Yes, you can use ethernet for MIDI connections for BomeBox. The default ethernet set up is as a DHCP client, so just disable WiFi and plug in your BomeBox into your router, disable WiFi by pushing the WiFi button until the LED goes out and you should be all set.
Using both WiFi and ethernet on a BomeBox simultaneously can be problematic if the network addresses are different. However if you set the WiFi as an access point and the ethernet as a DHCP client, things should work fine. The ethernet will be assigned an address by your router and that address will be the same over WiFi.
Any devices on ethernet on your same network will be able to see BomeBox.
If you connect one of your connectors from your BomeBox to your home router and the other to your iMAC, then the connections will be bridged to your home network as long as the ethernet is configured as a DHCP client.
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