Dolby Atmos® creates powerful, moving audio by introducing two important concepts to cinema sound: audio objects and overhead speakers. Together, these completely change how soundtracks are created and heard.
Traditional surround soundtracks confine all sounds to a small set of channels that can deliver sound to you from only a few perceived angles. They cannot put sound above you. Further, sounds exist only as part of a channel mix. If one sound is emphasized in a traditional mix, another must be diminished.
In Dolby Atmos, by contrast, sound can be freed from channels. It enables artists to treat specific sounds as individual entities, called audio objects. These can be precisely placed and moved by the soundtrack creator anywhere in the cinema's three-dimensional space, though the artist can continue to use channel capabilities as desired. The Dolby Atmos cinema processor then determines which of a cinema's huge array of front, back, side, and overhead speakers it will use to recreate this lifelike movement.
As a result, a Dolby Atmos soundtrack brings alive the onscreen story as never before possible. The movie's sounds flow all around you to completely immerse you in the action, heightening the impact of the story and creating a powerfully moving cinema experience.
For information on installation requirements, check out the
Dolby-atmos-specifications.pdf
Dolby Cinema Solutions - Dolby Professional
Embrace our cinema solutions to improve the movie theater experience for your guests. Dolby offers audiovisual equipment, content management tools, and much more.
See all products
A more effective speaker setup
The most immediately noticeable difference in a Dolby Atmos® system is the use of overhead speakers, but that's just part of the story.
A typical surround sound system consists of left, center, and right discrete channels with the speakers behind the screen. The surround channels are handled by wall-mounted arrays of speakers, divided acoustically into two or four zones. All speakers within a zone receive the same audio information.
In a Dolby Atmos theater, every speaker — as many as 64 total — is powered independently and gets its own separate audio feed. In effect, each speaker is its own zone. In addition to the overhead speakers, Dolby Atmos typically adds more surround speakers and screen speakers.
The improved speaker layout is a key to implementing the dramatic audio improvements of Dolby Atmos.
Sounds gain their independence
Imagine sitting in a restaurant. There's a general buzz of conversation and music all around, yet you can pick out an individual voice behind you or a clink of silverware from the terrace above you — and you can tell exactly where each sound is coming from.
Now you're watching that same restaurant scene in a movie. With conventional surround sound, you'll get the ambience, but the voice and clink come from vague locations — if you can pick them out at all. That's because channel-based sounds — particularly surround effects —have to be assigned to a general zone, not a specific location. And because there are no overhead speakers, the sounds cannot move above you.
In Dolby Atmos, each of those sounds can be created as an independent entity — an audio object. Put all the objects together, and you'll feel like you're actually in the restaurant, not just watching a scene.
Any sound can be a single audio object, placed and moved independently anywhere in the theater. The filmmaker decides exactly where the sound should come from and where it should move. So you hear the roar of a plane flying overhead from above you, or a door closing to the left. Sounds can originate from a single speaker or sequence of speakers, or from any number of speakers simultaneously.
Audio objects empower filmmakers to focus on the story and put the sounds where they belong, rather than compromise the artistic impact to fit a fixed channel or zone.
Making the bed
Some elements of a movie soundtrack, however, still benefit from a channel-based approach — for instance, ambient effects and music backgrounds. So a Dolby Atmos soundtrack also includes a more conventional channel-based "bed," together with the audio objects. Dolby Atmos packages up to 128 audio tracks — a 9.1 bed and up to 118 audio objects.
Putting it together
The Dolby Atmos processor in the theater intelligently assigns each audio track. It maps the bed channels to screen channels or surround arrays, and positions objects within the room. It's all reproduced in real time based on where the loudspeakers are. Dolby Atmos scales to the specific speaker complement of a theater, so the effects will be the same regardless of the auditorium's size.
Sound placement is consistent throughout the audience. Thanks to audio objects originating from specific locations rather than general areas, you'll hear the exact same effect no matter where you sit in the theater — every seat is the "sweet spot."
Even more audio improvements
Having independently powered speakers improves the sound in other ways as well. For instance, tonal quality sometimes suffers when a sound is reproduced by an array of loudspeakers. Being able to direct that sound to single speakers makes the reproduction much more accurate and realistic.
Also, in traditional surround setups, a sound moved from the screen to the surround zones drops in volume. Dolby Atmos, using improved room equalization and better bass management along with the independently powered speakers, avoids this problem. Sounds maintain the right volume as they move, adding to the realism.
The complete Dolby Atmos system also includes authoring and distribution tools. For the full story in detail, check out our
white paper
.
Dolby Atmos represents a new era in movie distribution. This revolutionary new audio platform for the cinema greatly simplifies movie distribution by eliminating the need for multiple format inventories. With Dolby Atmos, the same file will play in any theater and faithfully reproduce the director's intent for the movie.
Dolby Atmos is a revolutionary new audio platform that gives you unprecedented and precise control over the placement and movement of sound within a movie theatre. You can tell your stories far more powerfully than ever before. Combining products, services, and technologies, Dolby Atmos represents a complete end-to-end audio platform for movies well into the future.