Setup Separate S2 on Same network as existing S1 without effecting then entire S1 setup.

So you’ve read this? https://support.sonos.com/s/article/4845?language=en_US

Sonos seems to say a reset of all the S1 devices is needed. Your idea would be different, where you would shut down the S1 devices and then set up the S2 One?

I do not think just turning off the Connect that is setting up Sonosnet will disable all others -instead they will search for the network, while you are setting up a new one. You really need to take the speakers off power to shot them down.

Yes i read that article. That i believe assumes you want to move all compatible S2 products to S2, and then put the S1 products back on an S1 app. That is not what i want. I just dont want to upset the existing setup whatsoever.

Then I would take all devices that need to stay on S1 off the power before setting up the newOne.

Ok, i’m still a little nervous to see what will happen when i turn them all back on.

Has anyone else done it this way?

Well just took the punt, i did speak to Sonos Support again and they said to turn all the old ones off too. So far so good, have S2 app working on the One SL, and when i plugged the old ones back in, they are all still on S1. 

No strange prompts yet but will keep an eye on it.

That was brave!  I’m glad it worked out and it may well be helpful to others.

Just out of curiosity, if you wouldn’t mind sharing, what do you gain from keeping this speaker on a separate system?

I have to upgrade anyway in the next couple of weeks as im going to get a Beam, Sub ,One SL set with upgrade credit and wanted to test the two as ill make my grannyflat S1 with Play5Gen1 and One, and then the rest can go to S2 in the main house, all still on same network. I read there were issues with Google and streaming services cutting each other out with the separate s1/s2 setup and so far my Youtube Music streams perfect on both systems at the same time even though i dont have family membership which is great.

Thanks for replying - that all makes perfect sense.

I run two S1 systems and one S2 system on the same network. No issues after setting it up carefully.

Just be careful with it.  I got a Roam to try out and my S2 app lost it and offered to “find my system” and then the S2 app proceeded to hijack the S1/S2 compatible components on my S1 setup, while also never finding the Roam,  and I’m having to reset them all, losing all the settings on 5 components, and set them up again from scratch - some are mounted up high, some paired, some room tuned - it’s a fair pain in the ass.  Now I’m pretty paranoid about an S1 and S2 system on the same network and I have too many components to upgrade the entire thing.  So I think the Roam has to go back - too bad, it sounds decent for the size. Nice work Sonos. 

@stevepow Posting almost the same message in four threads (Join the discussion, ask questions | Sonos Community) does not help in solving your problem - possible solutions will be put in different places on the forum. Plus it should not be possible that your system upgraded without you telling it to, so your problem might not be a problem for every user. 

I added a new Roam to my S1+S1+S2 system yesterday and it went seamlessly. Hardest part was the NFC tap to pair it.