[epm]

Unfortunately, as far as I know, there's not really a simple, budget friendly way to do what you want.

The AT-300 will take an atmos (or any) stream from a consumer device and output it analog to your speakers. However, there's no way that i know of to get the multichannel 7.1.4 out of DAPS into the AT-300, I don't think you can get more than 8 channels of PCM audio over HDMI out of Pro Tools, and i've never been able to get more than 2. So you'd need a totally separate monitoring path to listen to atmos, which negates the benefits of having the room calibration and volume control all built into the AT-300.

You'd need either a home theater processor that would take a straight analog in speaker to speaker passthrough, or a way to encode an atmos stream over HDMI in realtime (which there isn't any). Otherwise the setup would need at minimum an audio interface with enough analog outputs to drive your atmos system, and enough analog inputs to take signal from the home theater processor and pass through to your speakers for the consumer playback.

edit: I Would love to be proven wrong, cause i'd love to have this type of setup at home too!