Why dual subwoofers ?

Using two subwoofers is often the cheapest way to increase your bass output, clean up any bass distortion, and add to the overall impact.

More importantly, using two subwoofers can help eliminate a lot of the bass problems you have in a typical room without using equalization. It won't be as effective, but it's sure a good start.

You get better responce across the listening enviornment. so it is easier to position them.

Also, subs are supposed to be "Non directional" well, this aint always so, if you park one near each speaker stereo sounds a bit better.

plus at the office you can say "I got dual subwoofers" and sound cool.

It really cleaned up my bass. Now it's infinitely more accurate and, for whatever scientific principle, less boomy.