Dolby Atmos: The Incredible Prototype Cinema Behind the Future of Movie Sound

By Chris Mills on at

Tucked in a corner of Soho Square, cosied up against ad agencies and seemingly every media firm in London, is the London HQ of Dolby, who you may remember from the title credits of just about every film ever. Hiding in the heart of this otherwise-ordinary building, though, is arguably the coolest cinema in the country, created at enormous expense to demonstrate the next gen of cinema tech.

The 68-seater Dolby Atmos cinema doesn't look like anything particularly special. Sure, the seats are a bit plusher than your average Odeon, but certainly nothing to write home about. The secret here is given away in the name -- Atmos. It refers to Dolby's headline technology, one that they reckon will leave mere 'surround sound' lying in the dust.


The Status Quo

All sound systems in existence use a number of audio 'channels', from one (mono) up to the current cinema surround-sound staple, 7.1 (meaning seven audio channels -- front left, front right, centre, side left, side right, rear left, rear right, and one whompwhompwhomp subwoofer), or even Super Hi-Vision's 22.1 channels. In general, the more channels you have, the better the 'soundstage' will be -- essentially, how directional the sound is. With stereo, you can tell if something's meant to be to your left or right; surround sound is leaps and bounds better, and should let you pinpoint that down to a healthy compass bearing.

Of course, this presents a problem for companies like Dolby, whose purpose in designing these sound systems is to make awesome movie soundtracks -- how do you get better? Sure, you could turn things up to 11.1, or so on, but this would surely suffer from the classic economist's problem of diminishing returns -- you'd plow in all that effort, only to see a tiny real-world difference.


Enter Atmos

Atmos is the much-hyped solution. Introduced in a packed Las Vegas theatre last year, it does away with the notion of speaker 'channels', and instead controls each and every speaker separately. Moreover, an Atmos-certified theatre has a greater range of surround speakers, including banks of the things installed in the roof.

This level allows sounds to be 'rendered in a 3D environment'. That means that rather than a sound coming roughly from the left or right, the sound will appear from an exact point in the cinema, in 3D -- a point that could be above, below, to the left or right of you. The effect is extraordinary, a level of realism so absurd and so detailed that it absolutely has to be heard to be believed. One of the Dolby demonstration tracks is a simple rainstorm. The depth of the sound is incredible -- the overhead speakers make it feel like it's genuinely raining overhead, and the precision of the Atmos systems makes it seemingly possible to identify individual raindrops with your eyes closed. Kat, who was sat next to me during the demo, actually commented that she felt physically chilled, such was the power behind the rain.

The other difference, from a technical standpoint, is that sounds are mapped out in a 3D environment. In the screenshot of the Atmos software above, each yellow ball represents a sound. Those balls aren't static -- as the sounds play, they'll bounce and move around, each following a pre-programmed 3D route that's painstakingly inputted with a joystick.

Obviously, Dolby's very keen to get this technology out in the public. Films are already being produced with Atmos sound -- Pixar's Oscar-winning Brave was the first -- but that sound is pointless if there aren't Atmos-capable cinemas to watch films in. That's a major problem for Dolby, because making cinemas Atmos-ready requires the aforementioned banks of speakers, racks of Dolby hardware in the projection room, and a significant amount of downtime while the whole thing's set up.

But that hasn't stopped Dolby (so far). Because Atmos is an impossibly difficult product to describe with words (as evidenced by the rambling paragraphs above), Dolby's built an Atmos demonstration cinema in its corporate HQ, bang in the centre of London. Outfit with gorgeously plush seats and 4K projection technology, not to mention that Dolby sound system, it's the perfect place to go all converting-missionary on the unbelievers. Building a cutting-edge cinema in the heart of a listed building isn't exactly the easiest undertaking, though.

With the emphasis firmly on sound quality, Dolby decided to create a cinema entirely isolated from the outside world. The floor is mounted on springs, which serves two purposes -- to isolate the Atmos from the low-pitched rumble of London's buses, and to stop the cinema's tonne of subwoofers literally shaking the building to bits.

Once the spring-laden floor was put in, attention turned to the walls. Just as a Thermos flask uses a dual-wall construction to keep its contents cool, the Atmos theatre has two walls, with a space in between to deaden the sound. The attention to detail continues with the doors, of which there are two, very thick ones.

The final touch is the roof. Once again, the designers sought a material that would deaden any outside noise. The normal candidates for acoustical muffling are dense fabrics like felt; stick those on a roof, however, and they'd get very soggy very quickly. The solution? A roof made of grass, which absorbs both water and sound with aplomb, while being eco-friendly to boot.

Inside, the cinema is specced out to the max. Despite the relatively small size, the Atmos has speakers running behind the screen, down both sides and the back, and three banks of the things in the roof. The speakers are full-range JBL units, which have a greater dynamic range than your average cinema speaker. At the back, racks of subwoofers provide the sort of bass that shakes fillings loose.

Once all the gear's installed, the cinema has to be calibrated, to map the sound from the software onto the right physical location. There's a Dolby programme that uses microphones and a fixed soundtrack to automate much of the process, but it still takes a team of technicians to fix it up. Although the installation is problematic for theatre owners, Atmos has one other advantage -- no more acoustical sweet spot.

All told, the Atmos experience is one you have to try yourself. Although the differences are subtle, they're certainly there, and given a few years -- the timeline Dolby's looking at -- it's easy to imagine Atmos becoming a staple of movie theatres, and even particularly glitzy home cinemas. Sadly, if you want to give Atmos a go right now, your options are pretty limited -- apart from Dolby's invite-only cinema, the only cinema in the UK with Atmos is the Empire in Leicester Square.