Room is 9300 cubic feet. The living room, dining room, kitchen and entry way are all open with 14' ceilings. Behind the listening posiiton is the dining area with windows. Current system is a Yamaha RX-V575, Klipsch KB-15 bookshelf speakers, Klipsch KC-25 Center and a Klipsch SW-350 8" sub. I'm looking to upgrade all. I was looking at the Denon x4100 or Marantz sr7008 but a forum member steered me towards the Denon 4520 from accessories4less and I think I might go that route. I'm looking at either Def Tech SM65, NHT Classic 3, Ascend Acoustics Sierra 1 or Paradigm Audio Studio 20 v5 for LCR. I purchased an SVS PB 2000 last year and returned it because my little 8" Klipsch blew it away! I even verified setup and troubleshooting with SVS tech. I can't explain why the SVS was so horrible but I'm willing to try again. I'm looking at purchasing a new sub or subs. The PB13-Ultra is $2000 so that will be my price limit. I am open to all brands. I was leaning towards 2 XV15Se from PSA at first. Any help would be appreciated in helping to narrow down the best sub (s) for my space and soon to be equipment. Thanks.