The Science of Sound

Port discovers how a new start up is revolutionising the audio industry by thinking afresh about how we hear

Otoacoustic emission – the minute sound generated by the inner ear in response to stimuli – was first theorised by the astrophysicist Thomas Gold in 1948, but it wasn’t until some thirty years later that the theory was confirmed with a measurement in a laboratory. So faint is this sound produced as a byproduct of hearing – 10,000 times weaker, in fact – that it takes incredibly precise equipment, and very sophisticated and specialised processors, to detect and analyse. When the phenomenon is measured in newborn babies in hospital, to measure their hearing, a large machine is wheeled into the ward and plugged into a wall outlet. 

“It’s like sitting in Vienna, looking up at the Matterhorn with a telescope, and trying to determine whether someone placed a pebble on top of the mountain,” says Dragan Petrović, the CEO and co-founder of new audio company nura. Sat in a cafe in east London, he is explaining to Port how, in no small feat of engineering, his company has managed to reduce the unwieldy hospital equipment to fit inside a normal pair of over-ear headphones, and in the process revolutionise the way we think about music. 

“nura really started by us thinking about how there has been no better time in history to be a music enthusiast,” Petrović continues. “All of the world’s recorded music is at your finger tips, instantly available through your phone or computer in high quality. We got talking about how all of that passion and creativity, all the effort and understanding that goes into the recording, into mastering the music perfectly, flows to the speaker in your home, in your car, in your headphones. We asked ourselves – is that the end of the process?”

The answer, Petrović and his team found, was very much ‘no’. 

“That process doesn’t end at your smartphone or your computer, it needs to come into your mind. You need to understand it and hear it in a way that has lost none of that creativity and passion.”

It’s a simple enough problem – preserving the sound and experience from the recording studio to the listener – and one that audio companies the world over have claimed to solve with ever more sophisticated and expensive equipment. But no one before nura has thought to look into how we hear.

“It’s kind of like saying there’s a perfect shoe or pair of glasses for everyone, but of course our feet, or the way we see, is completely unique, and it’s the same with how we hear.”

And quite considerably unique, too. At any given tone, one person’s sensitivity may differ by 20 decibels – seven clicks on your phone’s volume button – a huge amount that is not accounted for by any high-end audio equipment. If nura could figure out how to measure an individual’s hearing and tailor the sound to them, it would be a wholly new approach that could leapfrog even the most specialised and expensive speakers or headphones. 

It was a big ‘if’, and it took two whole years to go from the concept to having a product that was ready to ship – a considerable amount of that time being spent working out a model that would be able to decode information about your hearing, and use that to create a hearing profile. The idea, however, proved popular and when nura sought funding on KickStarter, the company raised close to £1,500,000. They had set a target of £75,000. It was the most successful KickStarter in Australia, where the company is based.

When Port meets Petrović, we have already had the nuraphones in the office for some time. Ready to use out of the box, we download the app that is required for calibration and put the headphones on. Though at first the unique combination of over and in-ear takes some getting used to (highs and mids are played through the earbuds while the bass comes through a second speaker in the ear cup, so you can feel the sound), it is comfortable and surprisingly lightweight given the technology it contains. And stylish, for that matter – the matt black round metal cups and headband are subtle and sleek. 

Making sure there’s no background noise, we start the calibration process. A cascading range of frequencies – like something appearing or disappearing in 70s sci-fi television show –  are played for around a minute before a sample song starts. It sounds ok – a bit flat, perhaps, but otherwise passable. Then you switch on the personalisation and the music erupts in colour, the smudge of various instruments separating to be intricately defined parts of a now rich, elaborate whole – the highs sharp, the mids full and the bass tactile and profound. There’s a rush to rediscover old music, favourites suddenly thrust into relief, revealing shapes and shadows that were never there before – the scrape of fingers along strings between chords; Glenn Gould humming along as he plays Bach’s Goldberg Variations. 

The headphones, then, are clearly excellent but to what extent is this down to the personalisation, as it is to the quality of the design and components? Could it be that the equaliser was just artificially flattened when personalised mode was turned off? To find out we passed the headphones around the office, adding new profiles alongside the original, and then compared. Listening to music on someone else’s profile was still impressive – the headphones offer great passive (and, with the recent software update, active) noise cancelling, and the immersion mode adds haptic feedback to emulate the feeling of being at a gig, but switching back to your profile, the difference is palpable. Like putting on glasses that correct for colour blindness, you realise that it is only now you are seeing the whole picture.

With such groundbreaking technology, it’s a wonder why the nura team undertook the considerably longwinded process of developing the hardware themselves, rather than licensing the idea to established companies. But, as Petrović points out, we are experiencing now the final, polished and successful realisation of an idea that by itself would be a hard sell. “When you do something as new as this, you have to prove it works,” he explains. “The headphone market stayed the same for so long – of course there were some great advancements with wireless technology and active noise cancellation, but there hasn’t been a big breakthrough in sound for a long time. We’re going back to why these things exist in the first place – to play music – in a very new way, and we needed to do everything ourselves, to be there from developing the software, to the manufacturing [the nura team moved to Shenzhen in China to oversee the final phase of the nuraphone’s development] to collecting and processing anonymised information about how we hear to improve our technology further.”

Needless to say there have been some “inbound inquiries” about the nuraphone technology from other audio brands but, for now at least, nura remains focused on developing the product themselves. Having received rave review from almost every major tech blog, it seems nura looks set to become a major player, the young upstart disturbing the status quo.

Where will the company go from here?”

“I can’t say anything too specific,” says Petrović, smiling. “But there’s a lot in the works. We’re still looking to improve the experience on the existing product with new updates. Our mission statement is to deliver perfect sound to every individual in any situation, so there’s a lot more work to be done.”