They are enclosed to some degree..THe plexiglass behind the speakers was cut specifically to create the sealed enclosure, the ports allow some airflow, but not enough to kill the sound. With this setup, sitting in the car blows your head off, but passing patrol cars are none the wiser... NY has strict noise polution laws, i would know, i've violated most of them with previous cars
My old Volkswagen
All the Boxes for 12in i looked at were not fitting flush in that space at all... which is why i opted to go a different way...
Oh yeah anyone notice that the back seats Really destroy the sound of anything in the trunk???