I Have A Sonos Amp 4.1 Set up with MA passive speakers + Sonos 1s surrounds. I am really happy, however I feel frustrated not being able to play Atmos music, recently I found a way I wanted to share, in despite than in my opinion most Atmos mixes are not worthy for me to ditch my current set up. I would like to hear from others which other ways you have used to achieve this. I recently listened the new Atmos version of “The Dark Side of The Moon” on Amazon Music and it is impressive, it was worthy to turn on the TV just to listen to this Album.
Anyway I will start a list of hardware proven to achieve Atmos downmix to 5.1:
My case : Fire TV 4K, Sony TV AF9 and Amazon Music HD feeding Sonos Amp. Amazon Music settings, Ultra HD off, Spatial Audio on; Fire TV set to Surround Sound Best Available. With this combination the Sonos app recognises DD 5.1 as feed from Atmos songs. I use the TV menu to turn off the screen as the Amazon Music app doesn't trigger the screen protector.
Previously I found that the Tidal App on the Sony Af9 would also play Atmos as DD 5.1 but not the Amazon Music app on the same TV.