First Listen: Dolby Atmos Is "Right" At Home

The Dolby Atmos surround-sound format for home theaters made its debut this week with product announcements from several manufacturers and live demos in New York City at the Consumer Electronics Association's CE Week trade show. The technology that Dolby first introduced to theaters in 2012 offers the potential for a far more immersive audio experience than the traditional 5.1- and 7.1-channel systems that are still mostly employed today, and having experienced Atmos in the cinema, I admit I was pretty pumped heading into the demos.

And I wasn't let down. Atmos in the home environment seems to work—surprisingly well, in fact. Caveats? Yeah, there are a few worth watching out for that I'll get to later. But overall, I'll go on record that this is probably the most discernable advance in home theater sound since the introduction of lossless digital audio in the Dolby TrueHD and DTS-HD Master Audio formats on Blu-ray. And it's one that leaves all the pre-existing height- and width-channel surround formats— including Dolby Pro Logic IIz and DTS Neo:X—in the dust. Finally, this may be one that will truly make it worth the trouble of adding those extra speakers. Maybe...

What is Atmos?
If you've not been exposed to Atmos or don't know what it is, don't feel bad. The system only debuted with the release of the Disney film Brave in 2012, and Dolby currently lists only about 130 or so theaters in the continental U.S. on its Atmos locator. They tend to be mostly in high-population regions, and even where Atmos theaters exist, the exhibitors haven't always done a great job of promoting them. At the AMC theaters that feature it, for example, it's lumped in as one of the technologies being offered in some of their ETX (Enhanced Theater Experience) auditoriums; if you look for the word "Atmos" in their movie listings, you won't find it.

For those unfamiliar, Atmos is an object-based audio mixing system that allows movie sound engineers to place objects essentially anywhere inside of a dome-shaped envelope above the audience. Recorded "objects"—whether a human voice reciting dialog, the sound of a traveling helicopter prop, an insect in a tree in the forest, or a foley effect of breaking glass—are dropped inside a graphic representation of the listening space displayed on a desktop monitor, moved around as desired, and assigned metadata that describes the object and its position at any given moment. This data becomes a permanent part of the soundtrack. The Atmos decoder in the theater knows the speaker/channel configuration available to it at that installation; as many as 64 separate speaker channels can be addressed by the processor. When the soundtrack is played back, it uses the metadata to automatically map the speaker output levels in real time to position each sound as close as possible to where the mixing engineer intended.

This is already decidedly different than traditional "channel-based" mixing, wherein a movie might be mixed with a 7.1-channel soundtrack in which every sound gets manually placed, or panned across different channels on the mixing board to create a sense of movement. The 7.1-channel soundtrack must then be arduously adapted to 5.1-channel and stereo mixes for smaller systems. That work is essentially eliminated with Atmos. But what's key to the Atmos theatrical experience is the addition of individually addressable ceiling speakers, typically found in left/right pairs that correspond to the position of the surround speakers mounted on the theater's side walls. It's the ceiling speakers, and the way in which they're discretely controlled by the Atmos soundtrack, that allow for a more realistic soundfield than has been possible even with a traditional 7.1-channel setup with side-wall and back-wall surrounds, or any of those artificially-derived adaptations that add height and width speakers to 7.1 and 5.1 channel soundtracks. Instead of ambient sounds tending to hug the boundaries of the room where the surround speakers have been traditionally located, they can be made to come from directly overhead for any seat in the audience.

All of that said, my impressions of Atmos in the theater have been largely dependent on how the film's creators chose to use the available tools. The effect can be subtle and simply create a more convincing ambience for special effects, as was done in the Hobbit films. Or, it can be more pronounced, as in Life of Pi. While Pi made superb use of the overhead speakers to recreate the feel of wild ocean storms, the soundtrack also used the ceiling speakers at times to place elements of the music score overhead while the rest of the score played across the front speaker array, allowing for a greatly expanded and spacious soundstage. With either approach, though, you're going to come away with a fresh and more engaging movie experience.

Atmos At Home
About 200 movies have now been mixed in Atmos. Making use of those soundtracks in home theaters means adding what most often would be four additional speakers to convey the the ceiling-speaker information. You need a source component that can deliver an Atmos bitstream, an AVR that can decode the bitstream and drive power to the extra speakers, and the speakers themselves.

For soundtrack delivery, Dolby says any existing Blu-ray player should suffice, and I noticed the demo discs being used for the CE Week demos offered Atmos menu options for both Dolby TrueHD and Dolby Digital Plus soundtracks; the latter could potentially be used for streaming content. For the decoding hardware, Atmos firmware upgrades for pre-announced AVRs or brand new Atmos-enabled AVRs are planned by several manufacturers, including Onkyo and sister brand Integra, Denon and sister brand Marantz, Pioneer and Yamaha. Higher-end 9.1-channel models are an obvious fit because they provide the amplifier power to drive four additional speakers in what Dolby is designating a "5.1.4-channel" system to include the traditional five surround channels, the subwoofer, and four ceiling speakers.

More Dolby Atmos News:
Dolby Atmos Movie-Theater-Sound Technology Heading to Home Gear

Pioneer Showcases Dolby Atmos-Enabled Receivers and Speakers

COMMENTS
David Vaughn's picture
Rob, Thanks for the great recap on the systems that are forthcoming. My main listening room can be set up for Atmos pretty easily, but I have a cathedral ceiling and I'm not sure what the effect will be like in that kind of room. Furthermore, do the speakers need to be timbre matched to your main speakers? Lots of questions will surely arise the next few months, but I like this much better than the current options that are out there with height and width speakers, which in the demos I've been apart of have been very underwhelming.
dnoonie's picture

Thanks for the overview! I'll trying Atmos when I get a chance.

I tend to get fewer and higher quality components, I don't see spending $2000 to $3000 per pair as being really affordable nor adding that much to the experience. I'm already pleased with my 5.1 experience, my theater room is rather small for additional channels, I have ceiling absorption treatment to prevent ceiling reflections from mains and surrounds and can't imagine removing them would enhance the sound since I experienced improvements when adding them. Gimmick or not, I'll be willing to try a demo when a good one gets installed at my local Magnolia, or elsewhere...I just called Magnolia in Seattle and they currently have no plans for an Atmos demo room, that's not that they won't it's just not yet in they're plans yet.

I checked with my local Regal and they have an Atmos equipped theater but it's a price premium and not all movies in it are Atmos and there are no designations on the theater listings to indicate that the movie showing in that theater is Atmos. If they make it this difficult to try I don't see how it's going to catch on.

Thanks again. I don't mean to sound negative I'd like to try Atmos but I'm having trouble doing so.

Cheers!

Rob Sabin's picture
Thanks for the comments, guys. You bring up some good points. First, will this work in rooms with different ceiling heights and designs, such as cathedral, coffered, etc.? I believe I remember a company rep at the demos saying that Dolby expects a ceiling of 14 feet or less (don't hold me to that without confirmation), but it worked fine in one of those rooms at a 15 foot height and I was told by someone else anecdotally that they'd heard it work effectively in a room with an 18 foot ceiling. That said, can the reflective speaker approach coexist in rooms with a treated ceiling? Best practice for home theaters ideally dictates absorptive materials on the ceiling at the point of first reflections off the front speakers, and I've been in plenty of basement theaters that had sound absorptive tiles in a dropped ceiling. Another reason, perhaps, that a true ceiling speaker installation may be a better, more fool-proof approach. On the other hand, unlike in the cinema where the ceiling height is quite high and the room quite cavernous, will downfiring ceiling speakers in a traditional home theater be too close and perhaps more localizable? Logic suggests that a in-ceiling surround speaker that spreads the sound around might work best, but I'd love to hear Dolby's recommendation on whether a dipole, bipole, or traditional ceiling speaker offers the best option.

Regarding the need for timbre-matching the ceiling channels, the answer is probably no. The fact that Dolby spec'd a full range driver as acceptable for the reflective-type ceiling speakers suggests it's not completely critical to have a perfect match with your other multi-driver speakers. In my informal chat with Andrew Jones at Pioneer, he also suggested that timbre matching was not the critical factor in his decision to execute an Atmos speaker with a matching coaxial driver. Rather, he said, (and if I understood him correctly) the preservation of certain phase relationships with the other drivers and therefore certain spatial characteristics of the sonic envelope was what drove that decision. Short of a direct comparison in the same room with the same content, we'd be really hard-pressed to know what difference it makes.

prerich45's picture

Excellent points made, both by you and the article author. In another thread - I wasn't trying to execute Atmos, but I know it's not for everyone.

bkeeler10's picture

Dolby or another manufacturer may say that timbre-matching is not critical, but I bet such a statement would be at least partially driven by the desire to not scare anyone away from buying into Atmos. Regardless of what Dolby or anyone else says, it seems to be a good idea to have all your speakers in a system timbre-matched as much as possible. If the content in the height channels is potentially full-bandwidth, and if it will at times involve panning from the fronts to the heights to the backs, timbre-matching is at least as important as it would be for your traditional surrounds.

I personally would not implement an Atmos system at home that compromises the seamless sound quality I have with my traditional system. That just doesn't make sense to me. So, for any such system I would set up, it would be actual on-ceiling speakers (not sound reflected off the ceiling) and it would be all speakers from the same manufacturer and line for the best possible match, with additional EQ as necessary to deal with the issues created by having speakers against a room boundary.

William Lee's picture

According to The Nielsen Company, over 85% of Blu Ray are encoded in DTS HD Master. Unless the movie studios are switching, (think high switching cost), to Dolby True HD with Atmos encoded Blu Ray, there will be very few contents available. Of course, Dolby can add a "simulated" Atmos like all the other useless surround modes to the receiver so that the receiver can still be using the ceiling speakers regardless of audio encoding.
I love the Dolby's idea, but DTS will most likely come up with something similar to keep the movie studios from switching. DTS will probably sell s software upgrade to movie studio to make it work, (think low switching cost).

Rob Sabin's picture
SRS had released its own object-based filmsound mastering system just prior to its purchase by DTS and was working to get studios to use it on their movie projects. Dolby swooped in with Atmos and apparently stole their thunder, and I'm not sure how successful it's been. Bottom line: for this to be effective, you ideally want content that's been discretely mixed for it.
Thomas J. Norton's picture
I hope the Atmos Blu-ray discs that are released, such as they might be, will continue to use lossless Dolby True HD for ALL of the channels. Anything less would be a step backward.

Incidentally, the AMC, Atmos-equipped ETX theater near me has dropped the ETX designation and now calls itself Prime. The latter has added reclining seats and seat shakers (fortunately the latter are not turned up to 11), and is still Atmos-equipped. One irony, however, is that when The Hobbit (the first one) came out in high frame rate, it played in both the (pre-Prime conversion) ETX house and the adjoining IMAX auditorium. But the high frame rate was only playing in the latter, and Atmos only in the former. So you had to choose between high frame rate and conventional multichannel sound or Atmos with the standard frame rate. Of course, this was near LA. Readers in more conventionally equipped areas, perhaps with no IMAX, ETX (or Prime), high frame rate, or Atmos capability are mumbling "Poor Baby!" :-) I feel your pain, since I may soon be moving to an area no nearly so well endowed.

danrudy's picture

Great.
After agonizing for the last month I was ready to buy a AVR and a surround speaker system for my brand new HT. I was settling between Triad, SVS and ascend and Denon 4000
THen I heard about the Atmos....
Now what? The AVR and speakers were the last component needed to finish off the theater,,,If I am going to purchase something now, I sure would like it to utilize Atmos technology if feasible.
ANy suggestions on how to proceed....I was really looking to get the sound purchased this week...sheesh!..LOL

Rob Sabin's picture
At this point, all the major AVR manufacs have announced plans to either firmware update existing models later in the year to make them Atmos compliant or release new models that will feature Atmos. If you opt for a unit that is in the market now but slugged for update you'll be covered on the electronics for later, though the need to drive the extra speakers would suggest moving to at least a 9-channel model with amplifiers for 4 additional speakers; some 7-channel models will also be available to add just a pair of ceiling channels on top of a 5.1 setup, but it remains to be seen how effective this will be. Likewise, it also remains to be seen whether using the combined front-firing/ceiling speakers will be the best solution vs. in-ceiling speakers. It's all very early.

As for speakers...Triad appears to be one of the brands making Atmos-enabled speakers with ceiling-channel drivers based on their use in Onkyo's demo at CE Week, but you'd have to check with them on when these will actually come to market. If you're covered on the electronics with your receiver choice, one possible option might be to just plan on installing in-ceiling speakers now or running wires to install them later, and then go ahead and buy the speaker system that sounds best to you now for music and all of your non-Atmos movie content, which is the vast majority of what you'll be watching. I'd be very hesitant to restrict my speaker choices now based on this announcement. We just can't advise anyone right now with so many product announcements yet to be made and with no real experience with the system and the different configurations.

stodgers's picture

I'd be interested to know which 200 titles are now Atmos (does Dolby have this listed?), because seeing The Hobbit in it was a revelation. Though the film itself wasn't very notable, the HFR and Atmos made it a completely immersive experience unlike anything else I've experienced. So while I'm not slated for an upgrade anytime soon, this might give me a reason to rethink that.

Bob Ankosko's picture
Click here for a list of movies with Dolby Atmos soundtracks.
HMB's picture

Will dipole side channels work with Atmos? Mine are above ear level(by 2 feet) - should I use them for the back ceiling speakers? Can our receivers compensate for their position? What about a center speaker that is ABOVE the tv _ can't be mounted below in my setup. All these issues, if not addressed, will prevent the consumer from being in to Atmos.
I just downloaded a Denon manual for the top-of-the-line Atmos receiver, and their setup information is SAD. Not a good start.

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