The Denon 3802 has surround speaker capability for A, B, and back. Reading the manual, it suggests that you can use the "B's" for 5 channel music (i.e. monopolar), leaving the "A's" plus rears for the 7 channel (recommending bi/dipolars). It seems as though it's possible to select both A + B speakers, so does that mean it's OK to have both A and B as surround sides, and surround rears for movies? (Giving a max total of 9 speakers plus a sub). Does the sound processing 'work' like this, and will the amp take the total speaker impedance? Any thoughts?