Some of our clients that are upgrading to Sonos from Bose or expanding their older Sonos system, often ask what is the difference between Sonos 1 and Sonos 2? Sonos 1 and Sonos 2 refers to the 2 versions of the Sonos operating system. The original version, Sonos 1, is now known as Sonos Controller. Many older Sonos products are compatible with the Sonos 2 app. All new Sonos products released after May 2020 require the Sonos 2 app. The following products are not compatible with the Sonos 2 app, Bridge; CR-200, Connect Amp (Gen 1), Amp (Gen 1), Play 5 (Gen 1), and the Zone Players 60, 90, 100, 120, and S5. If all your products are Sonos 1 products, you don’t need to upgrade to the Sonos 2 app. Your system will continue to operate as is and will continue to be supported. If you have a combination of compatible older Sonos products and new Sonos products, you can use the Sonos 2 app. If you have a combination of Sonos 1 only products listed above, and Sonos 2 products, you can continue to use the Sonos 1 products as a stand-alone, separate system. For help designing your Sonos system, schedule a free consultation by calling 888-775-2673 or visiting our website @ www.wbsouth.com.