The simplistic statement by, once again, our eric squires, says it all. Purchasing the " correct " ones, and the " set up ", is the key. Subs ( Wawa, makes excellent Hoagies, and this is what they are referred to ) are needed in almost every situation, ime, but getting them to " match and blend " with the main speakers, and the room, is the ticket. I tried running my Lascalas, with a crossover, but based on my listening, I prefer them to run full range, and allow them to taper, naturally, on their own, and bring my built pair of subs in, at that point, where it is the most seamless, to me. I do not hear the subs as a separate entity. Took a lot of time, and work. Test tones with spl measurements can be a wonderful tool, as well as selecting a recording or two, that you feel, is truly wonderful, at that " transitional " point, between the mains, and subs. There are subs, that only excel with home theater, and subs, that only excel with music. Of course, there are subs, that excel at both. Anyone who simply plops down a sub or two, might find it great, but believe me, adjusting, and readjusting, tweaking and some more tweaking, can truly get you phenomenal results. Enjoy ! MrD.