The sound industry which is set to get a kick along with the release of new 24bit audio is also being helped by the release of new Dolby Atmos technology that can deliver sound to up to 34 speakers.
The new protocol which is fully backwards compatible with
older Blu-Ray players enhance a home theatre experience by deliver clearer
sharper sound to more speakers. A Dolby Atmos movie can be played back on
nearly any speaker configuration, from a 7.1 system all the way to 24 speakers
on the floor, and 10 as upper channel speakers.
Speakers can be added
in pairs by consumer’s after an inital base system has been installed.
Manufacturers who have announced Dolby Atmos AV receivers or
processors include Denon, Integra, Marantz, Onkyo, Pioneer, Steinway Lyngdorf,
and Yamaha.
The new technology won’t improve conventional mixes, so
cinemaphiles specializing in classic theatre, or for that matter, any title
recorded before the 2012 introduction of the technology, won’t see any benefit.
However, movies and other media recorded with Dolby Atmos will deliver a
significant improvement — adoption of the technology by content producers is
expected to be widespread by the end of 2015.
Electronista said that Dolby engineers believe that as home theatre
expanded to 9.1 and even 11.1 systems, problems of pursuing more and more
channels were aggravated. Home theatre content often originates from theatrical
content that is mixed in 7.1 sound as a best case and, many times, in 5.1. The
cinema-supplied mixes with fewer channels means that 9.1 or 11.1 systems
reached a point of diminishing returns in parsing and up mixing the limited
signal to serve more and more channels.
The company also notes the challenge with multi-channel
stereo in simulating reality. The example given by Dolby is the complex and
non-linear nature of a hummingbird’s flight captured on film. Moving the sound
from the left height channel to the right front channel loses details, and detracts
from the brain’s sense that what it’s watching is real.
Dolby Atmos is based on the concept each sound source being
a discrete “sound object.” In the cinema, Dolby Atmos relies on a
combination of 9.1 “bed” channels and up to 118 simultaneous sound
objects to deliver an enveloping sound scene. Each of those sounds comes from a
specific location in the scene, and can be in motion as well. The original
recording tracks both the source and the vector of motion, with the receiver
doing the locational sound translation during the decoding process.
Dolby has added extensions to existing Dolby TrueHD on
Blu-Ray and Dolby Digital Plus to support Atmos sound, making Blu-Ray players
and streaming devices compatible with the technology with little additional
investment, other than a compatible receiver.
A Blu-ray player that fully conforms to the Blu-ray
specification can play a Dolby Atmos movie without a firmware update.
Additionally HDMI 1.4 and later fully support Dolby Atmos. Dolby Atmos content
will be delivered through video on demand, broadcast, and cable services that
use multichannel Dolby Digital Plus in their core architecture.
Both Dolby TrueHD and Dolby Digital Plus with Atmos data are
backward compatible with older receivers and systems. If a movie mixed in Dolby
Atmos is played on a non-Dolby Atmos system, traditional 5.1 or 7.1 audio will
be played, depending on the type of system owned.
Dolby Atmos audio can also be encoded with Dolby TrueHD at
multiple sampling rates including 48 and 96 kHz, and 16- and 24-bit depths.
Dolby Atmos enabled receivers will also support legacy Dolby TrueHD bit streams
at multiple sampling rates including 48, 96, and 192 kHz and 16-, 20-, and
24-bit depths to provide full backward compatibility with legacy Blu-ray Disc
media and Dolby TrueHD music files.
For upper channels, Dolby has two solutions — either
integrated Dolby Atmos enabled speakers with an upward-firing speaker, or
Atmos-enabled add-on speaker modules which only include upward-firing speakers.
The speaker modules can be placed on top of existing speakers, or a nearby flat
surface.
Best results come from flat ceilings, made of an
acoustically reflective material like drywall, wood, or plaster. Dolby designed
the technology for rooms with ceiling heights of around nine feet, but ceilings
up to 14 feet still are nearly as good. Dolby claims that recessed lighting
fixtures, chandeliers, crown moulding, and heating or air conditioning vents in
your ceiling do not noticeably interfere with the sound quality from the upper
channels.
The technology for the home has been migrated from the film
production industry. The first feature film to use the technology was Pixar’s
Brave in July 2012. Since then, studios have released more than 100 films in
Dolby Atmos, including the entire series of The Hobbit, The Expendables 3,
Guardians of the Galaxy, Noah, Metallica through the Never, and Disney’s
Planes.
