I have 4 AV15's on the way, but only want to use 2 for this project. I want to build a ported box approximately 700L internal volume like Jame's Dual Tempest "THE BIG PIG"(If anybody knows how to get a hold of James, I'd really like to talk with him about his design) and HTF's Bryan Michael also has made one that does just about what I want my sub to do. I’m trying to use WinISD but am getting different results than Jame's ended up with (WinISD shows it to produce lower dB's and to build it with shorter ports). For the amp, I won't say cost is no issue but if it requires a certain price tag to do it right then I won't skimp. I would like to get down to 16hz or even lower while maintaining an output that could frighten small children and adult alike I have planed on using 3/4" MDF then laminating it (good/bad idea?) Like James' sub I think that the walls will need to be braced. This will be my first home build speaker of any type but really enjoy DIY projects. Any advice/direction would be greatly appreciated and thanks.