John Darko
What do we know? When it comes to Apple’s AirPlay, we know that a digital audio stream travels through the iPhone or iPad on its way to the streaming endpoint. We know that those same digital audio streams are handled gaplessly; but that higher than CD-quality audio isn’t possible. Some of us also know that devices like the AppleTV and Samsung’s Tizen OS internally upconvert 16bit/44.1kHz audio to 16bit/48kHz upon arrival over AirPlay.
Most of us know that there are two flavours of AirPlay: AirPlay 1 and AirPlay 2. How do we tell the difference between AirPlay 1 and AirPlay 2 endpoints? Inside iOS, a naked tick means our iPhone/iPad is talking to an AirPlay 1 endpoint and a tick inside a solid circle indicates an AirPlay 2 endpoint is in play.
Last year, thanks to the diligent work of Darko.Audio Patron Brother Thomas, we learnt that all AirPlay streams – v1 or v2 – sent to an AirPlay 1 endpoint are transmitted losslessly but that – wrinkle alert – AirPlay 2 transmission has a split personality. When transmitting to an AirPlay 2 endpoint, a streaming app developer can choose between AirPlay 1 and AirPlay 2 output modes with the former resulting in a lossless stream but the latter a 256kbps AAC lossy re-encode. Uh-oh.
Let’s summarise for the sake of simplicity:
AirPlay 1 app mode –> AirPlay 1 endpoint LOSSLESS
AirPlay 2 app mode –> AirPlay 1 endpoint LOSSLESS
AirPlay 1 app mode –> AirPlay 2 endpoint LOSSLESS
AirPlay 2 app mode –> AirPlay 2 endpoint LOSSY
One app that operates in AirPlay 2 transmission mode is Apple Music. Stream Apple Music to an AirPlay 2 endpoint and the digital audio is re-encoded by the iPhone or iPad to lossy AAC before being sent onwards. Tidal on the iPhone or iPad used to work the same way but a recent email from Brother Thomas suggests that the iOS Tidal app has been recently been updated to now transmit in AirPlay 1 mode. Hello, lossless digital audio transmission. That’s good news. SEE UPDATE HERE.
Brother Thomas also points out that the developer of the Raspberry Pi operating system RoPieee has added a toggle switch to allow users to switch between AirPlay 1 or AirPlay 2 receiver modes. That’s useful for Apple Music subscribers: click the RoPieee OS over to AirPlay 1 and enjoy a lossless audio connection between your iPhone and your Pi. Yum.
Then there’s Roon, who only yesterday rolled out an update that’s been a long time in the oven. Its server software now supports AirPlay 1 and AirPlay 2 to ensure a) proper functional compatibility with stereo-paired HomePods and HomePod Minis – which need to see AirPlay 2 streams – whilst b) maintaining the lossless audio of AirPlay 1 transmission mode when talking to other AirPlay 2 endpoints.
https://www.instagram.com/roonlabs/p/C8us_m6OEtv/?img_index=1
