My room has a 3.1 speaker system so far, with the speakers placed near one wall, and it sounds good. But I would like to have some sound coming from the opposite wall (8.5 feet away). Would it be ok to place to more speakers on that opposite wall? Is my room too small and the extra 2 speakers would actually make the overall sound quality worse? I need opinions before I try because my only option is to place them in-wall if I do.