I was wondering if anyone here has ever built their own sub. I am tinkering with the idea and have been on avs and home theater shack trying to learn as much as I can. I was also wondering if you can use different subs together to smooth out response. I would like to build a big boy sub that goes very low. I was also wondering if anyone has ever taken an ep 500 and built a bigger box for it. Would this help it out? Will it help with its extension or will it hurt the amp? If anyone has built one what would you recommend.