Saw something about atmos bitstream as I scrolled the pages. No, you do not have to bitstream to get atmos, well, kinda’. This can get messy for some with an XBOX or Apple TV.
All streaming services are serving up atmos metadata in a Dolby Digital Plus 7.1 track. It’s lossy and compressed and can be bit streamed over ARC and optical. I s#%t you not, atmos can be sent over optical when they squeeze the f#%k out of it.
Now, for anybody with a TV or streaming device connected to an atmos capable AVR, no big deal, UNLESS the device is connected directly to the TV and is an Apple TV 4K or new XBOX. Those two devices DO NOT bitstream Dolby Atmos but instead wrap it up in an uncompressed LPCM box and tie it up with a little f#%kin’ bow of atmos metadata. That f#%kin’ box chokes ARC and the TV and AVR must support eARC to get atmos. They call this bulls#%t Dolby MAT. I call it a Dolby MESS!