I was thinking of maybe putting 3 12's in my car but the set-up would need to be a compact design. is this even possible? at first i had this great idea of making an equally sided triangle box with one 12 on each side. however, in order for it to have the sub mount depth deep enough, the box would need to be huge. anyone know of or have any ideas on another compact 3 12's box design? the total room id have to use is 43 inches wide X 24 inches deep X 15 inches tall.