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Bluetooth headphones: the eternal struggle with incomprehensible phone calls
by Dayan Pfammatter
Auracast – everything you need to know about the new Bluetooth standard
3.4.2024
Translation: Patrik Stainbrook
With Auracast, a device can send its audio content to an unlimited number of end points. This opens up many new possibilities. More and more devices that support the innovation have been coming out since the beginning of 2024. But what exactly is it, and what can you do with it? Allow me to explain.
But where does the standard come from and how was it made?
What is Auracast?
How does Auracast work?
You can think of Auracast as basically a radio program. A central device broadcasts audio content, all devices that support Auracast can dial in and listen in. The big difference? Unlike radio, which is broadcast terrestrially via transmitting antennas, Auracast is based on Bluetooth. The range of the signal is therefore still limited – walls, doors and the like restrict it. The (very) theoretical maximum value is 400 metres.
On a technical level, you can think of it more like a hotspot or public Wi-Fi. It’s also very practical and comparable. If you search for Auracasts in your area, they’ll be listed for you – each Auracast has its own name. And just like public Wi-Fi or a hotspot, they can either be open to anyone or encrypted. You’ll need a password to receive content from those.
As you don’t have to pair your headphones directly with the transmitter via Bluetooth, an infinite number of devices can be connected to the Auracast. If you have a speaker or headphones connected to your smartphone as well, the content can also be played back there – even if the headphones don’t support Auracast. The signal is transmitted in LC3, the new Low Complexity Communication Codec, an uncompressed alternative to the widely used audio codecs SBC or AAC.
You can also access Auracasts via a QR code or NFC. So if you have NFC-enabled headphones, for example, you won’t even need a smartphone to join Auracasts. As with Spotify, for example, metadata is also transmitted via the audio stream in addition to audio signals. This means an Auracast not only has a name, but can also relay what’s currently being broadcast – such as the name of a song and artist or information about a program.
How can you use Auracast?
How do I join an Auracast?
If your headphones support Auracast, it’s very simple. Connect them to your smartphone, then tap on the corresponding device in the Bluetooth menu and on Scan Auracasts (the exact wording may vary). The list of available Auracasts will then be displayed, as well as whether you can join them.
Hearing aid manufacturer Resound, for example, shows how this works for them in a YouTube video – it’ll be similar on other devices.
Do my devices support Auracast?
However, Auracast support can be delivered later if Bluetooth 5.2 is supported – regardless of the manufacturer. You can only be absolutely sure if you check your device yourself.
How do I start my own Auracast?
You essentially set up an Auracast like an Internet hotspot or a Bluetooth connection. Connect the speaker to your smartphone as normal via Bluetooth, then press the Auracast button on the connected speaker as well as all others. Music from the smartphone will now play on every speaker. However, this is currently still limited to JBL speakers such as the Xtreme 4.
Samsung has integrated Auracast into the Bluetooth menu of its latest premium smartphone series, the S24 models. With them, you can start an Auracast in a few clicks. Otherwise, it’s still difficult – there aren’t that many devices that support the standard yet.
What’s the legal situation?
In principle, you can download music from the Internet and use it for «performances» in a very small circle. In other words – if you start an encrypted Auracast and, for example, your flatmates join in, you can also stream content that may be copy-protected.
The initial situation around unprotected public Auracasts is still unclear – especially as the legal situation varies from country to country.
How do providers such as Spotify and co. react to this «one-to-many» function in Auracast?
This question is still completely open. Unlike Chromecast or AirPlay, for example, a receiving device doesn’t have to be in the same Wi-Fi network to play content.
What’s more, with a public Auracast you can’t even control exactly who and how many devices connect. It isn’t yet clear whether these app developers will restrict Auracast access or how else the problem will be solved.
Header image: Shutterstock
I've been tinkering with digital networks ever since I found out how to activate both telephone channels on the ISDN card for greater bandwidth. As for the analogue variety, I've been doing that since I learned to talk. Though Winterthur is my adoptive home city, my heart still bleeds red and blue.
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