I currently have 5.1 audio setup, and am migrating to 7.1 My question is what happens on non 7.1 movies / TV shows? Will my Denon 1909 sort of make it's own 7.1? Or, will it not even send audio to the 2 extra speakers?
If it doesn't send audio to the two extra speakers, then for the attached picture (don't laugh, it's bad), which set of speakers would be considered the rear's on a 5.1? 1 and 2 or 3 and 4? Normally it wouldn't matter, but I have a set of speakers that are better than the other set, so I want the better speakers where they will get more use.

If it doesn't send audio to the two extra speakers, then for the attached picture (don't laugh, it's bad), which set of speakers would be considered the rear's on a 5.1? 1 and 2 or 3 and 4? Normally it wouldn't matter, but I have a set of speakers that are better than the other set, so I want the better speakers where they will get more use.
