Considering a separate amplifier for (5) 4-OHM bookshelf speakers. Would like to learn some information before I make a purchase. I am Currently driving them with 6/8 OHM rated AVR. The room is 12x12 wondering how I would benefit by adding a separate amp to drive these and if it is even worthwhile for my application. Basically, would I have a noticeable difference? Any recommendations or suggestions would be appreciated.