Beam gen 2, mini sub and era 100’s ethernet cable help

Wiring the Beam is not required, Sonos recommends Wi-Fi unless it presents problems. Do NOT activate the Disable Wi-Fi option as that disables the radio needed to connect Sub and surround speakers.

It is recommended to not wire Sub or surround speakers as it can cause issues with the direct, low latency 5 gHz wireless connection needed for synchronized sound.

If I understand correctly though, if my beam is wired alone. It creates a Sonos network of its own separated from my actual WiFi network? I will go ahead disconnecting the sub using the Ethernet cable. 

Depends on your settings.

When wired a 2.4 gHz  Sonosnet is created, by default, that will connect other Sonosnet compatible devices into a really old standards wireless mesh network, usually far less capable than modern Wi-Fi. 

If you wire and then disable Wi-Fi,  then the Sonosnet, 2.4 mesh and 5 gHz Sub and surround radio is disabled.

If you wire and select disable Sonosnet then the 2.4 mesh is disabled but the 5 gHz is left active so the Sub and surrounds can connect.

With multiple connection connection options you can create network issues with loops and data flows. Possibly worse if you haved managed switches. Best avoided, the Ubiquity topics here have some mitigation stratigies.

Well, this is quite interesting! I’m actually probably doing more harm than good wired up. I will just go full on wireless and see how it goes. I have a newer WiFi 7 router and should not have a problem. Thanks for the input and responses.