Proximity of "Power cables and power cables is a problem". Huh? That makes no sense as they are energized identically and who cares after the 120v reaches the power supplies and becomes DC. I would keep signal cables away from power cables in any situation; audio, video, computers, anywhere.
How much space between cables is enough?
I understand that proximity between power cables and interconnects or power cables and power cables is a problem, but is there a rule of thumb as to how much space is required to NOT be a problem. 1/2", 1", 6"? Also, are all cables the same? I would assume that the higher the current, the more isolation, but belief and reality are seldom the same.