Those devices should work well together. I would also suggest you run ethernet for the TV and soundbar, just in case you need to hardwire them for any reason.

So, I have CAT6 ran to the room with the drop at the wall where the TV will be mounted. I can run a small ethernet switch for all the devices. Does the Sonos AMP require the ARCe HDMI to sync properly to the TV audio or is it through the AMP/ARC connection?

I’d suggest the Arc Ultra for the three front channels and height and Sub 4.

What are you going to use the passive speakers for?

Surrounds, one Amp would connect to the Arc Ultra to support that. You could Group the other to do a slightly delayed stereo version of what the Arc Ultra is playing in TV mode.

Music, one Amp could support all four (if they are 8 Ohms) to play music or Group with the Arc Ultra, which would be in sync for non-TV sources.

Two Amps if you want to play different audio on the two sets of speakers. Two if you don’t want both playing surround audio. A switch to kill one set when not wanted is also an option.

You can only have one device connected to the TV’s eARC HDMI so you’d have to pick the Arc or Amp, not both.

The Arc and Amp will sync perfectly over the network when the Amp is connected to the Arc as the surround channels and playing TV sources. When not connected TV signals will be delayed, non-TV music will be in sync.

Stanley_4 - So the passives I am intending to use as surrounds and yes they are 8 Ohms. To start I think I will use the singular AMP for all 4 speakers, but the nieghbors don’t NEED to hear what I am watching, so I figure I will get another AMP and have it support the pool speakers individually… 

thank you for the suggestions!

I thought so, but wanted confirmation from someone that has owned or worked with Sonos before. Thank you again