powered subs are made to help conserve space. so if you want a compact setup go powered but you wont get as much power as you could with a separated setup.I'm an audio newb. I was browsing through crutchfield and came across "powered subs" and I think it said its a sub and amp combined? If thats the case, would I still need to buy an amp or can I just buy one of these "powered subwoofers"