Dolby Atmos

Dolby Atmos is the name of a surround sound technology announced by Dolby Laboratories in April 2012 and released in June of the same year, first utilized in Pixar's Brave.

The first installation was in the Dolby Theater in Hollywood, California, for the premiere of Brave in June 2012. Throughout 2012, it saw a limited release of about 25 installations worldwide, with an increase to 300 locations in 2013. There were over 2,100 locations as of February 2015. Dolby Atmos has also been adapted to a home theater format and is the audio component of Dolby Cinema.

Dolby Atmos technology allows up to 128 audio tracks plus associated spatial audio description metadata (most notably, location or pan automation data) to be distributed to theaters for optimal, dynamic rendering to loudspeakers based on the theater capabilities. Each audio track can be assigned to an audio channel, the traditional format for distribution, or to an audio "object." Audio tracks that are assigned to channels, such as ambient sounds or center dialogues, are pre-mixed to a "7.1.4" multichannel format: Dolby Atmos home theaters can be built upon traditional 5.1 and 7.1 layouts. For Dolby Atmos, the nomenclature differs slightly: a 7.1.4 Dolby Atmos system is a traditional 7.1 layout with four overhead or Dolby Atmos enabled speakers.

With audio objects, Dolby Atmos enables the re-recording mixer using a Pro Tools plugin (available from Dolby) or a Dolby Atmos equipped large format audio mixing console such as AMS Neve's DFC or Harrison's MPC5, to designate the apparent source location in the theater for each sound, as a three-dimensional rectangular coordinate relative to the defined audio channel locations and theater boundaries.

During playback, each theater's Dolby Atmos system renders the audio objects in real-time such that each sound is coming from its designated spot with respect to the loudspeakers present in the target theater. By way of contrast, traditional multichannel technology essentially burns all the source audio tracks into a fixed number of channels during post-production. This has traditionally forced the re-recording mixer to make assumptions about the playback environment that may not apply very well to a particular theater. The addition of audio objects allow the mixer to be more creative, to bring more sounds off the screen, and be confident of the results.

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