The Are Sealed, I fell in love with these, they are some of the most musical subs I have heard, for a theater I think there are more rumbly powerfull options for less money, but these would easily compete with any other 300w 12" sub for clearity.. I have my towers crossed at 100 and subs at 85, and it sounds excellent with all types of music.. They have remote controls that allow you to change phase, volume, and the crossover setting, as well as set presets, pretty handy....
So if I am listening to something where I like the crossover set lower and volume higher I can hit preset 1 which is crossed at 65 and volume 90, or something with a lot of female vocals and live instruments, I cross at 85 and have the level at 77 would be preset 2, and so on...
I have a black one brand new in the box for sale

regular price $999 or 1299msrp, Ill sell for $350!!!!