I found an older pair of bookshelves, no brand on them, just a sticker that says 4ohm and the wattage. They sound pretty good and I plan on using them for the rear channels. Can I drive these with my 1015tx without putting too much of a strain on it? I figure they are only rear channels so they won't get much of a use anyways, its not like they are mains and are used constantly. But, if this is something I shouldn't do, I'd like to know if I need to run a seperate amp for them as I have a 100x2 kenwood amp I could use, but don't really want to. I don't have enough speakers to run 7.1 without them as I am selling my old HTIB system to pay for my new cadence sub, and 5.1 just doesn't cut it anymore.