That is actually one of the cool things you can do with Sonos - run a left from unit and a right from the other because of the way they sync with each other. I've made stereo pairs from the Play 5's for outdoor parties before. Not sure how good a critical comparison between L and R speakers would be, but what do I know?

And to answer your previous question - with the Sonos Amp unit there is no unamplified output except for the sub output.

Dan
On-Wall M5HP LCR, QS8 & EP500 in 7.1