Also, a word about "shielded" power cords. Manufacturer supplied power cords, if they are shielded (and most aren't) must have the shield connected at both the AC plug end and the equipment (or IEC plug) end. That is a UL underwriting requirement. Good for your power saw, bad for your audio -- instant ground loop!! So, if you feel your equipment might benefit from a shielded power cord, get an aftermarket one with a floating shield and no UL rating.
One place I absolutely recommend using a (floating) shield power cord is the DAC, CDP, or DVD. These devices tend to broadcast digital RFI from their power cords unless they are adequately shielded. They also pump digital RFI into the electric lines, so put them on their own circuit, or use a power conditioner which has a couple of outlets with digital filters specifically for this purpose.
One place I absolutely recommend using a (floating) shield power cord is the DAC, CDP, or DVD. These devices tend to broadcast digital RFI from their power cords unless they are adequately shielded. They also pump digital RFI into the electric lines, so put them on their own circuit, or use a power conditioner which has a couple of outlets with digital filters specifically for this purpose.