How to build an Auracast assistant: technical overview, version 1.0

Summary

The SIG's design guide for the phone apps, watches and remotes that find broadcasts and tell hearing aids or earbuds which one to join.

Key findings

• Hearing aids and earbuds may receive less well than the assistant, so an assistant can list broadcasts that the listener's devices cannot pick up; whether to show only transmitters above a signal-strength threshold is left to each app.
• If a broadcast announces no 16 or 24 kHz stream and the listener's device cannot decode 48 kHz, the listener may need to ask for a Standard Quality stream to be turned on.
• No method is specified for an assistant to obtain a Broadcast Code; the guide lists manual entry of a printed code, QR codes or NFC tags, and codes passed from a built-in transmitter such as a TV.
• A transmitter cannot change its Broadcast Code during a broadcast; a new code means stopping and restarting the broadcast.
• Sections 2.1 and 4.3 describe delegating power-hungry discovery from small-battery hearing devices to an assistant, which may scan on request rather than continuously to conserve its own battery. They report no measured battery-life penalty.
• Sections 4.3.3-4.5 describe examining subgroup content (including language), codec settings and channel positions, maintaining a list and requesting reception of selected BISes. Section 2.2 leaves interface design to manufacturers; sections 4.3.1 and 4.3.3 leave filtering policies to implementations.

Limits

Design guidance for app and device makers. Although written after the Broadcast Audio URI specification was adopted in 2024, it describes the format for codes in QR codes as not yet standardised.

Read the original

www.bluetooth.com/wp-content/uploads/2024/05/2403_How_To_Auracast_Assistant.pdf

Link checked 13 October 2026. We link to the original and do not host copies.

Cited in

• Which hearing devices can receive which systems?Open
• What signal strength is enough at the farthest seat?Open
• How do listeners find and join the right broadcast?Open
• Open or protected: when should a venue broadcast need a code?Open
• What works in courtrooms, council chambers and other meeting rooms where speech must be heard by all and kept in the room?Partly answered
• Can one venue offer several Auracast streams at once (languages, audio description, a mix for hearing aids), and how do listeners choose?Partly answered

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