The term “Dolby Atmos” encompasses multiple speakers and Dolby’s immersive audio experience that enhances the creation and playback of music movie soundtracks and audiovisual content. These can be transmitted through various codecs like Dolby Digital Plus, Dolby TrueHD, AC-4.
Originally introduced in 2012 as a cinema playback system, it has expanded to the home theater sector and is now also available through streaming services like Netflix since 2017. The recent introduction of “Dolby Atmos” Music in late 2019 has marked its venture into the music streaming market.
For instance, Dolby Atmos tracks utilize the new AC-4 Immersive Stereo (AC-4 IMS) codec for headphone playback via music streaming services such as Tidal, and Dolby Digital Plus Joint Object Coding (DD+JOC) for speaker playback through platforms like Tidal or Amazon Music HD and now apple music.
Nevertheless, it’s important to note that the term “Dolby Atmos” is sometimes used as a quality certification. Not all “Dolby Atmos” files are necessarily based on multi-channel audio, and certain smartphones may even have a “Dolby Atmos” feature that enhances stereo sound. The outcome of such enhancements may vary based on personal preference, but Dolby has established a strong presence in the consumer market through this approach.
AC-4 codec
AC-4, a cutting-edge audio codec by Dolby Laboratories Inc., is standardized in ETSI TS 103 190 and ETSI TS 103 190-2. It takes the mantle from Dolby Digital (AC-3) and Dolby Digital Plus (EAC-3), introducing an evolution in multimedia entertainment services like streaming.
Specially developed for current and future immersive and personalized audio experiences, AC-4 supports NGA features. Its advanced loudness and DRC control cater to various device types and applications, while dialog enhancement, program IDs, flexible playback rendering, and other remarkable features further enhance the audio journey.
The AC-4 codec enables the transmission of channel-based and object-based audio content, combining them with excellent audio quality at low bit rates. With an average compression efficiency of 50% higher than Dolby Digital Plus, it sets a new standard and is not backward compatible with Dolby Digital or Dolby Digital Plus.
Substreams
AC-4 enables the transmission of various substreams within an audio data bitstream. These substreams can include different commentaries (mono), a 5.1 bed, or a 7.1.4 bed. The audio renderer can merge different substreams like a 5.1 bed with an English commentary or a 7.1.4 bed with a Spanish commentary. The decoder determines which “Presentations” are played based on the playback system in use.
Loudness
To ensure compatibility with various playback devices height speakers apple devices and systems, AC-4 incorporates flexible Dynamic Range Control (DRC) and loudness management. It defines four default DRC decoder modes: Home theater, flat-panel TV, portable speakers, mobile phones and headphones.
AC-4’s loudness management includes real-time adaptive loudness processing, where the encoder assesses the loudness of the incoming audio signal. It can then adjust the loudness metadata or employ multiband processing to achieve the desired loudness level.
Unlike encoding-based audio processing, AC-4 adds this information to the bitstream as DRC metadata, allowing the end device to handle the processing based on the playback scenario. This approach ensures non-destructive processing, preserving the original audio in the bitstream for future applications.
Dolby Digital Plus (DD+)
Dolby Digital Plus (DD+) builds on the existing AC-3 multi-channel standard, serving as an extension to Dolby Digital. DD+ is specifically mentioned in relation to DD+ JOC (as explained below), which remains the foundation often employed when leveraging “Dolby Atmos.”
DD+ was designed to augment AC-3 by enabling greater data rates (> 640 kbp/s) and accommodating a wider range of channel formats (beyond the maximum 5.1 supported by AC-3). Consequently, a flexible encoding system that remains AC-3 compatible was introduced, recognized as Dolby Digital Plus or Enhanced AC-3 (E-AC-3).
Dolby Digital Plus offers versatile capabilities, including support for up to 14 discrete channels in addition to the ability to transmit conventional mono, stereo, or 5.1 surround formats at a data rate approximately half that of Dolby Digital.
Joint Object Coding (JOC)
We initially developed JOC to offer a backward-compatible extension of the Dolby Digital Plus system. This extension enables the transmission of immersive “Dolby Atmos” content at bit rates, such as 384 kbp/s, commonly used in existing broadcast or streaming applications.
To ensure compatibility with existing Dolby Digital Plus decoders, we utilize a 5.1 (or 7.1) downmix within the DD+ JOC system. The decoding for DD+ JOC is already accessible via AVRs that support “Dolby Atmos” and other compatible devices.
We have also implemented an advanced tool called Advanced Joint Object Coding (A-JOC) in the AC-4 decoder. This tool includes adaptive downmix options and decorrelation units. Furthermore, the AC-4 A-JOC system supports all other features of the AC-4 codec.
Dolby Atmos
Dolby Atmos for cinema films
Originally introduced in 2012 for cinema playback, Dolby Atmos has since expanded, making its way into home cinema setups. Additionally, streaming services like Netflix started offering Dolby Atmos support in 2017. It’s worth noting that Dolby Atmos is more of a marketing term than a technical audio format definition.
What does Dolby Atmos Do?
Notably, Dolby Atmos Music entered the music streaming market in late 2019. Despite the rise of streaming platforms like Spotify, Tidal, Deezer, and Amazon Music, which have changed the accessibility of music, traditional channel-based production methods still dominate universal music group.
Dolby Atmos cinema processor, on the other hand, employs object-based technology for creating and playing immersive audio content. It relies on the AC-4 and Dolby Digital Plus (DD+) codecs.
What does “object-based” actually mean?
Object-based audio has gained prominence in recent years and is now making its way into the music streaming industry through technologies like Dolby Atmos for Music and 360 Reality Audio. Unlike channel-based audio, which stores and transmits speaker signals as the final production format, object-based audio describes the entire dolby and atmos soundtracks tracks and content using audio objects.
What are audio objects?
An audio object represents a virtual sound source with associated metadata, such as position and loudness. These objects can be positioned independently in the listening space, allowing for height information and overhead sound speakers.
Dynamic objects can change positions over time, while static objects remain fixed. Channel-based spatial audio, and the sound off the ceiling or speakers placed at specific positions can also be utilized and transmitted in object-based productions.
Playback possibilities of Music with Dolby Atmos
Within the realm of music streaming, 3D Music Dolby Atmos is accessible through Tidal HiFi (when paired with Dolby Atmos-enabled headphones or Amazon Echo speakers). Dolby actively partners with numerous music companies to bring this cutting-edge sound experience to life.
Consequently, previously released albums and tracks, available in stereo or 5.1 surround, will undergo reissues in the Dolby Atmos audio format, alongside fresh productions tailored for this immersive setting.
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FAQ Dolby Atmos
What does Dolby Atmos do?
Dolby Atmos enhances your audio experience by using sound and providing immersive 3D surround sound. It uses object-based audio to precisely position sounds in space, creating a more realistic sound and engaging audio environment.
How does Dolby Atmos work with conventional surround sound only?
“Dolby Atmos sound works by treating sounds as objects in space, breaking free from traditional channel-based audio. This allows sounds to move freely in three-dimensional space, offering a more dynamic and realistic audio experience.
Is sound better with Dolby Atmos?
Yes, Dolby Atmos provides clearer, more detailed, and crisper sound quality. It offers content creators in film, music, and gaming greater creative freedom to deliver their artistic vision, resulting in a superior audio experience.
What do you need to listen to Dolby Atmos music?
To enjoy Dolby Atmos, you’ll need an audio system that supports it. This includes Dolby Atmos-enabled soundbars wireless speakers, headphones, speaker systems, and AV receivers.
Can any speaker be used who support Dolby Atmos?
Most overhead speakers with wide dispersion characteristics can work in a Dolby Atmos home theater setup. Dolby Atmos uses discrete, full-range audio objects firing speakers that can move anywhere in three-dimensional space.
Does Dolby Atmos audio work with just a soundbar?
Not all soundbars surround channels support Dolby Atmos, but many 4K Blu-rays and streaming services like Netflix do. Soundbars surround speakers that offer Dolby Atmos support can provide a more natural listening experience.
How do you know if your speakers are Dolby Atmos?
You can check your TV’s settings or your AV receiver’s display for any mention of “Atmos” or “Dolby Atmos.” Additionally, Dolby Atmos-enabled speakers are designed to deliver your sound experience the full support of dolby atmos format specific audio experience.
Can you get Dolby Atmos through Bluetooth?
Dolby Atmos content is typically not delivered to single speakers through Bluetooth, AirPlay, or Chromecast. It requires an HDMI eARC connection between your sound bar like Sonos arc and TV for the best experience.
Which TVs have Dolby Atmos?
Various TV brands offer models that supports Dolby Atmos, such as TCL, Hisense, and more. Check the product specifications to ensure compatibility. Do smart TVs have Dolby Atmos? Many smart TVs support Dolby Atmos, providing an enhanced audio experience for your favorite content. Maybe even with Dolby Vision hdr for your favorite movie.
How many speakers do you need for Dolby Atmos?
While you can achieve a more immersive sound compelling experience with two Dolby Atmos-enabled speakers, it’s recommended to use four for more precise and realistic overhead sounds within the audio track.
How much does Dolby Atmos cost?
The cost of Dolby Atmos varies based on your chosen components. A complete Dolby Atmos setup can range from several hundred to a thousand euros, depending on your preferences. Ideally you add upward firing speakers or install height speakers for sound designers.
How do you turn on Dolby Atmos?
To enable Dolby Atmos, you need to configure your audio settings on your playback device, such as a TV or AV receiver, and ensure that you have Dolby Atmos content to enjoy the immersive, dolby atmos audio experience.
How does Atmos compare to surround sound?
Dolby Atmos represents a significant leap forward from traditional surround sound. While surround sound systems use channels to deliver audio, dolby Atmos system uses audio objects, allowing for precise placement and movement of sounds in three-dimensional space. This results in a more realistic and immersive audio experience, where sound can come from above, below, and all around you.
Is Atmos spatial audio?
Yes, Dolby Atmos is a form of spatial audio. It goes beyond traditional stereo or surround sound by accurately placing audio objects in a 3D space. This spatial audio accuracy makes the dolby Atmos sound tracks ideal for creating a sense of depth and immersion in audio experiences, whether in movies, music, or gaming that support atmos.
Dolby Atmos on mobile
Dolby Atmos has also found its way into mobile devices, enhancing the audio experience on smartphones and tablets. With dolby Atmos installation on your mobile device, you can enjoy immersive audio while streaming content or playing game consoles, all from the palm of your hand.
Dolby Cinema Solutions – Dolby Professional
Dolby Atmos titles extend its reach to the professional world, providing advanced audio solutions for filmmakers, content creators, and sound engineers or sound designer. Dolby Cinema Solutions offer tools and technologies that enable professionals to deliver the highest quality audio experiences for center dialogue in theaters and beyond.
Dolby Atmos Height Virtualization
For those who want to experience Dolby Atmos without the need for additional ceiling speakers, Dolby Atmos Height Virtualization comes to the rescue. It replicates the height dimension of Atmos audio, providing an immersive sound experience without the physical installation of overhead speakers and exact location.
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