The SUB-120 is one solid subwoofer. Packs a solid bass at even low volumes, and awesome kick at high power. Have had one for couple years with the initial system purchase of Klipsch F-300 towers, and added a second sub for even more kick. Well, after all it is Christmas, and the great room is very large. Klipsch speakers have demonstrated without question their expertise in the design of a really great speaker.
Hard to take out the "boominess" of this sub... prefer tight, deep bass vs. a more boomy mid-range bass... Have worked it tuning it to our living room. All in all, a very good subwoofer, made in the typical Klipsch fashion - excellent.