I am curious about bass shakers by the various companies that make them..Clark Synthesis, Aura, Buttkicker ..ect. I am not sure if I need them though since I already own an SVS 22-31 sub cornered in a mid-sized room. I mean will bass shakers help support all bass in movies and music or will it replace certain frequencies? If so, which frequencies are these? I was under the impression that if you have a good enough sub, that it would give you the same/similar effects of what bass shakers do for you. I have not been able to test out a system in an audio dealer just yet. I do know that my SVS will shake my couch if I have my playback level high enough.....any thoughts on this?