One of the great things about being an engineer is that you occasionally get to see the products you design being used. It’s difficult to describe the emotion when you see someone you don’t know getting value from something you’re responsible for.
When you’re involved in standards, that can be even more powerful, as you see the effect of having bounced ideas off other people, where the resulting whole often seems greater than the sum of the parts. In some cases, you also see people using the products in ways you’d never imagined, discovering new ways of working and enhancing their lives. That has been one of the greatest rewards of working on Auracast™ broadcast audio.
How it started
The journey started back in 2013, when a small group of hearing aid companies came to the Bluetooth Special Interest Group (SIG) to ask if they could collaborate to make hearing aids work better with mobile phones. I was at a conference in Shanghai, and, out of the blue, I was asked if I could help by chairing that development. The intervening years have been a fascinating journey.
The initial intention was to find a low-power way of getting audio from phones and PCs to hearing aids. Nothing too revolutionary, but it needed to be much lower power, as hearing aid users typically wear them for around ten hours a day without taking them out to recharge. So, minimising power consumption was vital. They also wanted to support stereo. This was before anyone had thought of wireless earbuds, so it was breaking a lot of new ground.
The biggest innovation was to find a way for the same audio to be distributed to multiple sets of hearing aids at the same time. That would mimic the experience that hearing aid users had with inductive audio loops. These, known as telecoil loops, were used in theatres and public buildings to help hearing aid users pick up the same audio signal. That was something Bluetooth® technology had never done before. All Bluetooth audio products had a one-to-one connection. The approach had always been for a user to send a single audio stream from their phone or PC to their headphones or speakers. Now, multiple people could listen to the same audio at the same time.
That may sound pretty simple, but the subtleties get very interesting. That became obvious when we started talking to people with hearing loss and people who are passionate about the quality of their music. Those two communities drive very different design paths in the hearing aid and consumer audio industries. The latter has become focused on ultimate audio quality but often sees that as a common nirvana for all of its users. In contrast, the hearing aid industry is very aware of the different levels and types of hearing loss their users face and puts a lot of effort into allowing each of them to customise their hearing experience. At the most basic level, it allows everyone to set their own listening volume.
Individual audio control
Providing individual control is a subtle difference in perspective, but it has a major effect on the way that we designed Auracast™ broadcast audio. If you think of a family sitting listening to their TV, some may be listening to the ambient sound from the TV while others may be using hearing aids. Traditionally, that leads to an argument about the volume level, with everyone fighting to turn it up or down. With Auracast™ broadcast audio, each set of hearing aids has its own personal volume control, independent of what the TV is doing. Everyone can listen at the volume they want. Each individual can switch from the TV to take a phone call without interrupting the other family members. For the first time, everyone can do what they want independently. Which is turning the way Bluetooth audio traditionally works on its head.
One other innovation was the realisation that those family members might not want to listen to the same audio stream. As TV streaming has developed, some of the streaming companies have realised that many soundtracks can be difficult for some viewers to follow, especially where there are loud background noises or music. Film companies have known this for years and include audio accessible tracks which reduce the background noise and enhance conversations, which are usually sent to the telecoil installations in cinemas. TV streamers have started doing this as well, but have had no way to separate the streams for different listeners. Either everyone had to listen to the normal stream, or everyone had to hear the accessible stream. Seeing the opportunity to make life easier, we designed Auracast™ broadcast audio so that it could transmit multiple different audio streams at the same time. Once again, the choice of what to listen to is made by each listener.
The ability to transmit multiple different audio streams is not limited to a choice of a normal or accessible stream. They could also contain different languages. So, some listeners in the room could watch a program in Korean while others could choose a dubbed English version.
Seeing the opportunity to make life easier, we designed Auracast™ broadcast audio so that it could transmit multiple different audio streams at the same time.
Adopting Auracast™ broadcast audio
As we started to explain and prototype these new ways of listening, we found that the consumer audio industry became very interested in the new possibilities. Shortly after we’d started working on the new specifications, the first Bluetooth® wireless earbuds had appeared on the market. These solved a few of the problems we’d identified in proprietary ways, but were just a stepping stone on the way to what we were aiming for. We suddenly found a much wider audience for the features that were being developed within the Auracast™ solution. What was fascinating was that they didn’t just come from the members designing the specifications or their companies. Alongside their input, we actively went out and talked to potential users, taking their feedback into account as we developed the new standards.
Fast forward ten years, and we released the first group of specifications. For those of us writing the specifications, we knew that we would need to be patient before we saw products come to market. Miniature products like hearing aids and earbuds are incredibly difficult to design and manufacture. We were also aware of how many steps it took to get inductive telecoil loops deployed in buildings and public infrastructure — that was a process that traditionally took decades rather than years. But we were about to be surprised.
As the first products started to appear, we began to see a new level of excitement coming back from early adopters, as well as larget scale implementers. Normally, with new technology, those early adopters are young and enthusiastic, but this time we saw a much wider range of feedback. We also saw an unexpected range of products. There were hearing aids and Auracast™ transmitters, which addressed the original use cases, but there were also party speakers, which people could connect together for impromptu parties. Smartphones started to include applications which let you share a music stream with friends. TVs included Auracast™ capabilities, ready for new use cases.
Most importantly, people started playing with these new products, doing things we’d expected but also thinking up new uses we’d not envisaged. The biggest surprise was that infrastructure owners, such as theatres, churches, and even bus operators, took the plunge and started experimenting. It normally takes between five and fifteen years for hearing assistance to be specified and installed in public spaces. Now, people were buying Auracast™ products online and doing it in five days.
Continued Auracast™ momentum
As momentum has gathered, I’ve been fortunate to visit and talk to many of the people who have made these installations happen. I’ve heard Auracast™ broadcast audio in small village halls and large theatres. I’ve spoken to a composer as one of his works was broadcast by an Auracast™ solution in a major international concert hall. There have been conversations with people designing airports, train stations, schools, and railway carriages — all of whom want to use Auracast™ broadcast audio in interesting ways.
It’s also being promoted at hearing wellness festivals. During World Hearing Day on 3 March 2026, many people experienced the potential of Auracast™ broadcast audio for the first time and loved it. An amazing number of different people are beginning to think about how shared audio can change the way they communicate, whether that’s for public information, new forms of entertainment, or just helping everyday conversations.
We’re getting fascinating feedback about how Auracast™ broadcast audio can help people who have issues with crowds and noisy environments, helping them to have better experiences when they’re out in their communities. They’re also telling us what else they’d like to see (or hear), which is informing the next generation of specifications we’re working on.
We’re getting fascinating feedback about how Auracast™ broadcast audio can help people who have issues with crowds and noisy environments, helping them to have better experiences.
It is an absolute joy for us to see the way that Auracast™ broadcast audio is being taken up and used. If you’ve not experienced it yet, it’s coming your way and will soon be in your phones, TVs, PCs, earbuds, and the buildings and infrastructure around you. It’s changing the way that we’re able to use audio, bringing in a new wave of innovation. I don’t think any of us expected this return when we started, but it has been a privilege to be part of its development.
