I've seen similar devices used in car stereo setups. To be very blunt, they suck. The idea is that instead of a speaker cone vibrating, whatever you attach it to vibrates. This creates several problems...
First, you are vibrating a random object to make sound. Since the resonance of this random object is unpredictable, the sound is very unbalanced. In other words, it sounds like crap.
Also, if there is even one screw loose in your cabinet, or you forgot to glue even one joint, it will rattle.
In conclusion, the product sucks. Don't waste your money and be sucked in by its ambitious claims. Sorry to burst your bubble.