Dedicated Lines and Wall Boxes

The basic concept is to have any source of electrical interference from your home eliminated, therefore the logical answer is single runs. Use the larger guage wire so it will handle 20 amps in case you get into really big power amps. That being said I had to use a multiple outlet for 2 dedicated lines 2 outlets in the box one one dedicated circuit. Therefore allowing my one other piece of equipment to potentially interfere. I had to use an electrician and this was done for financial reasons. Like Albert and the others I found a minor improvement. I guess my electricity was rather clean to begin with, and have not experienced any interference with this set up. If you can afford to be a purist and you have grungy electrical interference from other household electronics in your circuit it makes sense to go with completely seperarate lines.

Dbld:
From what little I remember from physics electrical energy is firstly derived from large magnetized generator motors (powered by fossil or nuclear fuel) and that all electricity creates a magnetc field around it which is obviously very low energy. Other than that I would have to forward your question to my Eletrical engineering uncles one of whom is a professor in that field. Let me know.