Agree with Jgwilson, good quality and clean AC power is a fundamental requirement for good overall sound. Power cords do make a difference.The point is 'all' cables are important and have a sonic effect.
Which Cables Are of Most Importance?
In a hi-end system, McIntosh, B&W, which cables will give me the most bang for the buck between IC's, speaker, power and HDMI? Which cables are most important and which are least important? Will concentrating my $$ in any one or two cables give me the most bang for the buck?