Yes, and no. :)
You can certainly “group” the two rooms, one the Ray and the other the Sonos One. However, due to the way that Sonos works, the sound from any “grouped” room with the Ray will be delayed by at least ~75 ms. So if it’s in another room, not really a problem. I used to do this with some PLAY:1s in my kitchen during football games, back when I wasn’t in a open floorplan.
But I’ve found that if that “grouped” speaker is hearable (read: in same physical room as) at the same time as the Ray, it’s too much like a stadium speaker when someone is trying to sing the national anthem. The delay is just too much for me to deal with.
That’s me. You could try it and be happy with it, my position is not to judge, just to give information.
Most people use a par of Sonos Ones (or in my case, the PLAY:1) as surround speakers, by “bonding” them to the Ray, but then they play surround information, and not the same center channel that contains voice, and that is, what I think, you want to do.
You could indeed group them, turn down the volume on the Ray, and have the One turned up, though….you’d just have that minor lip sync problem with the video.
Edit: Noted that I’m a slower typer than @jgatie :)
