Will this setup shield <> TV <> ARC also pass lossless atmos (local content) ? What do I need to look on the tv regarding passthrough codecs? Is simply having eARC HDMI in enough?

Depends on your TV, not the Sonos. Check with the manufacturer of your TV set. 

It depends on the TV, but if it does have eARC, odds are very high that it will.  ARC is a little iffy. 

Is there any inherent advantage to wall mounting the Arc versus sitting it on credenza or shelf below the TV screen?

I wouldn’t think so, given appropriate/equivalent spacing. There are no downward firing speakers. But, given that none of us own one yet, it’s pure speculation. 

Which LG set do you own? Because here I read the following:

https://www.rtings.com/tv/reviews/lg/c8-oled

Update 02/27/2019: While the TV doesn't support Atmos passthrough via a Dolby TrueHD carrier signal (common in Blu-ray disks), it is advertised as supporting Atmos passthrough via Dolby Digital Plus, which is the Atmos format used by some sources like Netflix; our testing confirmed this passthrough on the LG C8.

Really interested in the Arc and the new Sub, I have two Gen 1 Play 5’s, A Playbase and Two One’s at the moment. It would be good if I could get a trade in on the playbase /two play 5’s to upgrade to the Arc etc...not sure I want to go down ebay route - can Sonos trade up on multiple items?

What happens to the up firing speakers when you have the sub connected and play 5.1 content...do they get disabled? also what about the side firing speakers if you have rear speakers connected?

In that situation does it become a bigger beam with 3.0 sound?

The Sub places bass frequencies and does not change how the up firing speakers operate when bonded with the Arc.  The upfire speakers are playing audio when you’re not getting an atmos signal.  I believe they are supporting the front left and right channels.  On the side firing speakers, it’s my understanding that the their function changes when rear speakers are bonded, but they are also not disabled.

 If you have an Arc with a sub and rears bonded, you have a 5.1.2 system.  The Arc by itself is technically covering 3.0.2, but again, all the speakers are active and playing a role in the audio quality.

My sets a 2017 LG60UH650V, I've approached LG asking re Atmos pass-through 3 times to be sure as they weren't filling me with confidence that they knew what they were talking about, the 1st one said probably, the other 2 said it wouldn't pass-through but offered to escalate as a 'voice of the customer' complaint. Really want to order the full arc, sub and surrounds package to go with my whole house Sonos set-up but not sure it's worth it if I'm not going to get Atmos, I already have a 5.1 system that works fine.

Will Dolby Atmos music be available through Tidal’s HiFi tier on the new S2 app?

If the atmos signal is coming to the Arc through your TV, then yes.  Sonos has not stated that you would be able to stream Atmos content from another source.  As well, you won’t be able to get Atmos content playing on anything but the Arc.

Haven't seen it mentioned anywhere or in the product details but wondering whether the Arc has the ability to create psuedo Atmos sound with a non Atmos signal like some other set-ups can?

I currently have a playbar with the whole 5.1 sonos setup, and an OLED 2017 LG TV with Arc 2.0 ( no eARC). And after reading everything here I decided just to cancelled my preoder for the arc. 
 

I was happy with a digital version of the atmos anyway. But i use mainly an apple tv. But when i read that the apple tv will only send the full atmos signal then inmediatly i decided to cancel and wait until i figure it out everything. 
 

so i understand the sonos arc will play atmos in digital format if i use lets say netflix directly from the app on the tv. But not if i use it from the apple tv. 
 

but i was just checking this morning, if the apple tv is sending full atmos trough the hdmi cable. Then it means not even the internal speakers of my tv should detect atmos. But it is actually working. Does it means that because netflix on the apple tv is sending atmos in dolby digital anyway? So it means probably it will work with the sonos arc anyway?

lots of doubts here  

Ok, so having established with LG that my current TV won't support Atmos pass-through, I'm now looking at buying the following TV as it seems really good value, it supports Dolby Atmos and vision......can anyone see any reason why this won't allow pass-through of an Atmos signal to a Sonos Arc?

Philips 65PUS8204/12

Well … i have LG E7 from 2017. AppleTV is connected to the TV. Before buying Sonos it was connected to a Denon X3600 Atmos receiver, and Dolby Atmos from the Apple TV worked fine. But the E7 was a Atmos-model, so the may be why. 
 

I wouldn’t count other 2017 models out though. 

Now, this is not a consumer product and I’ve not found where to get it, or even how much it costs. But I’m betting this particular product is gonna cost a fortune if you get your hands on one. But as a proof of concept I think I’ve found an HDMI debugger that actually does what many of us wish to see in a consumer product; A box extracting audio from a standard hdmi signal and transmitting an eARC signal on a HDMI TX port. The box is an eARC protocol analyzer made by Simplay Labs called SL-870.

Just gonna put this out here, maybe someone smarter than me can google this further and find something a bit more accessible for consumers. I just wanted to share my finding as there’s apparently already products on the market that can do this hideous conversion.

I am a pre-release buyer. 

The announced release date for the Arc is just a week away. With everything going on in the world right now, I’m just wondering if Sonos is still on target to hit 10 June or if that date has been revised?

Has there been any word? 

I’m in UK.   

Really hoping it hasn’t moved

As they’re still running a banner saying ‘we’re shipping’ when I log in to this forum, it seems like a vanishingly small possibility that they’d need to delay. 

Well, my credit card was charged on Saturday (I pre-ordered 3 weeks ago) so I’m guessing they will start shipping imminently. 

I pre ordered mine on May 23rd however they haven’t charged my card yet , so wondering if it’s still on schedule . Hopefully it still is as this is my 1st sonos and can’t wait to get a hand on it , besides my TV is lonely too for last 2 weeks without a .

Ohhh my cards been charged this morning too so all seems in order! 

my status has changed to

‘Dispatch Acknowledged’

haven’t a clue what that means...but i’m hoping it’s a step closer to getting this delivered imminently!

I pre-ordered on 28 May & as of today (3 June @ 1400 CST) my CC hasn’t been charged & my order status is back ordered.