Four-HomePod surround sound has been rumored for a while, but the restrictions on what hardware is compatible is tighter than we wanted to see.
HomePods for home theater
HomePods for home theater
Apple is pretty clear about what’s needed for that surround sound.
“Users can enjoy room-filling audio with a single speaker, in a stereo pair, or using multiroom audio. When paired with the new Apple TV 4K, HomePod mini 2 supports four-speaker surround sound — Apple’s most immersive home theater setup yet.”