I must say from the start that my frustration lies with the DTS-ES and dolby ex sound on my system, I must confess that the placement of my back surround speaker is not the proper one, but here is What I found. I own a Denon 3801 which I love for its exeptional sound. Yesterday I connected a back surround speaker to take advantage of movies with DTS-ES and DOLBY digital EX sound. the speaker is placed in the same wall between my left and right surround speakers slightly higher and facing down, knowing that this is not the proper place but with no space, I had no options. But what I found was a thinner sound when the back surround speaker was engaged, not that it sounded bad, but it was to my ears not as big a sound, In all cases the sound was always fuller and showed more depth with the 5.1 than the 6.1 mode, specially on soundtracks with instruments like the violins which really soared in 5.1 versus 6.1. Some special effects sounded better on with the 6.1 configuration but always sacrifycing sweetness and separation in the sound. Could it be that the Denon 3801 is chikening out when more power is being drained from it or is it the placement of the speaker? Maybe I need to move to a bigger place. My system is calibrated with the Radio Shack meter and movies like Toy Story 2,The Hunting and Gladiator were used. Thank you.