In 2020, new wireless capable music device should be supporting Airplay 2 protocol. The protocol now supports multi-room music play across devices from different brands. Improved stability over the first gen Airplay protocol. However, one of the question without easy to find an answer is, “does it now support Hi-Res audio?”
What is Airplay?
AirPlay is a proprietary protocol stack/suite developed by Apple Inc. that allows wireless streaming between devices of audio, video, device screens, and photos, together with related metadata.
Wikipedia Airplay
Basically, it is a wireless connection standard/technology that allows Apple device e.g. iPhone, iPad, MacBook etc. to send audio and/or video to target devices that support the Airplay protocol.
The benefit here in original version were obvious when compared to competing technologies/protocols like Bluetooth. From audio stream stand point of view, bluetooth protocol have limited bandwidth and did not even allow CD-quality audio to be played while original Airplay allowed CD quality audio streaming.
Although Wifi streaming is what’s behind the Airplay technology, the benefit over Wifi stream is that the device does not have to be on the same WiFi network when playing music over Airplay.
What’s new in Airplay 2?
Compared to the original version, AirPlay 2 improves buffering; adds streaming audio to stereo speakers; allows audio to be sent to multiple devices in different rooms; and control by Control Center, the Home app, or Siri,functionality that was only available previously using iTunes under macOS or Windows.
Wikipedia Airplay
What’s Hi-Res Audio?
The definition is any audio file with greater than CD quality. CD has a 16 bit audio bit depth and 44.1 kHz sample rate so any file utilizes any combination beyond these two numbers are technically considered Hi-Res Audio. Most common are either 24 bit/96kHz or 24/192kHz, and less commonly 24 bit/48kHz. But even 24 bit/44.1kHz is considered Hi-Res as bit depth is above the CD while sampling rate is same as that of CD.
Does Airplay 2 support Hi-Res Audio?
Now we are going to investigate about this.
After spending sometime searching on Google, Forbes states following:
Apple’s AirPlay 2 protocol downsamples audio files to 24-bit 44.1 kHz
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This number is supported by the fact when I stream Amazon Music HD to my Airplay 2 capable speaker, the device capability changes to indeed 24-bit/44.1 kHz.
One astute forum member on Sonos community discovered (here) one slide showing by Apple (35 minutes) states 48 kHz sampling rate possibility. So it would have had made more sense if numbers above were 24-bit/48 kHz, but the presentation were from 2017 so perhaps design change before final release.
So technically speaking, Airplay 2 is capable of Hi-Res audio but sampling rate is limited to that of CD. More common 96kHz or 192kHz are not supported.
So technically speaking, Airplay 2 is capable of Hi-Res audio but sampling rate is limited to that of CD. More common 96kHz or 192kHz are not supported.