jim ,there are 3 models 300, 500 and 650 $ mine is the 500$ model. i am using an older 55watt jvc amp turned up about half way. i think mounting it under the couch is the way to go but i wont know till i try it. on dvds with action it is really better. rgh makes cheaper models. theres a good website on bass but i forget address. search for bass transducers and youll get it.