Next week I plan to upgrade my set-up from 5.1 to 6.1 using 2 more speakers for the surround-back channels (Mission 77ds). Just out of curiosity, would it be safe if I added two more speakers for the surround left & right channels, adding the total number of speakers to 9? Heres what the 9 speaker set-up would consist of: 1: Front-left. 2: Front-center. 3: Front-right. 4: Surround-left. 5: Surround-left 2. 6: Surround-right. 7: Surround-right 2. 8: Surround-back L. 9: Surround-back R. I know the manual for the AVR-3802 states that the amp can output 105W for 7 speakers but if I added extra two speakers, would it put too much strain on my amp?