You could do this, but to be honest I think you’d be better off moving all the Sonos devices onto SonosNet (and wired where possible) rather than mixing SonosNet and WiFi. As a mesh SonosNet enables all the Sonos units to intercommunicate directly, which as well as providing extensibility can improve performance in groups (and pairs) compared to a hybrid arrangement.

There won’t be ‘interference’ as such on whichever channel you select for SonosNet so long as you choose 1, 6 or 11 for your APs. Devices will cooperatively share the channel, and assuming low usage by the IoT devices they won’t demand much of it.

On the other hand you say all the Sonos devices work fine as they are, so why fix what ain’t broke?

Thanks @ratty 

I think maybe I’m misunderstanding SonosNet, but in my situation I am using ALL of 1, 6 & 11 - I have 2x AP on Ch1, 1x AP on Ch6, and 2x AP on Ch11. As I understand it, SonosNet will set up on one of these channels, so how wouldn’t this create interference?

When multiple devices and APs share the same channel they do so cooperatively. (In essence they look before crossing the road.) It’s when wireless uses different, and overlapping, channels that interference sets it. Typically 1, 6 and 11 don’t mutually interfere so long as the APs are decently spaced out.

So SonosNet will use CSMA/CA like regular WiFi to avoid creating too much interference? I assume any mesh maintenance traffic between the SonosNet devices is fairly low as well? My next concern I think would be that the placement of the wired Sonos devices may not be optimal for setting up a network. I placed my APs specifically to allow for best coverage. There would be many instances where a wireless Sonos device would get a much better connection to a regular wifi AP than a less well placed SonosNet device.

SonosNet is essentially WiFi at the lower layers of the stack, so in terms of physical co-occupancy of the channel it’s the same as any other WiFi device.

Idle mesh traffic is low. A regular pulse of small Spanning Tree Protocol packets every second to maintain the topology, and the occasional exchange of info between nodes.

It’s up to you, and as I say I wonder what problem you’re trying to solve if everything works as it should. If you truly want to create a ‘Mixed Mode’ setup then wire the chosen Sonos nodes and disable their “WiFi” (i.e. SonosNet signal) in the controller app. The wireless units will fall back to WiFi operation (WM:1, or WM:2 for home theatre satellites). 

Thanks again @ratty 

A couple of really good points.

You’re 100% right that I have no Sonos problem that I’m fixing - it’s more a case of wanting to remove as much traffic off the 2.4GHz network as possible as my IOT/Home Automation devices are ever growing in number!

Now that I understand SonosNet a bit better (with your help), can I paraphrase your point by saying “it’s better to have SonosNet on the same channel as Wifi where CSMA/CA will be used to share the bandwidth than on a partially overlapping channel such as 3”

Lastly, on the way to turn on mixed mode, i.e. ethernet connected, and wifi setting turned off, I suspected this might be the way to disable SonosNet, but wasn’t certain as it’s not well documented what this setting exactly does. (and it’s slightly misleadingly labelled as in my view SonosNet is not wifi)

One final question if I may…

The most likely devices that I would wire in are my sounbars (a mix of Arc, Beam & Playbar) - if I wire these devices and “disable wifi” - this shouldn’t affect the connection to the surround speakers / subs should it? My understanding is that from soundbar to surrounds and subs the connection is via a 5Ghz dedicated channel which is neither SonosNet nor regular 5GHz wifi?

Am I right?

Thanks so much.

FWIW. In my own experience in the past, when using a multi-access-point WiFi setup at Home, I found it best to stick all wireless AP’s on one ‘fixed’, least-used, non-overlapping 2.4Ghz channel (usually channel 1 in my case) with a channel width of 20MHz like @ratty mentions. I set SonosNet to the other least-used channel (Channel 11) - obviously my neighbours like to use channel 6.

All SSID’s/Credentials, channels and channel width, were always identical on every AP.

I set the 5Ghz to operate in the same way too (Channel 40 in my case) and left All to use a channel width of 20/40MHz though it was fine with 80Mhz aswell. I never had any issues with the setup ever. 

One thing I will just quickly mention is that my TP-Link AP’s had their own App, which did not allow a user to change channel-width, but fortunately they do also have a web-browser interface, which allows that setting to altered, in case that may perhaps assist others with their own hardware.

Absolutely. Partial overlaps are seen as noise/interference on both sides. SNR falls and packet loss can readily set in. 

Don’t get me started! A number of us have been commenting for years that “disable WiFi” is misleading terminology, resulting in users mistakenly thinking they need to do so after switching to SonosNet mode, and ….

Yes it would. It disables all the wireless on the device. This is often where users who “disable WiFi” after wiring an HT master speaker come unstuck. 

In your case if you did so the HT satellites would connect to the 2.4GHz WiFi instead. The roundabout route from the HT master would introduce latency spikes and the satellites would be likely to drop out.

Yes, you are correct about the HT Wifi, you should not disable the wireless adapter on any main Sonos HT product, such as a Playbar/Beam/Arc etc; if using it with ‘wireless’ surrounds/Sub, as it’s 5Ghz adapter is needed to communicate with those surrounds/Sub.

Edit: @ratty beat me to it - leave their wireless switched on.

Great - thanks to both of you for that last answer. That settles it - most of my surrounds couldn’t be wired, so my choice would be simple - leave everything as is, or wire some soundbars, but leave SonosNet enabled.

For regular wifi, I’d be surprised if this doesn’t create problems, or at a minimum some delay when a client roams from one AP to another. Probably works great for fixed devices, but do you find mobile devices roam OK? Or these days most mobile devices are probably connected to 5GHz anyway, which I assume you don’t use the same channel numbers on your APs?

Yes, I had no issues using iPhone/iPad/Android tablet - they just need to be connected to each AP one time (just a case of re-entering password - first connection only)  and after that I had no issues moving about the Home at all. I have iPhone XR and iPad Pro (3rd gen) as my main controllers and a generic Android 10 (64 bit) tablet. 

Edit: I do have all connected to the 5Ghz band and the 5Ghz channel (set to ch 40) are set the same on every access point too and same 40MHz channel-width (although 80Mhz is fine too). So all things set identical to the main router ..and all ‘fixed’.

Actually WiFi devices roam best when the APs are on the same channel -- and with the same SSID/encryption -- at least in my experience. Unless there’s a centrally managed hand-off between APs the device has to do all the work, so making it as easy as possible makes sense. I should note that my mobile devices use 5GHz AC, so the bandwidth of the shared 80MHz channel is not an issue. 

Fair enough. Whatever works I guess. I can certainly see some logic here, but still probably not the best setup in my case. With (literally) hundreds of devices connecting on 2.4Ghz the other reason for me to use multiple non-overlapping channels is that more bandwidth is shared amongst fewer clients - ie I have 40 - 50 clients on each channel rather than 120+ all on one channel. Not only is this a bandwidth benefit in my setup, but also (in theory) reduces contention, and therefore latency.