Dolby Atmos is an audio tech which D some have claimed is the biggest upgrade to surround sound in 20 years. It’s trickled down to the home from its beginnings in cinema screens, and literally adds a whole new dimension to living room sound by adding height channels to audio. Well, that’s one thing it does.
Dolby Atmos isn’t, in itself, sound — it’s a system of turning that audio into objects. Up to 128 individual elements in a scene are separated out into their own discrete tracks, each of which is given its own metadata which communicates to a Dolby Atmos–compatible receiver the way it should be handled. That metadata might include height channel or other positional information, or designate the track as a voice or background, but it doesn’t make explicit demands; it’s merely a way of communicating to compatible equipment.
It’s the end–user kit that does the real heavy lifting. A piece of Dolby Atmos hardware will typically know what it’s working with, be that a stereo setup or a full 7.2.4–channel speaker array, and will determine how to send the sound to the correct speakers based on that metadata.