp. Well, I won't be getting THAT one any time soon! Pretty spectacular.
I've got one dedicated 20amp circuit which I use solely for my power amp, a Parasound Halo A21. Instead of agonizing over the choice of a power cord and receptacle, I simply wired a Wattgate IEC plug direct to the breaker! I didn't use fancy wire, just thick. It's a stranded 3 pole 8AWG cable compliments of Home Depot. Sound is fabulous.