Last night on Myth Busters, they were exploring the possibility of blowing a car apart from the inside using pure volume.
They fabricared a 56" woofer out of metal plate and used an inner tube as a surround. Diaphram was driven off of a Mercedes diesel drive shaft cut and reconfigured like a crank shaft. The "piston rod" is what actually drives the diaphram. No volumes control (full stroke with every revolution, and frequency was determined by engine speed. Speaker did ~165 dB at ~16 Hz before it blew the sunroof out of the frame and the speaker self destructed.
JBL was there to oversee the project with their BIG VAN system that uses many, many W15GTIs and thousands of watts to get interior volumes over 165 dB in the driver's position. The levels in the passenger position are so loud, JBL will not let anyone sit in there during demo for fear of disarranging their internal organs.
Well you guys know my view on using W15GTIs in the home.