One thing that hasn't been mentioned is cooling. Make sure you have a way to exhaust whatever enclosure houses your components. Even if you have them stored remotely, be sure they can breath. A/V receivers and satellite receivers put off a lot of heat. Don't get me started on Playstation 3s. I have two a/c powered fans on an IR plug that is turned on and off with my Logitech Harmony remote. I also have a component fan that pulls the hot air right off the A/V receiver and feeds it to the exhaust fans. They are all quiet and I don't doubt that they have extended the life of my components.
Previous: 1993 Prostar 205
Red 1998 Ski Nautique, PCM GT40, 310 hp, , Acme 4 blade, Perfect Pass SG/Zbox.
Be kind. Have fun.