I have owned several HSU subs through the years, ranging from the dual TN-1220's, HRSW-12V, VTF-2 & 3, as well as the STF line. One thing I concluded time after time with the HSU subs is that they were more room/placement dependent than any other sub I have owned. I never could get the VTF-2 to sound good. It was boomy and undefined to me. all the others sounded good (NOT great) after much trial and error with placement, with the best of the bunch actually being the HRSW-12V. Now I am fortunate enough to own a Velodyne DD-15 and it only took 1 minor adjustment, placement wise, to have the best bass I have ever heard in my system. I used to really, really want to believe that HSU was as big of a homerun as everyone wrote about, but I never got to that point with mine.