sonos play 1 & ray

Yes. Buy the Ray, then unpair the Play:1s. 

Once the Ray is set up, on its settings go to Connect Surrounds (adding the two Play:1s). This will add create a bond between the Ray and the Play:1s. 

You can then choose to play music through all the speakers (selecting ‘Full’ under Music in the Ray’s settings), or select “Ambient” to just play music on the Ray, with the Play 1:s adding gentle atmospherics. 

NB: You could just set up the Ray and group them manually with stereo paired Play 1:s, but the TV and the Play:1s will most likely be out of sync. Always best to bond a Sonos soundbar to the other pair (as surrounds) to keep them in sync. If the ‘surrounds’ are not behind you, then just ensure one is placed left and one is placed right in the room to get a decent stereo for music.

Nice thanks for the answer.
Another question will the speakers still be stereo?

Yes. As will the Ray (so make sure you place the speakers on the correct sides of the room or they will cancel each other out!) But it will ask you anyway during set-up which speaker is L and which is R.

Thank you very much, you helped me a lot

A word of caution, if I may.
 

Depending upon the tv audio signal, the Ray may think it’s receiving a stereo tv program. As such, there’s no “surround” data to send to the rear speakers since they are, in a 5.x setup, rear effects speakers. The decoder in the Ray (or Arc or Beam) has to process the signal and send the audio streams to the designated speakers.
 

When streaming a music source (Amazon music, Spotify etc) it knows it’s a music signal and distributes it to the rears as well as the Ray. 

I’d agree, the ‘Full’ rather than ‘Ambient’ setting only has effect when there is music coming in from a stream via your LAN, and has no effect while the input is coming in from the TV set. If the TV input is the active one, you’re dependent on what the signal coming in from that input is, and you have less control (mostly just volume at that point) over that signal to the rear speakers. 

What is the music channel that you want from the tv? Is it available from a streaming service such as Radioplayer or MyTuner? Then you won’t need the Ray. 

youtube(not youtube music)

Now I'm not sure I understand.. If I see a concert or a video clip on TV on regular YouTube I'll only hear what ray? Or in stereo on all speakers?

You’ll ‘hear’ the format that YouTube sends…which is likely to be stereo only, and as such, only on the Ray. When using the video (digital) input on your Sonos Ray, there is no way of changing the output of connected (bonded) surround speakers.

Even if you ‘removed’ those surround speakers from the Ray, and set them up in a separate Sonos room, there would be a slight delay of around 75ms when grouping them.

Unless YouTube sends a true stereo signal in the surround channel, there is no way to get the surrounds to play in stereo. As suggested, using YouTube music, while sacrificing the video, would get you what you want.