Bluetooth Low Energy (LE) Audio is a new standard for low-power audio streaming via Bluetooth. The LE is used, until then, for data transfers that do not require as much power and speed, which normally occurs in IoT and wearable devices. However, the Bluetooth SIG (Bluetooth Special Interest Group), the organization responsible for overseeing the development of Bluetooth standards and performing the licensing of technologies and brands that market products with support, presented a series of new features for Bluetooth Low Energy during CES. 2022. And that’s what we’re going to talk about in this article.
LC3 codec
One of the great novelties of Bluetooth LE Audio is the new LC3 codec, or Low Complexity Communications Codec. For starters, a codec basically compresses the audio to whatever size it needs for streaming, i.e. being transmitted over the Bluetooth connection. According to the developers, this new codec puts the bitrate at lower levels than the sub-band codec (SBC), but ensures that the audio is sent flawlessly over Bluetooth LE even in conditions of heavy radio wave interference. .
The LC3 codec has a bitrate variation ranging from 160kbps to 345kbps, while the SBC covers the range from 240kbps to 345kbps. Theoretically, the SBC would still be superior when it comes to transmitting higher audio quality, but according to Manfred Lutzky of Fraunhofer IIS, several sound tests prove that the LC3 will change the Bluetooth standard, with improvements in audio quality reaching 50%. The SBC codec included in Classic Audio has been on the market since the first version of Bluetooth technology and is used for high-speed data transfers, which consume more energy. It is worth mentioning that the LE standard has been around since 2009, but the difference is that there was no audio support.
Additionally, Bluetooth LE audio using the LC3 codec is about twice as energy efficient as Bluetooth audio using the existing sub-band codec (SBC). With the change, then, the audio increases in quality and decreases in energy consumption. This makes two main things possible for devices that will implement the technology in the future: first, the devices will be able to be smaller without sacrificing runtime and, second, battery life can be significantly improved without additional size or weight.
Multi-Stream
In general, we can say that the big difference between Bluetooth LE audio and Classic Bluetooth is that the former is a multi-stream technology. From that, we have new features, as well as improved voice control and voice assistant support.
An example of these novelties is the possibility of connect a single wireless headset to different devices of the same type. In this way, future headphones where the left and right sides have independent connections will benefit from the technology. Most devices these days work with a Bluetooth connection to one headset and the other works as a “slave”, also facing latency issues.
Furthermore, it will be possible Connect to an unlimited number of Bluetooth devices within range of a single audio source. Due to the way the standard is designed, the source audio will not be interrupted when you connect a new device, and the user will be able to listen to the same song or podcast, for example, with a friend on different headphones in sync.
Finally, a third feature of LE Audio is the Bluetooth Broadcast. To explain it, it is good to give an example: imagine that you are in a restaurant with different screens showing different programs to your customers. Normally, you wouldn’t be able to hear what’s happening on the screen you’re interested in, but with Bluetooth Broadcast it would be possible to connect your headphones to that audio stream with several people at the same time, even in different languages. The applications will be diverse and the great asset is that this will arrive natively within the standard, not as a specific property that depends on some programmer to make a system.
The new LE Audio technology will be introduced in Bluetooth devices that support the next generation of wireless connection, version 5.2. We know that general adoption of the standard may still take a while, but the components needed by developers to add support in their future devices, headsets and hearing aids are theoretically already available. So, we just have to wait until the devices supporting Bluetooth 5.2 hit the market for good to start seeing the improvements and advantages that Bluetooth LE audio can provide.