Versions of this kind of request have been floating around the forums for years. So far, Sonos has not provided such a device.
If you were to use some sort of home theater preamplifier with five separate line level outputs, the delay on a Sonos analog line in would make this not sync up with the screen on your TV. I suppose if you were able to delay the video by somewhere around 70 to 75 ms, it might conceivably work, but you’d need to set up each of the five speakers as a separate room in the Sonos software, group them, and then do volume balancing to get them all sort of the right volume. You could potentially bond a sub to any of the speakers, but it would not ever be the LFE channel (the .1 in 5.1), since there is no way currently to feed a separate signal to a Sonos Sub.
