I am using Balanced 20' Granite Audio 470 four nines pure silver power cords for my Aerial SW12 subwoofers, which gave me further dynamics at several dB lower volume level than the DH Labs balanced BL-1 that I had been using. (the long DH Labs balanced cables are for sale) I use the same interconnects for my entire system as well. If you're interested in them, e-mail me, stevebruzonsky@cox.net,
as I can give you some info including how to get a big discount as Don of Granite Audio is a local friend in the Az Audiophile Society with me. I've found that his silver cabling really works well especially in long runs that I have in my home theater system to better and accurately convey the original audio signal.