BRIDGE or BOOST are never required, but can be useful. BRIDGE is S1 only. BOOST can be S1 or S2. BRIDGE is nearing EOL (End Of Life) and many of them will cause intermittent issues. Use of SonosNet (the private SONOS mesh wireless network) requires at least one unit to be wired to the network. If there is no network connection near a player, BRIDGE or BOOST can be connected to the network and support SonosNet.

Here the list of S1/S2 compatibility.

I prefer SonosNet, but you can use WiFi. BRIDGE or BOOST have no function if you are using WiFi.

So I could use the Playbar, Play One SL’s and Sub for my living room on S2?

Then, since my bridge works well and I don’t have a player next to the network, create a separate Sonos system for the 5’s on S1 using the bridge for creating locations. 

Yes, this will work fine. S1 and S2 are two completely separate systems that can coexist on the same network. You could continue to use BRIDGE for the S1 units and BOOST or direct wiring for the S2 system.

If you do decide to go for separate S1 and S2 systems, turn off all S1 devices while setting up the S2 ones.

Ok great, thank you! Right now I do not have a boost, but I may not need it for my living room system anyway??

If you want to use SonosNet, you’ll need to wire something to the network. This could be PLAYBAR or a BOOST. Or, you could use WiFi.

Well, this so far is proving to be extremely frustrating. My existing system cannot be found on my phone. My wife’s phone, yes, the home computer, yes, my phone, no. I’ve reset everything, router, and as it turns out I didn’t have a bridge I had a boost so reset that as well. Unplugged every sonos product I have and it still won’t locate the existing system on my app.

This all started with buying play one SL’s to add surround to the playbar and sub, and now it’s a mess. 

It feels like a rubik’s cube, completely jumbled. 

Is your wife connecting via the S2 app?  If so, reset your S2 app.  Then choose Connect to Existing System.

Negative, she’s on the S1 app. I haven’t gotten to the point of deleting every connection point as of yet, but maybe that’s my next step. 

Maybe it is as simple as that. I need to delete all of the apps or forget the existing system on her phone and the family computer? I am trying to connect to an existing system with the amber app, not S1 controller.  

If her phone is connecting fine, its your app that is configured wrong. You need to reset the app on your phone:

https://support.sonos.com/en-us/article/reset-the-sonos-app

Then choose to connect to existing.

It’s been reset, deleted, reset, deleted many times. I don’t think that’s gonna do it. 

Make sure you are connected to the same WiFi band as her phone.

All same. 

If you are attempting to configure the S1 App, power down all of the S2 units. Likewise, while you are configuring the S2 units, power down the S1 units. You can also “reset” each of the controllers, but my preference would be to uninstall then reinstall the controllers. Take care to connect to the existing system. In my opinion it’s too easy to click on the wrong option here and start a new system.

I suggest that you refrain from Factory Reset of any SONOS units without further consult.

So far I have no S2 system set up. My wife’s phone sees the old system via the S1 controller. Through her phone all systems go, meaning I don’t see any issues and I can control all of the components. 

What I have done so far - Unplugged all of the Play:5 (Gen 1), Left only the playbar, sub, and boost connected, downloaded new S2 app on my phone. 

Now, the inability to find the network on my phone was present prior to me adding the new app. So the fact it can’t connect to the existing network was and is an issue on both controller apps. 

My intent was to disconnect the comps that could not be upgraded, download the new app, and upgrade the playbar, sub and boost to S2, then add my two new play one SL’s. Then set up a separate system with the 3X play 5’s via the S1 controller. 

Are you saying that your phone will not sign-on to WiFi? If so, you need to solve that issue before attempting to deal with SONOS.

No, I’m not saying that at all. My phone is on the WiFi, same as my wife’s phone. I don’t feel like I’m a complete idiot, just can’t figure out why Sonos won’t recognize the existing system. 

Nothing has changed on the Wifi, we’re on the same network, my phone connects fine to the wifi, just can’t connect to the Sonos system. 

Is your wife’s phone using 2.4GHz and your phone using 5GHz? If so, there is an issue with the access point not connecting the two segments.