Dolby Atmos - From The Cinema To Your Home Theater

Immerse yourself in a cocoon of sound with Dolby Atmos

Klipsch Dolby Atmos Speaker Setup
Klipsch Dolby Atmos Speaker Setup.

The Klipsch Group

Dolby Atmos is a surround sound format introduced by Dolby Labs in 2012 for use in Cinemas that provides up to 64-channels of surround sound by combining front, side, rear, back, and overhead speakers with a sophisticated audio processing algorithm that adds spatial information. The intent of Dolby Atmos is to provide a total sound immersion experience in a commercial cinema environment.

Following on the heels of initial success in cinemas (2012-2014), Dolby partnered up with several AV Receiver and speaker makers to bring Dolby Atmos experience into the home theater environment.

Of course, only the uber-rich can afford what it would take to install the same type of Dolby Atmos system that is used in the commercial environment, so Dolby Labs provided manufacturers with a physically scaled-down version that is more suitable (and affordable) to consumers in terms of making the needed upgrades to access the Dolby Atmos experience at home.

So, how can Dolby Atmos be effectively scaled down without losing its impact?

Dolby Atmos Basics

Pioneer VSX-933 Dolby Atmos Home Theater Receiver
Pioneer VSX-933 Dolby Atmos Home Theater Receiver. Pioneer Electronics  

With surround processing formats already found on many home theater receivers, such as Dolby Prologic IIz or Yamaha Presence, you can add a broader front sound stage, and Audyssey DSX can fill in the side sound field - but as sound moves from channel to channel and overhead - you can experience sound dips, gaps, and jumps (now the sound is here, now the sound is there) - in other words, as that helicopter flies around the room, Godzilla wreaks destruction, and, let's face it - rain and storms never sound quite right, the sound may appear wobbly rather than smooth as the filmmaker intended. In other words, you may not experience a continuous wrap-around sound field when there should be one. However, Dolby Atmos is designed to fill in those surround sound gaps.

Spatial Coding: The core of Dolby Atmos technology is Spatial Coding (not to be confused with MPEG Spatial Audio Coding) in which sound objects are assigned a place in space rather than to a specific channel or speaker. Upon playback, the metadata encoded within the bitstream included in content (such as a Blu-ray Disc movie) is decoded on the fly by the Dolby Atmos processing chip in a home theater receiver or AV processor, which makes the sound object spatial assignments based on the channel/setup of the playback equipment (referred to as playback renderer - such as the aforementioned home theater receiver or AV processor/amp).

Setup: To set up the best Dolby Atmos listening options for your home theater (provided you are using a Dolby Atmos-enabled Home Theater Receiver or AV Processor/Amp combination), the menu system will ask you the following questions: How many speakers do you have? What size are your Speakers? Where are your speakers located in the room?

EQ and Room Correction Systems: So far, Dolby Atmos is compatible with existing automatic speaker setup/EQ/Room Correction systems, such as Audyssey, MCACC, YPAO, etc...

Get High: Height channels are an integral part of the Dolby Atmos experience. To gain access to height channels, the user can install either speaker mounted in, or on the ceiling, or employ two new types of more convenient speaker setup and placement options.

One of these options is to add after-market speaker modules that rest on top of your current front left/right and/or surround speakers, or a speaker that can both front and vertically firing drivers encased within the same cabinet (refer to photo example).

The vertical driver directs sound that would normally be produced by ceiling mounted the speaker to the ceiling, which is then reflected back down to the listener. The demos I heard showed very little difference between this type of speaker design vs using separate ceiling mounted speakers.

However, it is also important to note that although the all-in-one "horizontal/vertical" speaker reduces the number of individual speaker cabinets, it does not reduce the amount of actual speaker wire clutter as the horizontal and vertical channel drivers have to be connected to separate speaker output channels coming from your receiver. The eventual solution to all the speaker connection complexities might just be self-powered wireless speakers, but this topic will possibly have to be addressed at a later date as no wireless Dolby Atmos-enabled speakers are available as of the most recent update to this article (information will be added when it becomes available).

New Speaker Configuration Nomenclature: Get familiar with a new way to describe speaker setup configurations. Instead of 5.1, 7.1, 9.1 etc... you will see descriptions such as 5.1.2, 7.1.2, 7.1.4, 9.1.4, etc... Speakers laid on in a horizontal plane (left/right front and surrounds) are the first number, the subwoofer is the second number (maybe .1 or .2), and the ceiling mounted or vertical drivers represent the last number (usually .2 or .4) - More details on this in the next section of this article.

Hardware and Content Availability: Dolby Atmos-encoded content on Blu-ray Disc is available (refer to our listing). Dolby Atmos is compatible with current Blu-ray and Ultra HD Blu-ray disc format specifications.

Dolby Atmos-encoded Blu-ray Discs are playback-backward compatible with almost all Blu-ray Disc players.

However, to access the Dolby Atmos soundtrack, the Blu-ray Disc player has to have HDMI ver 1.3 (or newer)  outputs, and the player's secondary audio output setting must be turned off (secondary audio is usually where things such as the director's commentary are accessed). Of course, a Dolby Atmos-enabled home theater receiver or AV processor must be used as part of the chain.

Dolby TrueHD and Dolby Digital Plus: Dolby Atmos metadata fits within the Dolby TrueHD and Dolby Digital Plus formats. So, if you cannot access the Dolby Atmos soundtrack, as long as your Blu-ray Disc player and home theater receiver are Dolby TrueHD/Dolby Digital Plus compatible, you still have access to a soundtrack in those formats, if they are included on the disc or content. What is also interesting to point out is that since Dolby Atmos can be embedded within a Dolby Digital Plus structure, implications are that you may see Dolby Atmos used in streaming and mobile audio applications.

Processing For Non-Dolby Atmos Content: To provide a Dolby Atmos-like experience on currently available 2.0, 5.1, and 7.1 content, a "Dolby Surround Upmixer", that borrows on the concept employed by the Dolby Pro-Logic audio processing family is included in most Dolby Atmos-equipped home theater receivers. In other words, in lieu of native Dolby Atmos-encoded content, you still have the availability to experience an approximation via the "Dolby Surround Upmixer". Look for this feature on Dolby Atmos-equipped home theater receivers.

Implications For The Consumer:  Moving beyond all the technical info, the big takeaway from my experience so far with Dolby Atmos is that it is a game changer for home theater audio.

Starting with sound recording and mixing, to the final listening experience, Dolby Atmos, although still requiring speakers and amplifiers to reproduce sound, none-the-less frees that sound from the current limitations of speakers and channels and surrounds the listener from all points and planes where sound can be placed.

From a bird or helicopter flying overhead, to rain falling from above, to thunder and lighting hitting from any direction, to reproducing the natural acoustics of exterior or interior environments, Dolby Atmos produces a highly accurate natural listening experience.

Dolby Atmos Speaker Placement Options

Dolby Atmos Speaker Setup Examples
Dolby Atmos Speaker Setup Examples - 5.1.2 and 5.1.4 - vertical and ceiling options. Onkyo/Dolby Labs  

There are four things you need to access the Dolby Atmos Experience, a Dolby Atmos-equipped home theater receiver (Dolby Atmos equipped receivers has to provide at least 7 channels or more of built-in amplification - see examples at the end of this article), A Blu-ray Disc player (most Blu-ray Disc players are already compatible), Dolby Atmos-encoded Blu-ray Disc content, and, of course, more speakers.

Oh No! Not More Speakers!

If home theater speaker configurations weren't already complicated enough, you might want to buy a large spool of speaker wire if you plan to the enter the World of Dolby Atmos. Just when you thought you could handle 5.1, 7.1, and even 9.1 - you may now have to get used to some new speaker configurations as shown in the above photo, such as 5.1.2, 5.1.4, 7.1.2, or 7.1.4.

So what the heck do the 5.1.2, 5.1.4, 7.1.2, or 7.1.4 designations actually mean?

The 5 and 7 represent how the speakers are normally configured around the room in a horizontal plane, the .1 represents the subwoofer (in some cases, the .1 might be .2 if you have two subwoofers), while the last number designation (in the examples provided - represent 2 or 4 ceiling speakers).

So what do you have to get to be able to accomplish this? A new (or, in select cases, upgraded) home theater receiver incorporating or adding Dolby Atmos Surround Sound decoding and processing capability, and, of course, more speakers!

Easy-to-Add Speaker Solution Possibilities

Dolby Atmos requires adding extra speakers, but Dolby and their manufacturing partners have come up with some solutions that may not mean you actually have to physically hang or place speakers inside your ceiling.

One solution that will be offered are small Dolby Atmos-compatible vertically firing speaker modules can be placed right on top of the front left/right and left/right surround speakers in your current layout - it doesn't get rid of the extra speaker wires, but it does make it more attractive than running speaker wire up your walls (or having to go into the walls).

Another option being offered are speakers designed to include both horizontally and vertically firing drivers within the same cabinet (practical if you are putting together a system from scratch or switching out your current speaker setup). This would also decrease the physical number of actual speaker cabinets needed, but just as with the module option, it doesn't necessarily cut down on the number of speaker wires you need.

What makes the speaker module or all-in-one horizontal/vertical speaker system work is that the vertically firing speaker drivers are designed to be highly directional, enabling them to project sound so that it bounces off of the ceiling before dispersing into the room. This creates an immersive sound field that appears to come from overhead. Average living and home theater rooms would have speaker-to-ceiling distances that should work, however, rooms with highly angled cathedral ceilings might be an issue and vertical sound projection and ceiling reflection would not be optimal to create the best overhead soundfield. For that scenario, strategy-placed ceiling speakers may be the only option.

More Info

You can get home theater receivers equipped with Dolby Atmos,priced from $400 to $1,299 and $1,300 and Up.

BONUS: Dolby Atmos Technical Documents