Use the two Ones as rear surround speakers for the Arc/Sub to create a 5.1.2 home theater system. The Ones will connect as surrounds to the Arc wirelessly without needing the Amp. Then set up the Amp/pair of speakers/turntable as a separate zone. You could then group the Amp setup with the Arc setup when you want to play the turntable audio through your 5.1.2 system.

Thanks for response. Just to be clear, the Amp + speakers + turntable zone uses my existing wired speakers - and my ordinary home theater system would no longer use the wired speakers, right?

And if I can group the two setups for playing the turntable audio through the 5.1.2 system, does that mean the line-in being is actually not disabled in this system, correct?

I didn’t state this earlier, but if the system would support it, I don’t need to keep using my wired speakers. 

Thanks again!

The Arc will replace your Amp/wired speakers so the Amp will no longer be part of your home theater setup. Therefore the Amp will not be used for surround speakers leaving the line-in port enabled for your turntable.

You don’t have to have any speakers wired to the Amp/turntable, but you could keep the pair of speakers wired so you have the option to use them with your turntable or to stream any other music from the Amp. The Amp basically turns your pair of wired speakers into another set of Sonos speakers.

And since the Amp/wired speakers/turntable would now be a different zone, you could move this setup to another part of the room or anywhere else in your home.