From https://www.reddit.com/r/xboxone/comments/7e81ax/dolby_atmos…
I'm not sure if you guys are aware, but Xbox now offers Dolby Atmos or Windows Sonic for ANY pair of stereo headphones. For Atmos, the Xbox app costs $30 but you get a 30 day trial and Windows Sonic is free. It is configured in the Audio Output section under Audio Settings.
I have a Turtle Beach XP500 with the headphone receiver connected via optical, but I can turn off the 5.1 processing (bypass) and let the Xbox send Atmos sound (by turning on the optical connection under the headphones section under Audio Output on the Xbox settings).
I also tried connecting my earphones ($600 custom IEM & Xiaomi IV Hybrid) directly to the controller (or using stereo headset adaptor) and received Atmos sound (with the optical connection setting turned off).
The audio sounds great in all cases and it seems that need for external headphone surround sound processors/receivers will no longer exist in the future.
Has anyone else tried it?