My father's birthday is coming up (in 2 days, okay, so I'm going to be a bit late with this--he'll forgive me). His current "subwoofer" is a Cambridge Soundworks unit that is, in my humble opinion, both wimpy and boomy at the same time. When I lived there I thought it was great, but I have an SVS now, so I've unavoidably become a bass snob. I want to get him a new sub, and I'd rather not break the bank doing it. The three I'm really looking at are the Hsu VTF-2, the Adire Audio Rava, and *possibly* (but not likely) an SVS 25-31CS. The problem with the SVS, of course, is that it's passive, and the old receiver that he has currently stored in a closet somewhere produces only 80w per channel. Plus he doesn't really want to have another receiver cluttering up the theater area if he can help it. I would really appreciate any feedback from people who have heard any of these subs (particularly valuable would be people who have heard ALL of them). I tend to doubt he would notice the difference between any of them, especially relative to the difference between his new sub and his old one, but I'd like to make sure I'm getting the most bang for the buck. I know I can't really go wrong with any of them, yeah yeah, but if there is a difference I should know about, I would appreciate hearing about it. Also, suggestions for any other subs that I have not mentioned are welcomed. Go ahead and muddle the waters a little further. Thanks for your input!