Sonos Playbar + Sonos Connect Amp + 3rd-party In-ceiling Passive Speakers + 3rd-party Active Subwoofer in 5.1?

No sorry, you cannot do this because the subwoofer port on a Connect:Amp is inactive when that C:A is being used for surrounds. This is not Sonos deliberately disabling it, but because surround speakers connect to the Sonos system as 'satellites' to the Playbar, which runs the show.

However, I think the new Sonos Amp will change that, and should be rolling in to the store soon. I know it no longer needs to be connected with an ethernet cable, I'm just not sure if it will feed a 3rd party subwoofer.

TruePlay tuning will not work with any non-Sonos speakers in the "room". Sonos has said that they're working with Sonance and that you'll be able to TruePlay when there are Sonance speakers connected to the Sonos Amp.

No sorry, you cannot do this because the subwoofer port on a Connect:Amp is inactive when that C:A is being used for surrounds. This is not Sonos deliberately disabling it, but because surround speakers connect to the Sonos system as 'satellites' to the Playbar, which runs the show.

What about the Sonos Playbar + Sonos Connect Amp to the 3rd-party In-ceiling Passive Speakers + Sonos Connect to the 3rd-party Active Subwoofer? Can I get a 5.1 setup with this?

However, I think the new Sonos Amp will change that, and should be rolling in to the store soon. I know it no longer needs to be connected with an ethernet cable, I'm just not sure if it will feed a 3rd party subwoofer.

TruePlay tuning will not work with any non-Sonos speakers in the "room". Sonos has said that they're working with Sonance and that you'll be able to TruePlay when there are Sonance speakers connected to the Sonos Amp.

Woah, curious where you've read that the new Sonos Amp will allow 3rd-party speakers and a 3rd-party sub connected to the same Sonos Amp in a 5.1 setup. Do you have a link to where it says the new Amp will do this?

Also curious to know how the Sonos Amp can detect Sonance speakers vs other 3rd-party speakers.

No sorry, you cannot do this because the subwoofer port on a Connect:Amp is inactive when that C:A is being used for surrounds. This is not Sonos deliberately disabling it, but because surround speakers connect to the Sonos system as 'satellites' to the Playbar, which runs the show.

What about the Sonos Playbar + Sonos Connect Amp to the 3rd-party In-ceiling Passive Speakers + Sonos Connect to the 3rd-party Active Subwoofer? Can I get a 5.1 setup with this?You cannot connect a Subwoofer to the Connect.

However, I think the new Sonos Amp will change that, and should be rolling in to the store soon. I know it no longer needs to be connected with an ethernet cable, I'm just not sure if it will feed a 3rd party subwoofer.
I am not 100% sure but I would be very surprised if the subwoofer connection will be active on a Sonos Amp used for surrounds. HOWEVER, I would expect it to be active on a Sonos Amp used to drive the front speakers. But then, of course, you would need passive front speakers and the Playbar would be redundant.

Here is the definitive answer from Sonos staff member Ryan S, on another thread:

'The Sub can only be bonded to a single Sonos room. A single Amp or a pair of them will count as a single Sonos room, so you can't bond multiple Sonos Subs to it. If you're using a single Amp, you can bond a Sonos Sub with it, and use the subwoofer output to connect a non-Sonos subwoofer as well. I believe they'll both use the same crossover frequency settings. A Sonos Amp that is being used as the rear speakers for a home theater setup (with any Sonos player) has the subwoofer output disabled.'

The reason for this is simple. Amps are two channel devices with a crossover to the subwoofer out. The subwoofer in a 5.1 setup is its own channel. There is no way to combine the 1 distinct sub channel with 2 distinct surround channels and route them to a 2 channel device without ruining the mastering of the soundtrack.

There you go, more information from folks smarter than me :)

If you're looking for data about the upcoming Sonos Amp, read this thread:

https://en.community.sonos.com/announcements-228985/introducing-sonos-amp-6812069

The reason for this is simple. Amps are two channel devices with a crossover to the subwoofer out. The subwoofer in a 5.1 setup is its own channel. There is no way to combine the 1 distinct sub channel with 2 distinct surround channels and route them to a 2 channel device without ruining the mastering of the soundtrack.

Are you one of the Sonos engineers or are you basing this knowledge simply from the fact that the specs and back labeling of the Connect Amp doesn't say "LFE"? If so, and that labeling is correct, then the new Sonos Amp also isn't LFE for the Sub Out. Dang...looks like I'll have to tell one of my clients that their expensive Klipsch sub is now useless and they'll have to get the Sonos Sub.