I just finished one last year and ran four dedicated circuits to the audio area, 1 at 30 amps for the amplifier and the rest at 20 amps, should be enough. I used P&S outlets. Consider a whole house surge protector. Also, I would recommend lots of fiberglass in the walls. Maybe investigate the feasibility of in-wall bass traps (I don't know if that would even work due to reflection off drywall). If the room will or could in the future be used for HT, you may want to run wire from a binding post jack in the wall to the ceiling for surround speakers. Finally, the thing I forgot to do is to run a subwoofer cable to the rear of the room for HT bass, fortunately I was able to pull it between the floor joists above the basement drywall ceiling. Have fun.