Here's an excerpt from a previous thread on this subject:
There are numerous upgrade wires available for dedicated lines which I've read about (try to find those archive threads; Kimber is one definite source) but I used #10 solid copper THHN. Mike VansEvers gave me this idea which has worked so well that I'm just amazed.
You make up a bundle of black white & green conductors, all aligned with the printing running in the same direction. Fasten the ends of the bundle with electrical tape, clamp one end in a vice & put the other end in your variable speed 3/8" drill chuck. Slowly spin the bundle to wind it up like a spring; when you release power it will uncoil considerably. Then exchange ends & finish the twist. This twisted configuration is similar to the way many upgrade AC cords are made, it cancels stray magnetic fields outside the conductors. Lay the bundle in across the floor & connect it temporarily, then listen for awhile to test & determine which direction sounds better than the other direction. When you install in conduit or Greenfield, then burnish the exposed wire ends nice & shiny with crocus cloth (or an ink eraser in a pinch)& clean them thoroughly with Kontact, etc. Also shine up & Kontact clean the male prongs of your AC cords. Use a high grade outlet; FIM etc. Also consider isolated grounding. Your electrician won't understand any of this "audio nonsense" & will probably try to tell you that it makes no difference, but believe me it absolutely does. If you can get him to install a small fusebox & use a ceramic fuse (vs. glass) that will sound better than any circuit breaker. The newer plastic fuses seem to be OK too. He'll say you're insane but hey you're the paying customer so get it done the way that YOU want it done. Also polish & clean the fuse itself & any elecrical contacting surfaces in the distribution box.
Here's a link to a search of all archived threads on the subject of dedicated lines; read up!