I'm fed up of having to put up with the limitations and price of commercial subs on offer today, so I've decided to see if I can do any better Having had a fair amount of experience with carpententry, box making etc. I feel that part would be easily accomplished. However there are many other factors involved that can be made easier by the help of program to calculate box volume and design. Does any other DIY'ers out there know where I can get such a program? In case you were interested, I'm looking at using components from BK Electronics and specifically 2 x BSB 10" 500 or xls 10 and a mf1000. Any thoughts on the direction to take this?