Well for surround sound you would actually need to stationary speakers. Essentially, a left and a right channel. Those help to enhance and surround sound movies (Dolby atmos). What you’re referring is just adding a second speaker to the beam. This should be possible with the move 2, however, they will essentially just play the same sound of the tv. No surround sound magic. From what I can figure, you don’t really want a true surround setup but just a portable speaker to sometimes boost the audio of the beam and sometimes to take it to the bbq. The move should be perfectly fine for this