I integrated DD-18 with my B&W N802. Room problem was at 46 and 63Hz, so no other subwoofer will provide such precise equalizing as Velodyne. Only problem with DD is 1/3okt measurement, but I done it with other 1/24okt software. Anyway, it took allot of time, but on the end, you have flat in room response down to 14Hz!