Auracast and the Evolution of the Earbud Case
- in Hearables
Sometimes, it needs what seems to be a small, tangential innovation to make a product successful. At the time, it may not seem much, but it can result in the product acquiring a life of its own. One product which is making its way along that trajectory is the humble earbud charging case.
The history of the charging case is quite interesting. Stereo wireless earbuds were a long time coming. It needed some serious technical innovation by a couple of chip companies to make them possible – new technology by Cambridge Silicon Radio (now part of Qualcomm) to let them receive and render separate left and right audio channels, and small near-field magnetic induction chips from another silicon company – NXP to send wireless signals through our heads. It then needed the brilliance of a German startup called Bragi to turn these concepts into working stereo earbuds, kickstarting the whole hearables market. It has become the fastest growing technology product ever, eclipsing even the iPhone in its growth.
By themselves, wireless earbuds can have a problem – the battery life is disappointingly low. The early models could only play music for little over an hour before they needed recharging. Bragi and Earin (another pioneer in those early days) developed a charging case where you could store your earbuds. The charging case had a larger battery, allowing you to use your earbuds all day, but with significant gaps while they were recharging.
Apple played a very clever card with its Airpods, designing an easy to use charging case which tempted you to put your Airpods back into it whenever you weren’t using them. The physical shape of the Airpods played to that usage model. Accompanied by successive, incremental improvements in battery life, users finally began to feel that they really did last all day. However, as we saw with phones, where battery life used to be a major factor in choosing a phone, as soon as battery life improved, manufacturers started adding new features, such as Automatic Noise Cancellation (ANC), which ate up the improvements. So, despite the improvements, most peoples’ experience of earbud battery life has remained unchanged.
The other thing which has remained unchanged is the basic functionality of the battery case. Back in the early days of hearables, I started talking about how a battery case could evolve to do more than just charge a pair of earbuds. If you put a Bluetooth chip into the battery box, it can help with pairing, but more importantly, you can start to use it to control your earbuds, by adding volume and mute buttons. You can also use it to pause and stop music streams. None of these are difficult to do, but it’s taken a long time for them to appear.
The Arrival of Smart Battery Cases
That’s just started to change, with a new “Smart Battery Case” from JBL for their Tour Pro 2 wireless earbuds, which has touch screen that lets a user turn on ANC, see message notifications and control playback.
Most of these are things that you can already do with a smart watch, but now you don’t need to buy a smartwatch. The battery case even tells you the time. JBL claim that putting controls that are easily accessible on the battery case make it up to seven times faster to access features on your earbuds, compared with using an app on your phone. That’s a common complaint that is heard from earbud and hearing aid users, who find that the time it takes to open an app and change settings is far too slow. They would much rather have instant control.
As far as I can see, JBL’s Smart Battery Case doesn’t let you change volume. However, another startup company – Olive Union, has taken the lead. They’re currently approaching the fulfilment stage of a crowdfunding campaign for their latest hearing aid and have supplemented the offering with a small remote control which clips onto the bottom of their charging case.
In some respects, Olive’s Remote Control is an afterthought, although the ability to use it separately can itself be a benefit. Like the JBL Smart Battery Case, it lets you turn on Noise Reduction, as well as controlling the hearing aid focused features of Preset, Focus and Hear-through. It also allows you to use it as a proxy to help the pairing process. It’s a very neat, low cost addition.
The Impact of Auracast
By themselves, these are both neat and fairly obvious evolutionary extensions to the earbud case, which shows that the Darwinian principle is working properly in the area of product development. What will turbocharge that evolution is the imminent arrival of Auracast. If you’ve not come across Auracast, it’s the marketing name that the Bluetooth SIG has given to the new broadcast audio capabilities that are enabled in LE Audio. The development work behind the Bluetooth LE Audio standards started off with a requirement to develop a solution which would provide an assistive hearing capability to work alongside the telecoil inductive loops that are currently used with hearing aids. It’s grown into a much wider initiative, which not only provides a new layer of assistive hearing, but can be accessed by any LE Audio compliant earbud or speaker. It supports very high quality stereo music, as well as multiple different language streams. It can be integrated into TVs, PCs and phones, where users can share their music with friends on an ad-hoc basis, opening up a new world of shared audio. In bars, gyms and airports, users will be able to listen to silent TVs. On public transport, they’ll be able to subscribe to travel announcements. It is likely to be the next big change to the way we consume audio and we will start seeing it appear in products in 2023.
If there is only one Auracast broadcast within range, it’s easy for your earbuds to pick it up – you either want it or you don’t. That’s the same experience as hearing aid wearers have with telecoil, as inductive loops for audio can’t overlap. With Bluetooth, transmissions will overlap, so an Auracast grows in popularity, users need some means to choose which one they listen to.
There are a number of different ways to do that. You can press a button on your earbud to pick up the first Auracast transmission it finds, then press it again to find the next one if that’s not the one you want. As the number of broadcasters starts to grow that becomes cumbersome, so the specification lets you use another device with a richer user interface to help make it easier. This utilises a feature which the specification calls the Broadcast Assistant. Device which support this capability can scan for available Auracast Transmissions and display a list of them, in a similar manner to the way that we scan for Wi-Fi access points. Auracast transmitters provide a lot more useful information about themselves compared to Wi-Fi access points, as they need to let you know the content of their audio streams. One way to convey that information, is to develop a phone app that does the scanning for you, like the example below, which has found two bus stops which are providing arrival information and two cafes that have their own music streams.
Once you’ve found the audio stream that you want, you select it. At that point, the phone sends the relevant information about how to synchronise to that specific Auracast transmitter over to your headphones, hearing aids or earbuds so that they can start receiving the audio stream that you’ve selected.
The interesting feature to note is that the phone doesn’t receive any of the audio content. Its role is limited to finding the available Auracast transmitters and what they’re broadcasting, letting the user select which one they want to listen to, and then providing whatever your hearable device is with the information about how to receive it. (Although they’re greyed out in the diagram, all of the other Auracast broadcasters are continuing to transmit their stream information and their audio content. The process is a way of allowing your headphones, hearing aids, earbuds or speakers to decide which one to use.) At no point does the phone receive or render any of the audio. It is just an enabler.
Because the only thing that a Broadcast Assistant does is to help find the broadcast, it means that this functionality can be implemented on a very simple, low cost device. Any product which already contains a Bluetooth chip and has a display can do it. Like a battery charging case. Taking the JBL case and thinking about what that might look like if it were upgraded to be a Broadcast Assistant, you’d expect something like this.
The end of the smartphone?
What’s important to grasp here is that you can now connect your earbuds to a source of music without the need for a phone. It’s something that is changing the status quo and causing some serious introspection amongst mobile phone companies, who see this as a potential threat to the future of the smartphone. On the other hand, they recognise that supporting Auracast in phones means that phones can act as broadcasters, allowing you to share music with your friends, something which has been sorely missing ever since phones with a music player capability first appeared on the market over twenty years ago.
There is little doubt that Auracast is going to change the way we consume music. As well as being a welcome addition for hearing aid users, its ubiquity and easy installation means that hearing assistance will become available in far more places. It also offers music sharing, access to multiple TVs and a whole new shared music experience to billions of earbud users. That scale is really important to recognise. Unless smartphone manufacturers start to embrace it, others, such as earbud manufacturers, will take advantage and become the product which people associate with their music and even use for controlling their phone calls.
It makes you wonder how long it will be before an earbud manufacturer adds a cellular modem into their battery charging case, turning it into an Auracast phone? When that happens, we may be looking at the end of the smartphone era.