The smaller satellite speakers handle the high frequencies and the subwoofer deals with the bass. These speakers come in the satellite/subwoofer configuration borrowed from the high fidelity home speaker market. The Sound Sticks II stereo speakers from Harman Kardon are no exception.
They bring all of their experience, design capabilities, and quality with them when they move down market. It is always great to see high end companies design products for the other end of the market.
Rainy Day Magazine : Gear & Gadgets - Harman Kardon Sound Sticks II