20.1 Cinema Audio Solution Coming from Barco

By Chris Chinnock Don't Use
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Digital Cinema – Barco (Kortrijk, Belgium) announced that it has completed the acquisition of IOSONO (Erfurt, Germany), a technology company with expertise in immersive 3D sound. The transaction creates a new company called Barco Audio Technology. Barco also has a partnership with Auro Technologies that has resulted in the commercialization of the Auro 11.1 cinema audio solution that has now been deployed to over 500 theaters worldwide.

To learn more, we spoke with Brian Claypool, senior director of strategic business development at Barco. He explained that IOSONO first did a demonstration for the Hollywood community back in 2008 where the company outfitted the Chinese Mann theater with an array of speakers. Using the Wavefield Synthesis technology, Barco moved sounds all around the theater in one of the first theatrical demonstrations of immersive 3D audio. The demo was a success, but the cost of outfitting a theater will all the speakers and a dedicated new workflow was just too much for industry to adopt the approach.

However, IOSONO has found success using the technology in purpose-built entertainment and other venues where the costs can be more easily justified.

In the meantime, Dolby developed its Atmos solution which seems not too dissimilar to the IOSONO approach. Barco chose not to pursue this path at the time, focusing on the Auro Technology and the Barco Auro 11.1 solution. This solution was designed to minimize the investment theater operators would have to make in new equipment, with minimal impact on the audio production workflow.

The Auro 11.1 system is physically like a double-stacked 5.1 audio system – that is, it offers two rows of speakers around the theater with the second row placed above the first row. Each row of speakers has three speakers in the front and a bank of speakers running along the walls of the theater and onto the back wall.

The lower row of speakers acts like a normal 5.1 audio layer with left, right, center and subwoofer tracks coming from the speakers behind the screen, and the surround tracks played back through the bank of speakers on the walls and back of the cinema. The second layer of speakers is used differently. Here, the audio is mastered to create a height layer and an overhead layer. These help to create the impression of a dome of audio with the ability to move beyond the plane of audio offered by a 5.1 system.

As interest in object-based immersive audio has increased, Barco decided to re-evaluate the IOSONO technology finding it now offered a good complementary fit with its audio efforts in cinema as well as other lateral markets like simulation and augmented reality. The acquisition of IOSONO will also be useful for Barco as it rolls out the new 20.1 sound solution.

The Barco 20.1 immersive sound solution (no formal name yet) will add more speakers to the configuration in the theater. It also appears to scrap the legacy 5.1 component in Auro 11.1 and focus on using all the speakers in a new way. These speakers will now be effectively clustered into zones. Each zone can have one or more speakers attached to it. There will be six zones in the front (high bank and low bank), four zones on the right, left and back sides (high and low, font and back), and two overhead zones, plus the subwoofer (.1).

Claypool noted that this will expand the 11.1 speaker configuration a bit but provide more immersive sound – with the help of IOSONO technology. The speakers do not have to be rewired in the theater as each speaker typically has a cable running from it to a dedicated power amplifier. “What is different is the way we will process the audio to deliver it to the bank of amplifiers”, said Claypool.

One major challenge for all the new immersive sound formats is being able to deliver the same audio experience no matter where you are in the theater, instead of just one small sweet spot. “This is something we and Dolby struggle with as there are some physics limitations to be able to do it”, said Claypool. IMAX may be a little better at delivering a bigger sweet spot as it has closer control over the design of the theaters that Barco or Dolby do in the general cinema market (see related story on IMAX 12 – track immersive solution).

Development of standards to support the deployment of object-based audio is also moving along nicely within SMPTE. Here, the idea is to develop an open standard for the immersive audio package that all post houses could render to. This open format would describe each audio object along with metadata that details its “flightpath” and amplitude in the theatrical space. At the cinema, processors would then take this metadata and render each object into channels in a way that best delivers an immersive audio experience for those speakers and that set up in that particular theater.

This idea of delivering an immersive audio package and rendering per the specifics of each theater is what Dolby has developed with its Atmos system. What SMPTE and Barco are trying to do is make the studio/post render of the immersive audio package an open standard, not the proprietary one that Dolby uses now for Atmos. That would allow Barco, Dolby and others to then innovate on the processing to turn objects into tracks to feed the speakers in the venue.

This seems like a sound and reasonable solution, which Claypool is optimistic can be achieved. When asked when this might happen, he said that in his discussions with the studios, they are hoping this open standard can be approved within 12-18 months. Let’s hope so as an open standard will also clear the course for object based audio to roll out many other platforms like home AVR receivers, Blu-ray players, set top boxes and more. We will keep you posted. – Chris Chinnock