What is oracast? Explaining the new Bluetooth technology

Listening to music via Bluetooth has become more flexible over the years. The distance that can exist between sender and receiver is not much greater today than it was in the early 2000s. Constantly improved codecs also increase connection quality and stability. However, the way we use Bluetooth hasn't really changed over this time. But this may be the case with the new Auracast functionality. As part of the latest Bluetooth specification, it has been designed to enable multiple Bluetooth headphones to connect to just one transmitter, for example to listen to a museum tour or a football broadcast in the pub.

Here we explain the new Auracast Bluetooth technology and how you can try it for yourself now.

What is oracast?

Auracast was launched in summer 2022 by the Bluetooth Special Interest Group (Bluetooth SIG) as part of LE Audio. The package includes not only Auracast, but also improvements in audio transmission quality using the new LC3 codec, as well as support for hearing aids. After a slow start, we are currently at a stage where the first smartphones, headphones and Bluetooth speakers are gradually using LE Audio. Auracast technology in particular saw a big boost at the technology trade show CES in January 2024.

In the full name of Auracast, Auracast audio streamingis the English word that means “transmission” or “broadcast”, Broadcasting. You can actually think of Auracast as a bit like broadcast radio. An Auracast transmitter, located in a lecture hall for example, broadcasts an audio signal via Bluetooth. This can be recorded by any number of receivers, i.e. by all students in the hall who have Bluetooth headphones with them. According to the Bluetooth SIG, the signal can theoretically be recorded in an area of ​​about 2,800 square metres, or more than ten courts in a game of doubles tennis. However, the range depends on the transmit power and antenna design.

Auracast as a messaging system in public places

Since Auracast allows multiple people to record a Bluetooth signal at the same time, the primary use for Auracast is clear: audiences. Bluetooth Sig Talking about it, that Auracast technology will make the world louder — something that's hard to imagine, given that Bluetooth headphones are designed to keep the world at bay. A television at an airport could be an example of this. Screens at the gate usually show the news with subtitles and the sound is muted. If this TV is Auracast-enabled, all interested guests can instead connect to their headphones and listen without disturbing sleeping travellers.

Likewise, TVs can be adapted in gyms or bars. Or ditch the old-fashioned headphones that museums often provide, and simply use your Bluetooth headphones to listen to an audio guide. Conferences and similar events that are translated into multiple languages ​​may also give you a choice of which translation you want to listen to.

Auracast as a hearing aid

Auracast also aims to help people with hearing loss. This means you can also connect to Auracast broadcasts with compatible hearing aids. Furthermore, the Bluetooth SIG is convinced that the high level of widespread use of Bluetooth can make this type of hearing aid accessible to people with different levels of disability.

Auracast for private music sessions

However, it is not only public institutions and event organizers that can install Auracast transmitters. Smartphones and laptops can also act as Auracast transmitters. In theory, in the future you could simply share your Spotify playlist on the train with everyone who wants to join. If you just want to let your friends listen in, Auracast allows password-protected transmissions.

By the way, Auracast is supposed to deliver higher quality audio with lower latency. The function seems to be based on the achievements of LE Audio, which promises better sound quality with lower power consumption thanks to the LC3 codec. However, we haven't yet been able to test whether the LC3 really makes an audible difference in Bluetooth headphones, as neither LE Audio nor the LC3 are currently widely used. With current ear test winner Sony WF-1000XM5, for example, you can only use the LC3 so far Use with existing Xperia mobile phones.

Auracast for large parties

While Bluetooth headphones are all about private, interference-free listening, Auracast seems to be aiming for maximum noise reduction when it comes to Bluetooth speakers. At least that's what ads at the CES trade show in January 2024 suggested, where Auracast was one of the unexpected trend topics.

JBL has announced that Auracast will be used in the successor to the Xtreme 3. Thanks to this technology, the Xtreme 4 can be connected to several other speakers in order to play as a large unit, as well as being able to play with another speaker in a stereo system.

The functionality isn't explained in more detail and we haven't been able to test the Xtreme 4 yet. However, it looks like JBL will be replacing both the Bluetooth True Wireless Stereo (TWS) and JBL PartyBoost features. Both functions are used to either use two speakers as a stereo pair, or, in the case of PartyBoost, to allow up to 99 compatible JBL speakers to play simultaneously. Hopefully we can verify this in the Xtreme 4 test.

Auracast: This is what you need to be ready for the new world of Bluetooth

There's one catch: In order to be able to use Auracast, all devices involved must support the technology. This includes both the intermediary device, usually your cell phone, and the receiving device, i.e. headphones or speakers. Of course, the corresponding transmitters must first be installed in bars, airports and waiting rooms.

Even if the station is available and your devices support LE Audio, it doesn't mean you can listen to it. Just as LE Audio is not a mandatory part of Bluetooth versions 5.2 and 5.3, Auracast does not need to be part of LE Audio. Therefore, when purchasing, you should make sure that Auracast is explicitly supported.

Fortunately, it appears that Auracast can be pushed to headphones and speakers via a software upgrade. So it may not be necessary to buy new hardware at all. However, the Bluetooth SIG itself appears here Don't be completely sure. In principle, it is possible to update Auracast, but this depends on the Bluetooth functionality already available in the device – and of course on whether the manufacturer considers Auracast important or not.

Android and Qualcomm are just getting started

However, Auracast is already present in Android 13 and 14 as well as in the latest Qualcomm chipsets, which are already integrated into the first headphones and mobile phones. Apple is currently holding back. If you buy the latest Android devices, you at least have a chance to be prepared for when the first TVs are equipped with Auracast channels. Since the requirements for Auracast are Bluetooth 5.2 or higher and the Public Broadcast Profile (PBP) specified in the LE audio standard, you can also keep an eye on this when retooling.