Auracast™, a powerful feature of Bluetooth LE Audio, allows a single audio broadcast to be received by an unlimited number of nearby devices — no pairing required. This blog explores how many Auracast receivers can coexist in the same space, how the technology works in public environments like airports or gyms, and why it’s a breakthrough for scalable, synchronized wireless audio. Whether you're building next-gen audio products or just curious about the future of Bluetooth, this post explains everything you need to know.

Bluetooth LE Audio is transforming wireless sound with better quality, lower power usage, and exciting new features like Broadcast Audio and multi-stream playback. At the heart of this revolution is CSIP (Coordinated Set Identification Profile)—a key technology enabling seamless coordination between multiple audio devices. CSIP allows a group of devices, such as true wireless earbuds, to function as one logical unit. This means your phone can discover, pair, and manage them together. Whether you're adjusting volume, playing music, or taking calls, CSIP ensures everything stays in sync across all devices in the set. The magic happens through a Set Identity Resolving Key (SIRK), which securely identifies and links devices in a group. Each device advertises itself as a set member, and your phone can recognize and control them as one.