I am going to build my own box for my subs. I am going to have 2 12in V-Max's and 2 15in V-Max's.Should i make it one large sealed box and make it as big as i can,or should i port it? If a ported is good how would i go about making it? can i make it one large box and port it like in the midle or do i need to seperat the subs and port them seperatly? And should i sperat the 2 12s and the 2 15s in eather one of the aplications?