What to think about when you think about hearables
It seems everyone I know is sending me news of Here Active Listening, a Kickstarter pitch for “the world’s first true hearable” that promises to retune your world. Here is essentially a hearing aid — it listens to the world and plays you a different version of it — but you know, a cool one, for cool people, not icky deaf people. It’s Instagram for your ears. It can mute annoying babies. A lot of people are excited by this, and Here have raised over £600,000 from baby-haters and people who think the world needs tuning on Kickstarter, a vast sum dwarfed by the $17 million parent company Doppler Labs just raised from investors. Everyone thinks Here is great, because none of them have ever used assistive hearing technology.
I am excited about the rise of hearables, because I wear a pair of hearables every day, and have done since I started going deaf in my twenties. I wear them from the moment I step out of the shower in the morning until the moment I lay down at night. Anything that focuses more time and money and creativity into hearing devices is a great thing for me. Yet this experience also grants me a great big pinch of salt to take with all this “hearable” razzmatazz. I’m going to use Here as an example, but really these observations can be applied to almost all the herable tech you’ve read about, and most the hearable tech you will read about in the years ahead. Consider it your primer.
I hacked my own hearing aids last year — making me the first human who could hear Wi-Fi fields — partly to demonstrate the kind of potential that comes from wearing always-on, networked, personal audio devices. One of the phrases me and my collaborator Daniel Jones bandied around during that project was “Google Glass for the ears” and I genuinely think devices such as the Starkey Halo and ReSound LiNX, which can connect wirelessly to a smartphone, deserve that name. Hearing becomes a platform. It’s exciting to think about what can be built in that space in the years ahead.
With that in mind, I think the Here team are onto something good, if a little behind the game. Because despite what the makers claim, it pretty much is a hearing aid, and it’s certainly not the world’s first hearable. Even bog-standard hearing aids allow different presets to tune your world, most have automatic noise dampening, and higher-tier models come with smartphone apps that let you adjust equaliser settings in exactly the way Here promises to. I can play music wirelessly into my hearing aids. I can take phone calls through them. I can hear better with them. Here distinguishes itself by saying that it is none of these things — not a Bluetooth headset, or a pair of headphones, or a hearing aid. I expect it does its chosen job of airbrushing your audio landscape quite well. But in the language of tech writers, in the existing ecosystem, it’s not a features-rich product.
My principle issue with Here devices — and this is something you ought to look out for in all future hearable technology — is that they seem to rely on a fully-occluded headphone to work. That means the little soft bit that goes in your ear completely seals your ear-hole. It’s essential if you want someone to only hear the output of a device, without it mixing with sound from the outside world. You’ve likely seen them sold as “noise isolating” headphones. They’re great for listening to music, because all you hear is the music.
However, full occlusion is terrible for anything except listening to the device. It creates a very common problem known as the Occlusion Effect. The pocket of air trapped between the earbud and your eardrum amplifies internal vibrations. Try eating some crunchy cereal with occluding earbuds in. It’s deafening. As if that’s not enough, with full occlusion you lose the ability to judge the volume and tone of your own voice, as your perception of internal sound is off. As a result, you find yourself talking weirdly, and then you find yourself not talking much at all.
This is one of the reasons that almost all hearing aids have a vent — a clear tube from one side to the other — that equalises the pressure between your ear and the outside world, allowing the internal vibrations to escape. It doesn’t solve the problem entirely, but it helps. My completely-in-canal (CIC) style hearing aids (imagine a pair of earbuds with the wires sliced off) have vents, but I still can’t eat with them in, it’s just too damn noisy.
Now, creating a vent means that sound from the outside world will leak in to your ears. That’s OK for hearing aids, because you’re trying to add sound, not remove it. But any device hoping to become an everyday wearable will struggle to deliver true noise reduction, because the experience of full occlusion is so uncomfortable long term.
In their defence, the Here team does say that their device is for episodic use, to rejig sound levels at concerts and so forth. But they also make clear that the idea is for much more pervasive wear in the future, a dream shared by others fantasising about the hearables future. This raises some problems, the next of which is also related to full occlusion.
As well as trapping air in the ear, closed buds will trap moisture. And as you all know, bacteria love to grow where it’s warm and wet. I endured a lot of mild ear infections when using CIC hearing aids (even though they have vent!). Having something sit in your ear all day can also irritate the delicate membrane of your ear canal, which is painful. I’ve yet to experience similar problems since I switched to behind-the-ear (BTE) hearing aids, which sit where the name suggests they do and send sound to the ear via a very slender, non-occluding tube that snakes into the ear canal. So if you plan to wear a big fat fully-occluding hearable all day so you can shut out the sound of screaming babies and unacceptably balanced music, I expect you’re going to suffer an increased rate of ear infections. Sorry the future isn’t all sleek white plastic and chrome, kids.
Next on our list of problems is that it is functionally impossible to recreate the sonic environment on something the size of a kidney bean. I really wish this wasn’t the case. It would be good news for me and millions like me if it wasn’t the case. But so far, it is. It would take several essays to explain the problems in detail, but for now accept that we simply don’t know enough about how hearing works, and we don’t have the technology to replicate it. One reason hearing aids are so difficult to make is that you’re trying to reproduce your acoustic surroundings to an acceptable level using a set of tiny microphones nestled against the head. I welcome any progress that Here can deliver to resolving this problem, but I want you to understand that recreating acoustics is not as simple as having a device with a microphone at one end and a speaker at the other and putting it in your ear.
Speaking of that microphone, the Here devices look as though they have lovely giant microphones jutting out from the device. My behind-the-ear hearing aids might escape the cereal-munching occlusion problem, but being external raises another one: they suffer wicked wind noise. Imagine someone blowing over a microphone. It sounds just like that, because that’s what it is. Even a light breeze is enough to drown out any other sound. I have to take them off in the gusty Tube. I have to take them off when I cycle. This can be addressed with software, and design too, and perhaps the sheer gargantuan size of the Here devices will help in this respect, allowing more room to play. But I wouldn’t recommend buying any hearable that relies on listening to the environment until you’ve tried wearing them in a stiff breeze.
At this point, I should also raise the question of battery life. Here claim six hours for their devices. My hearing aids are half the size, and last a week. I’ve no idea how Here are hammering their batteries so hard. But know that the benchmark for hearables is a week on a battery smaller than an aspirin.
Finally, a word on the price. Creating a good “hearable” is very difficult. Prices reflect that. An entry level, standard NHS-issue hearing aid is in the region of £750 ($1,200). A top-of-the-range, noise reducing, speech focussing, iPhone-linked LE Bluetooth device is around £2,400 ($3,800). That is the price per ear. Yes, you read that right. My hearables cost ten times more than your fancy upmarket Beats headphones. So, can Doppler Labs and their contemporaries deliver what is effectively a comparable product at $249 a pair? I have, to put it mildly, strong doubts. I hope they can, of course. Perhaps by trading off size, battery life and audiologists appointments they can. The hearing aid industry is ripe for a shake up from a punchy young startup, and if someone can figure out how to create similar products at a fraction of the price and sell direct to consumers, kickstarting (haha) the hearables market, I’ll be first in line. In the meantime, temper your expectations.
