Sure, why wouldn’t they? The speakers are on your LAN, the controller is as well. 

Thanks for your reply,

I have a diagram connection like this

I have some other questions:
1/ I connect all 3 Sonos One SL to the Switch as shown above, will there be any network problems? (Because I saw some other posts saying that when they connect multiple Sonos devices to the network, problems can easily occur)

2/ Can I use Sonos S2 App on Desktop to group all 3 Speakers and Stream Spotify music to them? Is it possible to adjust the volume independently for each one through that S2 App on the Desktop?

Also if you have any advice please let me know, I really appreciate it.

1. use an unmanaged switch.
2. Yes.

Currently I am using the Managed Switch type because I need to manage the connection between other devices (Desktop, Printer,...). Can all 3 Speakers connect directly to this Switch or do I need another solution?

Why exactly do you need to “manage the connection between other devices”? Keep life simple, use an unmanaged switch. A managed switch will cause heartache to your Sonos system, and to you.

Sorry I haven't mentioned enough details,
Because we need remote access for this site to support our work, we need to use a managed switch.

The use of this type of switch had been decided before, so I had to follow that to deploy the Speakers accordingly 

Check with your IT department, Sonos isn’t really built for many work environments. Several issue are 1) the controllers and speakers need to be on the same subnet, and 2) RSTP issues, which is where the managed/unmanaged issue creeps in. There are likely others, too, I’ve never ventured into a ‘Sonos at work’ install. There’s a reason why they advertise a ‘whole home’ solution, although there is now Sonos Pro, something I’ve not looked in to. 

We have a Desktop at that site to install the Sonos S2 app, which will definitely be on the same wired LAN.
As for network equipment, there are:
- Comcast Business Router v2 (CBR2) Model- CGA4332COM
- NETGEAR 26-Port Managed PoE Gigabit Switch (GS724TPP)

I checked the above two devices with Sonos's incompatible network hardware and both are not on the list.

https://support.sonos.com/en-us/article/incompatible-network-hardware
If so, can I connect as described?

You will likely need to configure the Netgear switch for STP/RSTP.

https://support.sonos.com/en-us/article/configure-stp-settings-to-work-with-sonos

You may need to do other things, good luck and let us know how it goes.

Thank you, if there is any update I will let you know 

Is there a reason why wifi would not work in your chosen environment? I’ve seen people being scared of wifi radiation on this forum being very disappointed that Sonos speakers cannot be made to stop emitting Low Energy Bluetooth signals that are used for set up. could this also be a problem on your work site, or is the cabled connection chosen for other reasons?

The problem is that the Speakers are quite far from the Wifi coverage area, and the people at that site do not want to use SonosNet.

Therefore, I had to choose the solution of having 3 Speakers plugged into the Managed Switch.

Hello guys,

While waiting for purchase approval, I want to ask a little more.

1/ Once I have finished setting up the Speakers and added them to the group. If I use the Spotify App on that Desktop, will it recognize the Speaker group I set up from Sonos and play music to that group?

2/ At that site, they want to have a main operator and a backup person (so that when the main operator is busy, this person can play music instead). Can I use one Spotify account to sign in on both Desktops? Do I just need to install Spotify, or do I have to install the Controller App and sign in to a Sonos account on this backup person's Desktop?

You’ll need WiFi while you setup the speakers because a phone/pad must be used during setup. You could setup up where there is WiFi coverage, then deploy them in their final locations. Set your switch for STP, not RSTP.

Wiring one or more units to the network will enable SonosNet. Any mixture of wired and wireless is supported on SonosNet. Up to 32 controllers can be simultaneously in use, any mixture of wired and wireless. Controllers, wired or wireless must have a connection to the SONOS subnet. The PC controllers, wired or wireless, can be used to play music, but have limited ability to configure the system.

Note that ROAM and MOVE are WiFi only.

Any combination of players can be Grouped to play the same music. It would be possible to use Airplay 2 if the iPad/iPhone has a WiFi connection available. Bluetooth is not supported on SONOS ONE’s.