FREQUENTLY ASKED QUESTIONS ABOUT DOLBY ATMOS® FOR
THE HOME
August 2014
Q: What is Dolby Atmos?
Dolby Atmos® is a revolutionary new audio technology that transports you into extraordinary
entertainment experiences.
Fills your room with captivating sound
Puts sounds into motion all around you
Delivers the full impact of the artist’s work
Moves your mind, body, and soul
o Sound comes from all directions, including overhead, to fill the room with
astonishing clarity, richness, detail, and depth.
o The specific sounds of people, music, and things move all around you in
multidimensional space, so you feel like you are inside the action.
o Artists have amazing new capabilities to tell their stories, accent their games, or
perform their music to achieve the greatest expressive impact.
o Sound excites your senses and inspires your emotions, flowing around you and
connecting with you to create a more profoundly moving experience.
Q: How does Dolby Atmos audio work?
Until now, cinema sound designers have had to mix independent sounds together into channels
for soundtrack creation. A discrete sound, such as a helicopter, has been assigned to an
individual channel rather than precisely to where it would occur naturally in the scene. While a
sound can move across channels, there’s no height dimension. For example, you might hear the
helicopter from a side channel and not above you. This approach limits your audio experience
because it can’t come close to matching the way you hear in real life, with sounds coming from
every direction.
Dolby Atmos is the first home theater system that is based not on channels, but on audio
objects. What is an audio object? Any sound heard in a movie scene—a child yelling, a helicopter
taking off, a car horn blaring—is an audio object. Filmmakers using Dolby Atmos can decide
exactly where those sounds should originate and precisely where they move as the scene
develops.
Thinking about sound in this way eliminates many of the limitations of channel-based audio. In a
channel-based system, filmmakers have to think about the speaker setup: Should this sound
come from the left rear surrounds or the left side surrounds? With Dolby Atmos, filmmakers just
have to think about the story: Where is that yelling child going to run? How will the helicopter
move overhead after takeoff? The Dolby Atmos system, whether in the cinema or a home
theater, has the intelligence to determine what speakers to use to precisely recreate the child’s
movement in the way the filmmakers intend. They can now precisely place and move sounds as
independent objects in multidimensional space, including anywhere overhead, so you can hear
them as you would naturally.
A Dolby Atmos home theater is also far more flexible and adaptable than channel-based home
theater. In a channel-based system with channel-based content, the number of playback
speakers is fixed: a 7.1 system consisting of seven speakers and one subwoofer is used to play
7.1 content. Additionally, there is no height information in the content. With Dolby Atmos, in
contrast, you have amazing flexibility: the format provides even richer, more detailed sound by
rendering to overhead or height speakers and/or to more than seven speakers at the listener
level. As you add speakers, a Dolby Atmos enabled receiver will use them to create even more
fantastic, immersive audio.
With the revolution in audio that is Dolby Atmos, sound designers are freed from channel
restrictions. Sounds flow above and around you in step with the visuals, bringing a new sense of
height and reality to your listening experience. Dolby Atmos helps weave the audio story to
match what’s happening on the screen. It puts you in the middle of the action—in ways you
have never experienced before.
Q: What is the difference between Dolby Atmos in the cinema and Dolby Atmos
in the home?
The cinema, with its giant screen and massive sound system, will always be the reference for
the ultimate entertainment experience. While home theaters have fewer speakers, the Dolby
Atmos home experience is extremely powerful. It combines traditional home theater speaker
layouts with many new possible speaker positions, including either ceiling-mounted speakers or
new Dolby Atmos enabled speakers that reproduce sounds coming from above you. The impact
of either in-ceiling or Dolby Atmos enabled speakers is breathtaking; your room fills with realistic,
multidimensional sound that places you directly in the center of the entertainment experience.
Q: How does Dolby Atmos cinema content transition to home theaters?
The Dolby Atmos experience in the cinema is so powerful and flexible because of its
revolutionary use of audio objects. To deliver the full object-based soundtrack to home theaters,
Dolby developed new home authoring tools and new encoding methods that take into account
the spatial information of the sound objects to efficiently encode them in Dolby® TrueHD and
Dolby Digital Plus™. This spatial coding is not a channel-based, matrix-encoding system like
Dolby Pro Logic® II or Dolby Pro Logic IIz. Instead, this fundamentally new coding technique
allows all the audio objects created for the cinema to be used in the home theater. Nothing is
lost.
Initially, home theaters will be able to play Dolby Atmos content on Blu-ray™ discs or through
streaming video services. No matter the source, when a Dolby Atmos stream is fed to a Dolby
Atmos compatible A/V receiver, the receiver will render the object-based audio to your home
theater’s unique speaker configuration to precisely recreate the sound the filmmakers intended.
Because the object-based audio mix is delivered to home theaters, Dolby Atmos has the ability
to adapt to extremely diverse speaker setups, from systems with five speakers on the floor and
two speakers producing overhead sound to Dolby Atmos supersystems with 24 speakers on the
floor and 10 overhead speakers.
Q: Who is creating content, such as movies, for Dolby Atmos in the home?
Globally, more than 100 cinema blockbusters have been released featuring Dolby Atmos
soundtracks since 2012, and many more are on the way. Major Hollywood studios are partnering
with Dolby to create home video versions of current box office releases—and previously released
favorites—for release in 2014. In addition to global studio partnerships, Dolby is partnering with
game and music content creators to take advantage of Dolby Atmos technology for future home
theater use.