due to the size of the box i want to stay local but i have a custom built ported box for 2 15". It's my first build so it may not be absolutly perfect but it did make a difference in the output of my subs. I also have 2 what i'm assuming to be busted, idk they seem like they play when they want, 15" RF p3's. I also have a sealed - prefab box for 2 15's. If intrested let me know