Apple, Amazon and Sonos multi-room audio systems compared
Sonos 2 Room Set with Roam Portable Smart Speakers
Sonos Roam review: true portability adds value to Sonos's ecosystem | What Hi-Fi?
Amazon.com: Sonos Four Room Set One SL - The Powerful Microphone-Free Speaker for Music and More - Black : Electronics
Amazon.com: Sonos Two Room Set with All-New One - Smart Speaker with Alexa Voice Control Built-in. Compact Size with Incredible Sound for Any Room. (White) : Electronics