It's sounds (no pun intended) a bit daft at first but it's actually quite an efficient design. By utilising something that already exists and turning it into another useful feature, it eliminates excess weight of normal sub-woofer setups and at the same time it doesn't require the installation of additional speakers. Let us just try and explain how it works.
Using the large, and often concave, rear window of a car, Acoustivision uses a piezoelectric actuator to receive signals from the audio player. These signals are then transmitted along a series of springs that run along the base of the window, causing the entire window to vibrate in time with the music. Also situated at the base of the window is two exciters which help synthesize harmonics of the low frequency signals, simulating deep bass. An amplifier is also used to boost signals from 12 volts to 200.
It's a great idea really and comes with a couple of side benefits too. Magna International says the Acoustivision system is substantially better at keeping sound waves inside the car as opposed to a conventional boot-mounted sub-woofer - so no one around you is forced to listen to the same music as you, but also, the system is considerably lighter in weight compared to the heavy magnets associated with conventional sub-woofers.
The technology is not quite ready to enter into the OEM options list just yet, but it shouldn't be too long before a Mercedes-Benz S Class is fitted with a similar feature.