Back in 2000, when This is Spinal Tap was released on DVD with a new 5.1 mix, I grabbed a few words by email with Harry Shearer, who plays the not-quite fictional heavy metal band's hirsute bassist, Derek Smalls. Responding in character to the question whether HM should be presented in "Dubly" surround he answered that it should, of course, be in 11.1.
With the 30th anniversary of Tap's finest (or worst, depending on which way you look at it) moment coming up next year perhaps Smalls' wish will come true as immersive cinema sound systems are now a reality and becoming the next big selling point to get people back in front of the big screen.
The potential of surround sound for cinema was recognised as far back as the early 20th century and was realised by Disney in 1940 with Fantasound. Surround as we know it today appeared as Dolby Stereo in the mid-1970s and got a massive push from George Lucas' Star Wars in 1977.
This matrixed technology was superseded in 1991 by discrete 5.1, based on AC-3 coding, branded as Dolby Digital. DTS launched its 5.1 system in 1993, the same year an eight-channel system, Sony Dynamic Digital Sound (SDDS), appeared.
All these brought a new sensation to the cinema but the ultimate aim was to recreate as closely as possible how humans hear, reproducing height and depth as well as width and length.
In 2004 German company Iosono set out to create 3D sound using ‘wave field synthesis’. A different approach was taken soon after by Wilfried Van Baelen, co-founder of Galaxy Studios in Mol, Belgium. "In 2005," he says, "I came to a very logical conclusion: the closer to real life sound, the more immersive the impact. The art is to create that illusion of a natural sound experience with a minimum amount of speakers/channels and be fully backwards compatible with the 5.1."
The result was Auro-3D, a channel-based system with three vertical layers: lower layer, height layer and overhead/top layer. "The first thing to do is to create a natural spread of sound around the listener, horizontal and vertical," Van Baelen (pictured) explains. "The top/overhead layer is just good enough for some fly-overs and special effects but the key to the most immersive experience is the Height Layer. The combination of this with the Lower Layer creates a 'vertical stereo field', which is producing a much more life-like transparent sound around the listener."
Van Baelen formed a new company, Auro Technologies, to market his spatial sound system; Belgian manufacturer Barco, known for its digital projectors, has the exclusive film licence for the technology and markets it as Auro 11.1 by Barco.
"With Auro Technologies as a partner we can use our expertise in product design for cinema and translate the core technology to the specific requirements of exhibitors," says Tom Bert, product marketing manager for digital cinema at Barco. "Sound technology in cinema has been at a virtual standstill since the introduction of 5.1 and didn't keep up with the innovation that digital projection brought. We believe that in the near future we will see audio catching up and immersive systems being widely deployed." Imm-ediate success Spanish developer Imm Sound came to a similar conclusion in 2010 but instead of channels it worked with audio as a series of objects that can be moved and placed within a specified area. Prior to this Dolby saw competition in 5.1/7.1 for film dwindle: DTS sold its cinema business in 2008 and production of SDDS was discontinued.
Dolby Surround 7.1 became its flagship system for cinema but with new technologies emerging Dolby signalled a change in April 2012 with a new immersive technology, Atmos. This hybrid system keeps a 7.1 channel foundation but adds 119 additional objects that can be positioned anywhere in the aural picture. Three months later Dolby bought Imm Sound and integrated that technology into Atmos.
"We'd been doing experiments for a number of years, moving from the original base of 5.1 to 7.1 and then looking at the possibilities of 11.1 and 13.1," says Guy Hawley, senior director of international cinema sales for Dolby. "What became obvious by looking at the channel route is that we could only go so far. So we had to screw up the piece of paper, go back to the drawing board and think laterally."
Hawley says Atmos gives sound mixers a "broad canvas" to work on. To do it justice any final immersive mix needs large canvases in cinemas, which makes the number and type of loudspeaker in an auditorium more critical than ever. Hawley says Dolby is "brand agnostic", while Bert at Barco comments that the expectation is for exhibitors to choose its preferred loudspeaker and amplifier.
UK cinema installer Sound Associates is working on Dolby Atmos projects for two theatre operators; the Vue chain, which favours QSC loudspeakers, and the new, independent Olympic cinema in Barnes, west London, which is installing Flare Audio.
Sound Associates sales director Jerry Murdoch says that for new-build cinemas at least one immersive screen will be "the next big thing" to differentiate theatres from the competition. "In those circumstances its only a small uplift to the overall cost of the build," he observes. "But a retrofit can be quite expensive." Murdoch adds that the extra layers of surround "effectively doubles" the number of loudspeakers for those channels but says the real cost is in amplification because each speaker channel needs its own amplifier.
Both the Atmos and Dolby Surround 7.1 screens in the Olympic will feature Flare Audio X3-1515C tri-amped screen speakers for left, right and centre, plus the new SB21 flat-panel bass. The surrounds come from the newly released V8C Series.
"The immersive sound technologies by Dolby and Auro-Barco deliver the mix and quality of the soundtrack to the loudspeakers, placed to optimise the natural spatial sound experience for the audience," comments Kristin Hanson, chief operating officer of Flare Audio. "The quality of the sound produced by that channel is, however, limited to the quality of the loudspeaker that delivers the sound from the processor to the audience. The sound delivered by that channel should be highly defined and natural, allowing the audience to become truly absorbed in the moment." Into the Atmos-sphere Meyer Sound has produced a specific loudspeaker for this emerging market in the form of the HMS-12 high-power cabinet. Steve Shurtz, technology director of Meyer's cinema team, says the HMS-12 was first discussed two years ago in consultations held at Skywalker Sound: "It was specifically designed for systems like Atmos because we saw a requirement for more powerful speakers but ones that still looked like surround units."
Chuck Goodsell, senior manager for cinema at JBL Professional, says the screen channel speakers and subwoofers are no different in an immersive installation compared to 5.1 or 7.1 set-ups. "Surrounds are the primary change and in particular the overhead surrounds, of which there will be more," he comments.
@page_break@ JBL has expanded its AE Series to include specific overhead surrounds and these, along with other models in the range, feature in a number of Dolby Atmos installations.
Among these are five in the UK: the mix stages at Pinewood and Shepperton Studios, the Empire Leicester Square in London and two Dolby facilities: Screen 1 at the company's UK offices in Royal Wooton Bassett and the Ray Dolby Theatre (pictured) at its new Soho Square premises. Crown amplifiers and JBL loudspeakers, including AE Series AM7212s and AM7215s for overheads, were supplied through Sound Technology and installed by Bell Theatre Services.
Just as it seemed the nascent immersive cinema sound sector was going to be split between two systems, a proposed open format for object-based spatial audio might prevent a format war. Behind this is DTS, which, in July 2012, bought SRS Labs and its Multi-Dimensional Audio (MDA) object-based open platform.
At the CinemaCon show in April, DTS announced MDA as a non-proprietary format for object-based immersive sound, with the support of a number of companies, including Barco and Auro. The technology will be offered royalty free to companies to develop their own immersive systems.
John Kellogg, director for corporate strategy at DTS, says the company sees itself as a technology provider rather than a box builder. "We're now working with companies to use MDA as the basis of object-based systems that can be used by all manufacturers, including Auro-Barco," he says. He adds that MDA can be "anything people want it to be: channels, objects or hybrid".
DTS itself is developing new technologies for immersive sound based on MDA but says it is not getting back into the cinema sound business as before. Van Baelen comments that the Auro-3D suite of tools will support MDA object operation because it is vector-based and so can be used for other configurations as well as channels.
The Society of Motion Picture and Television Engineers (SMPTE) has formed a technology committee to look at cinema sound to update existing standards and recommended practices for consistent sound reproduction. Dolby supports and is involved in the SMPTE process and shows no sign of signing up to MDA. In a statement Dolby said: "We expect it will take a couple of years for the [SMPTE] standards process to produce a viable open standard. Dolby will continue to develop and promote Dolby Atmos as we believe it offers the best end-to-end system for customers looking for a solution today. Should a standard ultimately be adopted by the industry, Dolby will add appropriate support for it in our products. MDA, in contrast, has not been developed via the open standards process and is based on a proprietary format developed by DTS."
John Kellogg at DTS says SMPTE is "well aware of MDA" and refutes the claim that the technology is proprietary. It seems like cinema sound has moved on greatly in the number of channels and loudspeakers but not that far in old rivalries.
Story: Kevin Hilton