I am very curious to hear what you have to say about buying this box - https://www.woofersetc.com/p-7421-sqp15spl-ground-shaker-15-single-ported-high-spl-box.aspx It would be going with a Sundown nightshade. The 4.2 cu ft. seem good and the box looks nice to me. I know building one will be a little cheaper but it probably wont come out as nice and would save me the headache of building one myself. But if you recommended that I just build one myself then that's what ill do. I emailed them asking what the tuning is so if its not around 33hz then obviously wont get. Also its not double baffled so idk if it will be strong enough for 2500 watts. Theirs also this http://cgi.ebay.com/4-0-CU-FT-CUSTOM-PORTED-BOX-fits-KICKER-CVR15-CVX15-/160554332666?pt=LH_DefaultDomain_0&hash=item2561c8b1fa And is double baffled and 4.0 cu ft tuned to 33 hz seems perfect. But just let me know what your thought for these are and if or if not I should just go with one of these or just build my own. Thanks

I am not a box designer, but I would say with a Nightshade and that kind of power I would want it double baffled and definatly some bracing inside.

If it were me I would want a double baffle. Single baffle on any high power, heavy motor style woofer is a bad idea due to possible flex issues.

Contact the Box Builders here on the forum for a qoute on a quality built enclosure.

Those boxes seem a little big. I usually see NS15's in around 3 cu ft.