Yes absolutely.  You could set the Amp and ceiling speakers as surround speakers to the Arc if the ceiling speakers are suitably positioned.  That would appear as a single ‘room’ in Sonos and would sync perfectly for TV and music.

Alternatively you could set up the Amp and Arc as separate ‘rooms’, and associate the Sub with whichever you choose - Amp or Arc.  You can play one or other or both independently in this set up.  When grouped they will sync perfectly for music but not for TV - there will be an echo effect.

You can switch the AMP from surround mode to standalone mode (provided Sub is associated with the Arc) but it is a bit of faff, especially if you Trueplay tune each time.

Great thanks for the quick response John

 A SONOS system is organized as “Rooms”. A Room can be a single speaker, a “Bonded” pair of L/R speakers, a soundbar, or a full surround room. SUB can be Bonded to any of these sets.

Any combination of Rooms can be “Grouped” to play the same music and all members of a Group will be time aligned.

Surround sound with a TV presents a challenge for the time alignment because one wants to align sound with the picture (this is known as “Lip Sync”) and members of a Group. When playing TV sound from a soundbar, you can fuss with the surround sound Lip Sync delay and pick the best compromise time alignment vs Lip Sync. Note that this is a non issue unless you are listening from a position where you can simultaneously hear surround and regular Rooms. For example, if you are playing TV audio from a sports broadcast out on the patio, you’ll never notice a time misalignment, but you may want to tweak things if you have an open plan kitchen-living room with a surround area and there is a separate Room for the kitchen.

So I sort of have this setup.  I moved and brought my rather nice JL e110 Sub with me. I purchased an Arc and One SL.  I want to use Arc for front/center, SL for rear and JL Sub as sub.  So I purchased an Amp.  After HOURS of frustration, where it wouldn’t let me add the Amp to the same room as the Arc/SLs (only a Sonos Sub), I had to create the Amp+JL Sub as a separate room.  Then I have to group them together EVERY SINGLE TIME I want to play music or use TV in that room.  Further, I don’t think I can truetune that room with those grouped.  It kinda works, though pretty sure there’s a delay that I’m not smart enough (or don’t have ear) to fix.

Sonos, if you read this, PLEASE let us more cleanly integrate third party powered subs with your Arc/SL Ones.

Edit: I’d love to know why an Amp can’t be “bonded” to the Arc/SL combo, especially when it’s only powering a sub.