Quote from the review:
What is it?
The ButtKicker, in simplest terms, is a bass shaker, but it can’t accurately be described in words. It has to be felt to be believed. It literally rocks your couch at just the right times during explosions, crashes, jet fights, or battle scenes in movies.
Does it work?
I was initially skeptical the ButtKicker would shake at the wrong times or be distracting. But the ButtKicker intelligently shuts itself off when no bass signal is present, which prevents unrelated vibrations and also saves energy. The ButtKicker remained off during most regular TV shows or news programs, which contain little or no bass. When it’s movie time, you will be pleasantly surprised how the ButtKicker jumps into action as soon as you pop in a DVD.
I had no clue that they made things like this. It might be some fun for when you have friends over.