I know were not supposed to start multiple threads about DIY projects but I was wondering if anyone has seen this sub at PE before. (http://www.partsexpress.com/pe/showd...number=299-665) I did a search(to see if it has been talked about) and many DVC subs came up but none that came up in the pictures of the subs was this sub. I was going to go with an atlas 15" But this sub has 2 mm more xmax, much higher rms..... is the fs too high? It has 37hz fs. 21 hz for the atlas. Does that mean it won't play below those frequencies or it is not safe for the sub below those frequencies? I know fs plays apart in dictating how low a sub can go I just don't know how it determines it.