Dolby Atmos has been around for a while now, with the sound technology gaining traction in Hollywood. But the majority of UK cinemas have still yet to equip their screens with compatible sound processors and speakers.
The good news is that you can now have the Atmos experience at home with the right equipment. Denon, KEF, Marantz, Onkyo, Pioneer and Yamaha all have Dolby Atmos-compatible products. LG has even announced all its 2017 OLED TVs will be the first ever televisions to support Dolby Atmos.
But, what exactly is it? And what do you need to get involved? Allow us to explain.
What is Dolby Atmos?
Dolby Atmos is a surround sound technology, developed in 2012, that expands upon the current 5.1 and 7.1 surround-sound set-ups with Dolby Atmos speakers placed at points all around the room. And we mean all around.
Speakers are placed along walls, in the ceiling and even behind the screen in order to push sound towards the audience. Up to 64 speakers can be used in a Dolby Atmos cinema, which is where the technology first appeared, and the idea is to totally envelop the audience in sound for a more immersive experience.
In a domestic environment it's unlikely you'll have room for 64 speakers, so there will be a number of simpler options: the addition of two or four ceiling speakers in your system; alternatively installing add-on speakers on top of your existing main floorstanding or bookshelf front left/right speakers (one set for a 0.2 configuration) or your left/right front and rear/surround speakers (two sets for a 0.4 configuration); or the purchase of a purpose-built Atmos speaker system.
When a Dolby Atmos system is installed, the room receives a complete calibration which allows sound mixers to ‘place’ sounds and voices at exact points in the room. Each speaker in an Atmos system has its own feed, enabling new front, surround and ceiling-mounted height channels.
Dolby Atmos in the home
Given that a full, cinema-style installation isn't a practical solution for most people, with a large number of speakers installed around the room, a simpler solution is required. That’s where the AV manufacturers come in to play.
The first thing you'll need is a compatible AV receiver to decode the Atmos soundtrack from a Blu-ray disc. All our 2016 Award-winners are compatible with the format which now tends to be supported in most new models, from budget all the way up to premium.
The good news is you don't have to go and install in-ceiling speakers. Dolby’s hardware partners will also produce side speakers that aim to do a similar job of delivering an enveloping sound without needing speakers attached to your ceiling.
Pioneer is one of the first to market with a complete Atmos speaker package: the S-73A. While the package does a great job of creating the Atmos surround sound, with effects whizzing above your head, the overall sound could be more detailed.
It's a move in the right direction, although dedicated Atmos speaker packages are still in relatively short supply.
Atmos can also work with existing home cinema systems. Dolby Atmos-enabled speaker modules are available, which, when placed on top of your speakers, will allow your system to deliver Dolby Atmos sound from a compatible AV receiver.
KEF is one such brand, with its R50 speaker module. The module isn't limited to being used with KEF speakers - it can be placed on top of any speakers you already own.
Dolby Atmos tech is also available in a number of different soundbars - they tend to use up-firing drivers to disperse sound overhead. The Yamaha YSP-5600 and Samsung HW-K850 are two models we've reviewed, while new models recently announced include the SJ9 from LG and Sony's HT-ST5000.
More after the break
Dolby Atmos films
Plenty of films have now been produced in Dolby Atmos, the first of which was Disney Pixar’s Brave back in 2012. Other films including Pacific Rim, Noah and Gravity.
Plenty of directors have said nice things about Atmos, too. Guillermo Del Toro said: "With Atmos, I found creatively a complete game changer.
"I think that everybody talks about 3D imaging, and Atmos is 3D sound... I truly embrace Atmos, I think that every theatre should embrace it and it’s my preferred method for mixing sound, in the world right now."
While Peter Jackson, also a fan of 3D film, said: "Dolby Atmos provides the completely immersive sound experience that filmmakers like myself have long dreamed about."
There are currently over 40 cinemas in the UK and Ireland that are fitted with Dolby Atmos technology, including the Empire Leicester Square in London and the Showcase in Leeds. You can see a full list of Dolby Atmos cinemas on the Dolby website.
The majority of DVD, Blu-ray, HD TV and other surround sound audio sources offer a 5.1-channel soundtrack.
This means if you have a 7.1 (or more) speaker configuration, your AVR is sending the 5.1 signal to your extra speakers.
With Dolby Atmos, there is one mix for all speaker configurations. This takes into account whether you have ceiling speakers or Atmos-enabled front speakers or add-on speaker modules – and will hopefully be matched by content with Atmos surround sound mixes.
A 5.1.2 set-up will be a traditional 5.1 setup with either a pair of ceiling speakers or a pair of Atmos-enabled speakers, which are the '2' in 5.1.2. Meanwhile, a 7.1.4 set-up will be a 7.1 setup with either two pairs of ceiling speakers or a pair of Atmos-enabled front speakers and a pair of Atmos-enabled surrounds.
Atmos AV amps will do their best to get more from traditional surround sound set-ups and 5.1 soundtracks.
Dolby Atmos content
So, you’ve got your compatible kit to get Dolby Atmos in your home, now all you need is some content to play and revel in the full-room sound experience.
Dolby says you shouldn't need a new Blu-ray player to support Dolby Atmos as long as you have a player that fully conforms to the current Blu-ray specification. And crucially, compatible Dolby Atmos movies are available in both Blu-ray disc and streaming formats.
The first film to come with a Dolby Atmos soundtrack on Blu-ray was Transformers: Age of Extinction, in November 2014. Since then, a fair few Atmos-compatible films have been released in the UK - check out the full list on Dolby's website.
Away from films, Sky and BT are also showing Dolby Atmos some love. BT now broadcasts every Premier League match on its BT Sport Ultra HD channel with Dolby Atmos. While Sky Q doesn't support Atmos at the moment, it did reveal in its recent financial results that it's on the road map.
Dolby Atmos on the go
Dolby Atmos works on tablets like the Amazon Kindle Fire HDX 8.9 via connected headphones. Though it won't be quite as immersive as with a soundbar or a surround sound system.
Atmos on a tablet works through 'binaural headphone rendering' and 'object-based audio". Binaural headphone rendering creates surround sound through headphones via heat-related transfer functions (HRTFs). To explain how this works, Dolby gives an example of a car honking its horn. If it honks to your right, your right ear gets the full blast, while the left ear gets a less intense sound because the sound has to travel around your head. The brain recognises the differences, telling you to look to your right to see if the car is near you.
Dolby has reversed this process to create virtual surround sound from the single speakers in headphones, producing the effect that sound is coming from all around you.
'Object-based audio' is the foundation of Dolby Atmos. Each sound in a scene has information that explains where it should be placed in the speaker configuration and Dolby claims to have these two technologies together to create a virtual, enveloping surround sound experience on a mobile platform.