Search Google, there has to be a site somewhere for those window-rattling-S.O.B.s to share ideas on how to annoy homeowners and other motorists. Fortunately, the police started chasing them down about a year ago now, kind of rare in my neighborhood now.
Either there are some cheap ways to do this, or these guys sink all their money into it, considering the crappy cars they tend to drive around here.
Personally, I wouldn't think packing that much power into a small space would be good for your hearing, even with the earplugs I see them wearing...