How large do you think the largest automotive subwoofer ever made is?  How about 22″ wide, and...get this....369lbs!  The sound this thing produces is bone-rattling, teeth-chattering, and heart pounding!  every person on your block will hear you advent a mile away.  Here's what Mtx says about it:

Mtx Jackhammer, the Largest Subwoofer Known to Man

"Designed from the ground up to be the most weighty subwoofer ever, JackHammer incorporates radical new technologies. It is even man-made in Mtx's convention facility with a magnetizer constructed just for this woofer-a magnetizer that wipes out any credit card that dares come within 25 feet! JackHammer is the Biggest, Baddest, Boldest subwoofer...ever!" 

Billed as the subwoofer that "other woofers have nightmares about," the Mtx JackHammer is a 2-foot tall, 369-pound behemoth that makes you proud to be an American. This 22″ subwoofer handles 5,000 watts Rms (up to 10,000 watts peak), and features a 900-ounce (that's a wee over 56 pounds, folks) magnet and a 6.5″ voice coil. The JackHammer is set up for high Spl (Sound Pressure Level), but you can buy an replacement cone assembly that allows you to switch swiftly to Sound potential operation (and you don't have to remove the speaker from its enclosure to make the switch). There was a constant crowd nearby this woofer throughout the show, jaws open, staring in awe as the woofer cone moved in and out. Sometimes excess is a good thing!

Car Stereo