He's exact words (in email that is) are:
"To me the most important component is a good powered sub. It's the component that gives you the most bang for buck in a good setup.
To compliment the sub, attach a subharmonic processor. This will give you REALLY beefy, deep low end.
They're pretty cheap ($99) and will really set your home theater apart from most others...."
I might be wrong, but my response to him would be.
A good quality subwoofer like an SVS, HSU, JL Audio, etc. A subwoofer with the proper design will give tight, controlled, accurate, and outstanding performance. And most of these subs have the ability to go as low as 10Hz-16Hz.
Also keep in mind that proper placement is very important. And IMO will add the most "Bang for the Buck" in performance.