its called dtp. at least in lancaster thats what it. if they can hear it something like 50 feet away and pin point it to you, they can pull you over and cite you, and if you fight it, you'll lose. again, at least here in lancaster thats how it is. the issue isnt so much with the cops around here hating the loud music as it is that if they get a complaint, it pisses them off that they have to deal with it, so they make you pay. but most times, if they just hear it and pin point it, they will tell you turn it down, or if you get an angry cop, you get cited.
not sure on philly, and i imagine this is pretty general all around the us.
tint is another thing, as far as the state of pa goes, from what ive found from lawyers, jurisdiction cops and state cops, if it didnt come out of the factory with it, its illegal, of course, ive only heard of one person being pulled over for it.
refs: Oldschool4me, Derrick824