Synergistic Research Euphoria HC power cord.

@bwguy I haven’t tried this cable but tried their lower end model and it was a bit too lively to the point of being bright plus it was super rigid and difficult to maneuver. It exhibited the same sonic traits on everything I tried it on…dac, preamp, amp. I sent it back. I wouldn’t be looking at Synergistic but that’s just me.
I looked at your system photos and there’s very little in terms of acoustic treatments so go easy on lively sound

Also, if you are talking to The Cable Company and thinking of buying from them, use their landing library and borrow several cables to try (you get credit towards purchase after).
I’d look at Audioquest Hurricane or Dragon, Shunyata Alpha and Sigma, Audience FrontRow.
Shunyata and Audience will be most flexible if that matters at all.

I disagree with Jason. But like I said, their landing library is the way to go. The only way you’ll know if the cable is a good match is to try it in your system. I would also wait until the panels are in place before making any changes at all. 

@bwguy McIntosh amps are detailed and open sounding. Your B&W D tweeters are resolving and airy. I’d be looking for a power cable that just allows these qualities to shine in the best possible way. It’s really easy to tip the balance in the wrong direction especially in a system like yours. 
What interconnects and speaker cables are you using?

Sorry @soix I have to disagree. Speaking of dark sounding cables - Krakatoa and even more so Gargantua. Owned a few of each with different components running different speakers over a period of about a year and always the same effect. Fat, slow and sounds like a bowl of overcooked oatmeal.
I’m a huge fan of AZ interconnects though (Matrix Ref Mk2, Silver Ref Mk2, Absolute Copper and Absolute Silver) but just can’t recommend their power cords. 

I’d stick with the top players in the pc game - AQ, Shunyata, SR, Audience. Add Transparent to the list. Try and buy whatever sounds best.