hello im new to the forum world but i like to read them to help me in my decisions. any way i have a mint pair of realistic mach ones and i have a spare set of woofers that were given to me. i would like to use the spares for subs so i was going to build a pair of sub cabs to match the mach's. here is what i am thinking it would be very easy to just copy the mach cab minus the horn enclosure but i was thinking of building a ported enclosure. problem is i don't know enough about how to get my volume and port size so i was wondering if anyone out there can help me? maybe they would just sound better in the original sealed dimensions?