Here’s a good deal: a big swath of Sonos’s speakers and soundbars are 20 percent off through Cyber Monday. The sale is now live at Sonos’s website as well as Best Buy, Target, and other retailers. Pretty much everything is at its lowest price ever, and while there are some notable exclusions — including the Sonos Roam, Five, and Sub Mini — it’s still a great time to fill out your Sonos system.