I owned a DD-12 in a room 18x20x8 with one wall of sliding glass doors. Quite the sub but I replaced it with a DD-18. No comparison (nor should there be because of the cost). The 18" sub is just super with anything I use it for... movies or stereo listening. My thoughts are if your even thinking of two (2x the dollars) get the DD-18. Its increadible. Move it around a bit in the room if you can (have help!), find the sweet spot and then utilize the software to tune it to the room. This is one great subwoofer!
Better yet get two!
By the way... Velodyne has a pass through for a second sub built in to their DD series.
Better yet get two!
By the way... Velodyne has a pass through for a second sub built in to their DD series.