Car Audio question pertaining to a particular infinity unit?

[Ian Gannon]

I was browsing a Crutchfield magazine a while back and I remember an Infinity product that just added the feeling of bass. It wasn't a subwoofer, but made it "feel" like there were subwoofers in the car. I can't seem to find that same product anywhere.

Anyone else know anything about it? Ever seen/heard about it?