If it's mobile, you need to have that art car registered. If it's stationary, it needs to be associated with a registered theme camp that's already planning to bring that kind of sound to the playa (when you fill out the theme camp registration, there are questions pertaining to sound systems).
I believe the cap for sound systems that are not on the 2 o'clock or 10 o'clock spikes or the Esplanade... is 300 watts.
PM me if you're interested, and I can help you connect with some of the bringers of big sound to the playa. In the right place, your rig would be perfect