Ok, I have been on a similar quest a while back. I was trying to get Atmos from the tidal app and tried many different ways. Discovered that only a few devices are capable of delivering Atmos. Fire stick max, apple tv and Nvidia shield were the only ones that seemed to work. Connecting to the HDMI input of the x3700h will give you the Atmos music experience. Be prepared to be disappointed. I listened to dozen different albums hoping to be impressed and lost interest. Maybe someone else can recommend a good album to demonstrate the potential.
Cold Cold Heart - Dua Lipa and Elton John was better. I think maybe Shallows (Bradley Cooper and Gaga). Other than that, what a disappointing experience at least with headphones and Amazon Prime HD. I clicked on an Atmos playlist and went through song by song comparing. At least 75% were better without Atmos. Not just a bit better usually, a lot better. The Atmos reminded me of the "bad" surround options on an AVR. Fake, mushy, etc. I suspect it will be, like digital in some ways, a long road as people learn how to use it to make things better not just different.