using play 5 as stereo pair with sub and as surrounds for 5.1

Not without going through the bonding/un-bonding process each time. But you can set the surrounds to 'Full' instead of 'Ambient' for music sources. This will give you full volume output for the surrounds as well as the Playbar when playing music.

Thanks for the quick reply, will they be playing in stereo when set to full just with the addition of the play bar?

How easy is it to switch fro Ambient to full every time.

I was just going to get 2 play 3's and a sub to go with my play bar but have the opportunity to get a newish play 5 for the same price as a new play 3 so was thinking of getting one more new play 5 instead of the 3 play 3's

Yes, they will play in full stereo along with the Playbar.

The switch is automatic. When playing the TV source, they will be surrounds. Any other source, it will switch to full. Not useful if you listen to music via the TV source, but it works for everything else.

thats great thanks for all the help, in you opinion if i can get a cheep play 5 is it worth the extra to get the other or just get the 3 play 3's instead?

I wouldn't get the Play:3s. Play:1s are more than adequate for surrounds, and since you have a Sub, that will handle the bass. But the Play:5 is out of this world for sound. If you can get a deal, even better.

On the Play 5 make sure they are of the same generation, 1 or 2, so you don't run into issues with bonding them.

Also, I believe only gen2 Play:5s will work for surround sound. A lot of cheaper gen1 Play:5s around these days, but it sounds like those won't work for what you are looking for.

Yes only the gen 2's can be used for surround. I have an old gen 1 in another room but would be getting 2 gen 2's

Would it be possible in the same room to

1.have the playbar bonded to sub for 3.1 from the TV

2. For music have a stereo pair of play 5 gen 2 bonded to the same sub?

Would it be possible in the same room to

1.have the playbar bonded to sub for 3.1 from the TV

2. For music have a stereo pair of play 5 gen 2 bonded to the same sub?

Although maybe not in your case, but if that were allowed I could see a big potential problem for Sonos systems in homes with more than one user. What would happen if the systems were in adjoining rooms and sharing a common sub, and then two people played different sources? You'd end up with the sub getting two signals at the same time.

For that reason the sub can only be bonded with one system at a time.