I am now using a Denon AVR 4800 and a Yamaha RXV 590 to power my surround rear and to outdoor speakers by the hot tub. I would like to get rid of the Yamaha by upgrading to the AVR 3806 but I think I will still need another amp to power the outside speakers. The 3806 will power my surround rear however. Is this correct? If I still need another two channel amp to power the outside speakers who makes a nice thin one?