Technology
What is Bluetooth LE Audio?
For about twenty years, Bluetooth headphones have worked in much the same way. LE Audio is the next generation: a new codec, support for hearing aids, and Auracast, which lets one phone or TV send sound to any number of listeners.
In short. LE Audio carries sound over Bluetooth Low Energy instead of the older Classic Bluetooth. Its new codec, LC3, did better than the old SBC codec in the Bluetooth SIG’s listening tests even at half the bit rate, which saves power. It adds support for hearing aids, several synchronised streams for wireless earbuds, and Auracast, which broadcasts sound to an unlimited number of listeners. The device that sends and the one that listens both have to support it.
Classic Audio and LE Audio
Until now, Bluetooth headphones have mostly used Classic Audio, with a codec called SBC. LE Audio is built on Bluetooth Low Energy, the low-power side of Bluetooth that fitness bands and smart rings already use for their data. The Bluetooth SIG, the industry body behind the standard, describes it as improving Bluetooth audio, adding support for hearing aids and introducing Auracast broadcast audio.
LC3: more sound per bit
A codec squeezes sound into fewer bits for the radio and unpacks it at the other end. LE Audio’s codec is LC3, the Low Complexity Communications Codec. According to the Bluetooth SIG, extensive listening tests showed that LC3 improves on SBC’s audio quality even at a 50% lower bit rate. Fewer bits mean less radio time and less power, which a maker can spend on longer battery life or a smaller battery.
Several streams at once
Multi-stream audio lets one source, such as a phone, send several independent, synchronised streams to one or more devices. The SIG presents it as a way to improve truly wireless earbuds, where the left and the right earbud each need their own sound, in step.
Hearing aids
LE Audio adds support for hearing aids, so that they can get Bluetooth audio from phones, TVs and other sources through the same standard as earbuds. Engineers from hearing instrument makers contributed to it.
Auracast: one sender, any number of listeners
Auracast broadcast audio lets one source send one or more audio streams to an unlimited number of nearby devices. The Bluetooth SIG describes uses such as:
- Sharing. Friends listening to the same phone, each on their own earbuds.
- Silent screens. Hearing a muted TV in a public place, such as a gym or an airport, on your own earbuds.
- Assistive listening. Theatres, lecture halls and places of worship sending sound straight to hearing aids and earbuds. The SIG expects Auracast to become the next generation of assistive listening technology.
Joining is meant to be simple: pick a broadcast from a list, much as you pick a Wi-Fi network, or scan a QR code.
What you need
Both ends have to support it: the phone, laptop or TV that sends, and the earbuds or hearing aids that receive. Look for LE Audio, LC3 or Auracast in the specifications. Devices without it keep working the classic way.
Why it matters for small wearables
Wearables have tiny batteries, so audio that costs less power matters even more for them than for a phone. Lychnos Ring is designed to play its answers through earbuds that support Bluetooth LE Audio, or through its own small speaker when you raise it to your ear; its microphone is on only while you hold the button. It is in development: the AI ring.
Sources, read 4 November 2026: Bluetooth SIG, LE Audio and Auracast broadcast audio. Auracast is a trademark of the Bluetooth SIG. General information.
Questions
What is the difference between Bluetooth LE Audio and Classic Audio?
Classic Audio is the older way Bluetooth carries sound, with the SBC codec. LE Audio runs on Bluetooth Low Energy, uses the newer LC3 codec, adds support for hearing aids, and allows Auracast broadcasts to any number of listeners.
Do my earbuds support LE Audio?
Check the specifications of both the earbuds and the phone or other source for LE Audio or LC3: both ends need it. For broadcasts, look for the Auracast name.