L-Acoustics, industry leaders in designing and manufacturing sound systems and technology, is helping to power the Timewalk experience at Immerse LDN, UK, where its L-ISA immersive technology envelops visitors in hyperreal sound.
The exhibition, which opened in July, takes audiences on an hour-long adventure through 12,000 years of human history. Visitors move from the ritual gathering grounds of Göbeklitepe to the hanging gardens of Babylon, the temples of ancient Egypt, the observatories of the Maya, and the Moai of Rapa Nui.
In total Timewalk runs 114 L-Acoustics loudspeakers and 11 subwoofers across five discrete zonesImage courtesy of L-Acoustics
Each of these five environments is housed in a dedicated projection-mapped room with discreetly installed sound that brings guests into the experience, but is invisible to the eye.
Installed by Asimetrik, an L-Acoustics certified provider in Turkey, the project builds on the provider's established collaboration with producer DEM Museums.
L-Acoustics solutions were specified following a rigorous selection process.
See also: Immerse LDN: London's new immersive entertainment hub
Delivering a technical advantage
Rather than identifying a system, the brief described an outcome: that visitors would not be aware of the equipment. Sound had to connect directly to an image, whether a bird overhead, water beneath the floor, or a voice moving across the space, and the experience had to be the same for everyone standing in the room.
Buğra Kezan, project engineering manager at Asimetrik, says: "Timewalk wanted an environment so cohesive that visitors wouldn’t be aware there were loudspeakers in the room.
"The sound had to be an integral part of the experience, and it had to work wherever people were standing and whichever room they were walking through."
Content was key to the exhibition's success, and audio would carry the same emotional weight as the visuals. Additionally, the system needed to run unattended, at the same quality, every day.
L-Acoustics L-ISA places sound genuinely above or beneath a visitor rather than only around themImage courtesy of L-Acoustics
As a result, each room has a bank of projectors that run continuously and create a consistent broadband noise floor through their cooling systems. This shaped the mix's dynamic range, keeping quiet passages clear above the background bed and limiting loud passages to maintain the intimacy of the storytelling.
Each of the five rooms also features independent content that runs simultaneously, all day, with no bleed as audience groups move between the spaces.
The architecture presented further challenges. Because Timewalk’s projection surfaces sit close to the walls, there was nowhere in front of them to mount a cabinet, so every enclosure had to be recessed into custom-built housing set into the wall.
The housings had to fulfil three functions that pull against one another. They could not colour the response or restrict the loudspeaker's directivity, or compromise isolation between rooms running independent material on separate cycles.
They also could not impinge on the fire escape corridors directly behind the walls, meaning that the available depth was fixed and non-negotiable.
Power was another hard limit. The building’s electrical infrastructure set the capacity, and the audio had to fit within it together with a significant projection load.
"That is where L-Acoustics separated itself from the alternatives they evaluated," says Kezan.
"The cabinet dimensions relative to the SPL we needed let the recessed housings stay within the depth the escape corridors allowed. And the combination of loudspeaker sensitivity and amplifier efficiency delivered the same acoustic result at a materially lower power draw.
"It was a technical advantage, not a preference."
Built as a permanent asset
Göbeklitepe, the first chapter, runs a 9.1 layout of three X8i, six 5XT and two SB15m.
The Babylon, Ancient Egypt and the Maya rooms each employ a full L-ISA 360 degree configuration with a layer of loudspeakers set into the floor, so sound can arrive from both below and around the guest. Five X8i, six X6i and 11 5XT are paralleled across three separate lines, with two SB18i apiece.
Rapa Nui, the final chapter, is the most demanding space and the only room to carry both a below-ear-level layer and an overhead one. This allows L-ISA to truly place sound above or below a guest, not merely around them. It runs five X8i, two A10i Wide, 29 X6i and three KS21i. Three additional 5XT cover the corridors between chapters.
In total, Timewalk runs 114 loudspeakers and 11 subwoofers across five discrete zones, powered by 15 amplified controllers including LA7.16i, LA4X and LA2Xi. All run on Milan- AVB.
The final mix is built in the L-ISA Processor, printed, and handed to the media servers, which send the files over the network directly to the amplified controllers.
The L-Acoustics sound system had to be an integral part of the experience, and it had to work wherever people were standing and whichever room they were walking throughImage courtesy of L-Acoustics
Sergey Becker, L-Acoustics application engineer, collaborated with the Asimetrik team through the final L-ISA calibration, while Pavel Aheunin, sales manager, provided support for the project from its initial stages to completion.
The immersive audio experience is meeting its brief. The producer’s content team immediately embraced the sonic result, and the exhibition’s own audio engineer rapidly picked up the day-to-day L-ISA workflow, an important consideration when each room needs to open to the same quality every morning.
"We specified this for the room, not for the content that happens to be in it," says Kezan.
"Immerse LDN rotates its experiences, and a new production can be authored against the loudspeaker layout and the object rendering that are already there, in most cases with nothing more than a recalibration and a new show file.
"The infrastructure is the permanent asset. The content sits on top of it."
Earlier this month, L-Acoustics announced that it has been awarded B Corp certification by the non-profit B Lab, joining just 70 companies in the arts and entertainment sector.
