AirPlay 2 with multi-room audio playback from iOS 11.3 supported on tvOS 11.3 - 9to5Mac
Add AirPlay to Your Classic Stereo with an Old Apple TV - TidBITS
WiiM Pro AirPlay 2 Receiver with Voice Remote, Chromecast Audio, Multiroom Streamer, Stream Hi-Res Audio from Spotify, Amazon Music, Tidal and More : Amazon.ca: Electronics
Add AirPlay to Your Classic Stereo with an Old Apple TV - TidBITS
iOS 11.4 brings stereo pairs and multi-room audio with AirPlay 2 - Apple
How to Set Up a Stereo Pair of HomePods With Your Apple TV | PCMag
Apple TV 4K (3rd Generation) Review | PCMag
Apple's AirPlay 2 brings multi-room audio streaming to HomeKit and beyond | TechCrunch
Multi-Room Audio Setup with Arylic AirPlay 2 Amplifier H50
AirPlay 2 multiroom audio: Hands-on with the iOS 11.4 beta - CNET
Add AirPlay to Your Classic Stereo with an Old Apple TV - TidBITS
What is Apple AirPlay, and how does it work? - Android Authority