NONE...these amps don't require anything, that's why you'll be able to give it to your son and he can give it to his! they are battleships! The only thing is the lights on the front, I'm not sure if they made a LED kit for this amp, ask audio classics. Otherwise you would have to change the Lamps inside if they are going dim (they all do) these lamps are made by a company called Chicago Miniature. Or have audio classics give it a check up and change the bulbs if you want. AWESOME AMP!
Matt M
Matt M