I have Paradigm in walls that sound great on a 2 channel system with a sub and I run them full spectrum. They have 6 1/2 woofers and metal tweeters. I understand the new Axiom Audio in wall / on wall speakers are very good. I also recommend the PBH in walls, they make one with two 6 inch woofers that sounds great. Get some sound deadening material to insert into the wall cavity to deaden the sheetrock. I got this special mat that sticks to the sheetrock, I cut it into pieces and reached in as far as possible to line the space. I forget the brand. It had a peel off sticky side with a deadener backing like Dynamat layered on tops is an acoustic absorbing foam.