Hello. Please educate me. I am thinking of buying a new receiver to replace my pioneer vsx 515 to get more realistic sounds (and features). i have a pr. of jbl e80 towers as fronts, pr. bose 301 for surrounds and pr jbl n28ll as rears. What should i get? I looked at the yamaha rxv1600, 659 and denon avr 3805. Or u can recommend the best one and speakers upgrades to match. Thanks a mill. Oh my room size is approx. 12*15