Introducing LE Audio
Q: What is LE Audio?
A: LE Audio is the next generation of Bluetooth audio. Building on 20 years of innovation, LE Audio will enhance the performance of Bluetooth audio, add support for hearing aids, and introduce Auracast™ broadcast audio, an innovative new Bluetooth capability with the potential to once again change the way we experience audio and connect with the world around us.
Q: What does ‘LE’ stand for in ‘LE Audio’?
A: LE stands for Low Energy, as LE Audio operates on the Bluetooth Low Energy radio.
Q: What is the minimum version of Bluetooth Core Specification that LE Audio requires?
A: LE Audio relies on a new core feature introduced in version 5.2 of the Bluetooth Core Specification. Products that support LE Audio will also support that feature, which is called LE Isochronous Channels and brings an isochronous data transport option to the Bluetooth Low Energy radio.
Classic Audio and LE Audio
Q: Are new headphones and devices required to use LE Audio? Is it backward compatible?
A: Consumers will need to check with the product manufacturer to understand whether an existing product is upgradable. It is possible that existing Classic Audio products could be compatible with LE Audio source products. However, products can be developed to support both Classic Audio and LE Audio, and it is expected that many products that support LE Audio will continue to support Classic Audio.
Q: Can Classic Audio and LE Audio work together in the same device?
A: Yes. The LE Audio specifications will allow for products to support both Classic Audio and LE Audio, and many are expected to do so.
Q: Will existing Classic Audio sink products be compatible with LE Audio source products?
A: No. Sinks and sources must use the same approach. However, as products can be developed to support both Classic Audio and LE Audio, it is expected that many products that support LE Audio will continue to support Classic Audio.
Q: Will LE Audio require all devices to also support Classic Audio?
A: Support for Classic Audio will not be mandatory for LE Audio devices. It will be up to product developers to decide which versions of Bluetooth audio their solution supports.
Auracast™ Broadcast Audio
Q: What is broadcast audio?
A: While Bluetooth technology supports multiple communication topologies for data transfer, including point-to-point, broadcast and mesh, it has only supported point-to-point communications for audio. LE Audio changes that by adding broadcast audio to Bluetooth technology, a new feature that enables an audio source device to broadcast an audio stream to an unlimited number of Bluetooth audio sink devices. Bluetooth audio broadcasts can be open, allowing any in-range sink device to participate, or closed, where only those sink devices with the correct passkey can participate. Broadcast audio opens significant new opportunities for innovation, including the enablement of a powerful new capability, Auracast™ broadcast audio.
Q: What is Auracast™ broadcast audio?
A: Auracast™ broadcast audio is a set of defined configurations of Bluetooth® broadcast audio which are specified within the Public Broadcast Profile (PBP) specification that enables new, globally interoperable audio experiences for consumers that will enhance the way they engage with others and the world around them.
Auracast™ is also a registered trademark of Bluetooth SIG, Inc. that developers can be licensed to use in association with products that complete the Bluetooth Qualification Process and meet the additional requirements of use as detailed in the Brand Guide for Bluetooth Trademarks. Public locations that successfully complete Auracast™ location registration may also be licensed to use the trademark for promotional purposes.
Q: What do you propose as the method for scanning for and selecting a broadcast audio stream on a pair of headphones? Would it be via an APP on your phone/phone connects to the audio stream and relays it to the headphones?
A: The LE Audio specifications are planning to support multiple approaches for scanning and selecting Auracast™ broadcast audio streams, including the ability for a 3rd party device, such as a smartphone, to facilitate such a process.
Q: Can each Auracast™ receiver control its volume independently?
A: Yes, each Auracast™ receiver can control its volume independently.
Bluetooth LE Audio for Hearing Aids
Q: How is LE Audio different from today’s hearing aids that are Bluetooth enabled?
A: Due to its ability to provide high quality audio at significantly lower power, as well as support for multi-stream and broadcast audio capabilities, LE Audio will enable Bluetooth to be integrated into a significantly larger percentage of hearing aids.
Q: Is additional labeling for hearing aids contemplated?
A. The hearing aid industry is currently working to understand how best to make users aware of the new features, particularly for Auracast™ broadcast audio, which will supplement and possibly eventually replace telecoil connectivity
Q: What is Multi-Stream Audio?
A: Multi-Stream Audio, a new feature included in LE Audio, enables the transmission of multiple, independent, synchronized audio streams between an audio source device and one or more audio sink devices. Using this new feature, developers can improve the performance of truly wireless earbuds, including a better stereo imaging experience, more seamless voice control services, and smoother switching between multiple audio source devices, such as when a headset is simultaneously connected to both a smartphone and laptop.
Q: For the Multi-Stream Audio feature, how many simultaneous audio streams are possible? Is the number different when using Broadcast Audio?
A: The number of simultaneous streams will depend on the application and targeted audio quality. We are planning to provide more information on this subject when the LE Audio specifications are released.
Q: When LE Audio is used to support truly wireless earbuds, will a phone see and pair with two Bluetooth addresses?
A: LE Audio introduces the concept of coordinated sets of devices. It will be up to manufacturers how they expose those through their user interfaces.
Q: What is the new audio codec?
A: LE Audio includes a new high-quality, low-power audio codec called LC3, or Low Complexity Communications Codec. Providing high quality even at low data rates, LC3 will bring tremendous flexibility to developers, allowing them to make better design tradeoffs between key product attributes such as audio quality and power consumption.
Q: Can you quantify the expected reduction in power consumption over Classic Audio?
A: Power reductions will depend on implementation and product usage. Listening tests have shown that the LC3 codec can provide higher audio quality than the current SBC codec when operating at that same bit rate (and same power consumption), as well as provide the same, or slightly better, audio quality as SBC at less than half the bit rate (half the power consumption).
As a result, product developers focused on providing the highest audio quality might choose to implement LC3 in a way that would provide higher audio quality than products today but with the same battery life. Other developers focused on battery life might choose to implement the LC3 codec to provide longer battery life – up to double – than products today but deliver the same audio quality. Or they may choose something in between, where the product would provide slightly better audio quality than today as well as up to a 50 percent increase in battery life.
Q: Who is the owner of the LC3 codec IP?
A: While the name “LC3” may be common with other uses outside Bluetooth, the LC3 codec for use within Bluetooth will be specified in a Bluetooth specification. The intention of the Bluetooth SIG is that technology specified in the Bluetooth specifications is covered by the Bluetooth PCLA.
Q: Are other codecs supported, or only LC3?
A: While support for LC3 will be mandatory, LE Audio will allow for the addition of optional codecs as well as the use of custom codecs.
Q: Can the new LC3 codec be used over Bluetooth Classic as a replacement to SBC, in a similar way to how AptX is used?
A: While LC3 is being introduced with LE Audio, and support is mandatory for all LE Audio products, it may also be added as an optional codec for Classic Audio in the future.