Spatial Audio in Non-Apple Apps?
UPDATE: For Tidal I believe the answer is that Tidal tracks are pre-processed with a binaural head-transfer function and so they appear to iOS as being stereo tracks. However I compared the Atmos and MQA versions of Oxytocin by Billie Eilish from tidal and the atmos version clearly moves various parts of the mix up overhead, whereas the MQA version keeps the mix perfectly level with your ears as expected for a stereo mix.
So for Tidal at least, I believe the data flow is: Multi-Channel Source > Use Binaural Head Transfer Function to spatialize the channels and combine into stereo track (this step is done on Tidal servers) > Stereo signal send to iOS. This means tidal is using the same head transfer function for all users, and not able to leverage the personalized spatial audio in iOS.
For Apple Music, I assume what's happening is: Multi channel Source sent to iOS > iOS uses its own binaural head transfer function (which can be personalized with lidar in airpods settings) to spatialize all channels and combine into a single stereo signal > stereo signal sent to APMs.
If this is true then you should definitely NOT turn on spatialize stereo when listening to Tidal atmos tracks as you would essentially be applying the HTF twice.
ORIGINAL POST:
I just got some airpods (upgraded to latest 6A300 firmware) and am trying to test spatial audio on my iPhone 13 with latest ios 17 and M1 MBP w/ latest sonoma. It's been really hard. I've tried the following:
- iPhone - SpeakerCheck App - This is literally the only app i've been able to get to work. In control center I see the expected multi-channel audio logo:
- iPhone - Tidal - claims to be spatial audio in the tidal app, but in control panel music still shows up at "stereo"
- iPhone - VLC - tried .mp4 and .mkv files with dolby atmos and 5.1 audio tracks. Both show up as "stereo" in control center.
- iPhone - Prime Video - doesn't mention anything about atmost and control center shows "stereo"
- MBP - Tidal - no albums show the "atmos" logo and in control center it says "spatial audio not available". Thinking Tidal for mac doesn't support atmos.
- MBP - VLC - tried .mp4 and .mkv files with dolby atmos and 5.1 audio tracks. Both show up as "spatial audio not available" in control center.
- MBP - Prime video - no mention of multi-channel support. "spatial audio not available" in control center
Is there any way to get that "spatial audio" tag to properly show up in any app other than "SpeakerCheck" and apple music/apple tv? Super disappointing if so.