While yes, that basement subwoofer was pretty big, I guess, it was no Matterhorn. The Matterhorn is the most powerful subwoofer ever created. It was commissioned by the military for some reason (Friday movie nights at boot camp, perhaps?), and saying it's bass overkill is underselling the thing.
It's built into a shipping container (yes, a subwoofer the size of a shipping container) and it pumps out 40,000 watts of power. You read that right: forty thousand watts. Yeah, that'd piss off the neighbors if you had it installed in (or under, or next to) your living room. But man would it make the explosions in action movies really rumble.