‘Audiences will not notice object-based audio until it’s not there’
PSNEurope’s Phil Ward delves into the world of immersive technology and how it is shaping the pro audio market.
Forget ‘360’ sound. If immersive audio is going to mean anything significant in the coming years, it won’t be because a few Pink Floyd remixes can mess with your head in a museum. No disrespect is meant to the superb use of Sennheiser’s AMBEO platform at the Victoria & Albert Museum in London during the exhibition Pink Floyd: Their Mortal Remains, but when it comes to core live music such as rock, classical and indeed any other style, there is a fundamental requirement to deliver a solid mix to an audience at least familiar with the programme. For this, 180° systems are enough.
This is where the new generation of object-based sound reinforcement is going to make a real impact – or perhaps no impact at all other than swathes of new-generation ticket buyers curiously more happy than ever before with their experiences. It has long been a goal of reinforcement in classical and operatic productions to become invisible, if we can set aside this irrefutable case of oxymoron. Blending into the room acoustics suits not only aesthetics but also the sensitive politics of arts booking in which, not to put too fine a point on it, stealthy sound engineers let sleeping puritans lie. Object mixing is only going to make this job easier.
Blind test
As for pop and stage musicals, pro audio may be accepted as part of the stage package, but even then comes wilfully low on the list of ingredients that might make a difference. Here’s an extract from a telling review of The Last Ship, Sting’s new show about his roots in Newcastle now touring the country. It’s a highly favourable notice, but in her attempts to identify the source of her happiness, the reviewer – Kate Richards for the South Wales arts website Get The Chance – exhausts every possibility except the correct one: “My instant reaction to the opening few bars of The Last Ship was ‘wow what a sound’! I found myself trying to rationalise why the quality of the sound had made such an impression on me – were these particularly exceptional singers, are the acoustics in this auditorium better than other venues or could it be that I just don’t hear live music often enough?”
Try as she might, Kate just cannot get to the heart of the matter even as she leaves the Wales Millennium Centre a happy customer. “By the end of the production,” she concludes, “I had decided that the phenomenal sound was a combination of all three elements – there are some absolutely exceptional singers in this cast, the auditorium does have great acoustics and yes, there really is a huge positive difference between the immersive experience of listening to live music in a theatre versus the usual way I consume music these days – the digital radio in my car or occasionally on a mini-speaker around the house.”
Were it not so amusing, it would almost be an insult to a sound system that deploys a 180° version of Soundscape, d&b audiotechnik’s object-based processing platform. Sebastian Frost, the sound designer of The Last Ship, takes being completely ignored like this as the greatest compliment. “Absolutely,” he says. “Our job is not to make our presence known. It can be felt, I guess, but not known. It’s nice to have any appreciation of what one does, anyway. Funnily enough, the new systems allow greater creative expression rather than less. A lot of the time in a venue is spent dealing with the inadequacies of the design, the acoustics and indeed the production itself, in a highly technical way. With all of these new tools you find ways of using them far more constructively, and you have a lot more time to do so. It levels the playing field in a way that re-sets the sonic environment to what it truly should be, in the truest, most natural sense. That allows you to add your own style.”
You also have space to add the unnatural, should it be required. Serge Gräf, nowadays using Soundscape while mixing FOH for those sonic pioneers Kraftwerk, gets a similar response even though he is using the 360° system to its full potential.
“I asked some non-audio professional friends what they thought of the ‘surround’ after one show,” he recounts, “and they said ‘What? There was surround? We just thought each voice was coming from where could see them…’ So this shows that even without tracking technology you can solve most of the localisation issues in a convincing way, even for people on completely the opposite side of the auditorium.”
Local brew
Localisation is the key. Advanced products like Out Board’s TiMax SoundHub and TiMax Tracker have been cracking this particular chestnut for some time, but if accurate-enough localisation can be achieved using an essentially proscenium concept more or less right out of the box then more audiences than hitherto possible will at least get a hint of what they’ve been missing. Or again, what they haven’t been missing because nobody told them it wasn’t there.
Sound designer Kai Harada has been using Astro Spatial Audio’s SARA II Premium Rendering Engine, an application of The Fraunhöfer Institute’s SpatialSound Wave technology, for the musical The Band’s Visit on Broadway. In fact, he’s won a Tony Award for it, so people are noticing something, even if it’s not a new paradigm in sound mixing. As he puts it: “The best compliment we can receive is if the audience didn’t notice the sound system: then we have achieved our goal of simply reinforcing the natural sound of the voices and instruments.”
But he is in no doubt that Astro Spatial Audio (ASA) will change the way he uses conventional PA speakers. “I think the benefit of ASA’s system and topology is that I can still design a more ‘traditional’ sound system designed for coverage and optimised for different types of sources, but put SARA on top of it all,” Harada says. “Of course I was apprehensive about such a new piece of equipment, but it worked flawlessly and I appreciated the time that [ASA founder] Bjorn van Munster spent with us. I think the ability to easily manipulate localisation as well as room acoustics will be very beneficial for future shows. The speakers themselves don’t need to change much, but we may be able to become more flexible with loudspeaker locations provided we have enough power, as the ASA system can do a lot of the math for localisation without too much user intervention.”
Another significant point Harada makes concerns the misapprehension that these new systems presuppose some kind of surround experience.
“To be absolutely clear,” he says, “we are not creating a 360° immersive experience at The Band’s Visit. It’s still a traditional musical in a proscenium theatre. We are simply using an object-oriented approach for specific sound sources, to great success. With live theatre, I think there is a world where we can have more fun with sound sources in different locations, but it has to be specific to the type of show: it wouldn’t make sense, for example, to do a classical musical with multi-channel sound sources and the violins coming from behind you. That’s not appropriate to the show.
“However, I think that as theatre creators come up with new and interesting ideas there may be a world for such effects.”
“The 180° techniques are far more important,” emphasises Frost. “They’re totally separate things, and they give different results. We’ve been able to re-shape room acoustics, or do stage-tracking, or other forms of ‘surround’ for some time. What we haven’t been able to do is to replicate sound sources in a natural manner, in a way that’s true to what you’re seeing in front of you.”
Pink noise
L-Acoustics makes an important distinction within its L-ISA object-based audio ecosystem between ‘immersive’ systems and what it calls ‘hyperrealism’: the former concerns extended 360° solutions, while the latter is the frontal arrangement that we can identify as ‘180’. Sound designer Colin Pink deployed a hyperreal configuration of L-ISA Live at the Classic BRITs recently, an awards night of speeches, solos and orchestra at the tricky Royal Albert Hall in London.
“When you start using L-ISA,” Pink explains, “the first thing you notice is the greater separation that you have. It allows you to place each instrument where you want it, and the off-axis imaging is quite remarkable. The whole premise of restricted stereo imaging of old is eliminated, and this is the biggest change that you are aware of. Because of it you get a lot more detail, and you can really focus on all of the different elements of the mix.
“You also get a lot of headroom, simply because you’ve got more hangs, even though they’re smaller. You’re distributing your energy among them, so everything sounds a lot more effortless. It allows you to be more creative with your mix, too, because you have those extra dimensions of width and depth and the greater accessibility of placement.
“What’s really interesting is that you push the faders up and you get a good mix quite quickly. It’s much quicker to hear what’s going on and how different instruments are working either with or against one another. That is a really important part of this evolution.”
Sergey Becker is L-Acoustics’ UK application engineer for touring, and has his own theory about typical audience nonchalance. “As with anything else,” he points out, “psychologically we take good things for granted. If the frontal part of an L-ISA Live system is compared to conventional stereo the change may seem subtle at first, and the difference is much more apparent off-axis. In the centre, the difference between stereo and L-ISA is audible, but off-axis is where it really shines. At the Albert Hall 70% of the audience was within the L-ISA zone and had this experience. Even in the middle there is much greater amount of discrete separation and clarity.”
Rock follies
Most engineers who have used object-based audio agree that, once tried, it’s a disappointment to have to go back to stereo. But they’ll have to, for a while.
“There is still an expense attached,” points out Frost, “and it can be challenging to install. It’s not something that’s going to apply to all corners of the industry, for some time to come. Nevertheless, I think it is where everything needs to end up going.”
One may assume audiences will notice too, even if they won’t know why. All of which, as we sanction these silent assassins of bad sound, will contribute to a greater mass suspension of disbelief than ever before – which is a sub-conscious process at best. It may even be unconscious, at some gigs… In the opinion of Eddie Thomas, founder of ETA Sound and now SSE Audio’s large-scale installation guru, even if object-based mixing does transform rock sound, its audiences will be the last to pay it any heed.
“They just want it to be loud, while they all get drunk and fight,” he says with tongue partly in cheek. “Isn’t immersive audio wasted on that market?”
He may have a point…
Source: mi-pro.co.uk
