Best Practices for Using
a Standalone Auracast™
Transmitter

2.1 Auracast^TM Transmitter Types

Auracast™ transmitters are generally classified in two categories:

Public Auracast^TM transmitter: A Bluetooth^® product capable of transmitting a PBP-compliant standard quality audio broadcast and which is intended for deployment within a public venue, such as commercial public address (PA) systems, televisions, and audio streamers. When set to transmit, the default configuration for a public Auracast^TM transmitter must include a Standard Quality Broadcast Audio stream.

Personal Auracast^TM transmitter: A Bluetooth^® product capable of transmitting a PBP-compliant audio broadcast and which is intended for personal use such as a smartphone, tablet, laptop, PC, home television, or home audio streamer. All personal Auracast™ transmitters are required to be able to transmit a Standard Quality Public Broadcast Audio stream but may default to transmitting a High Quality Public Broadcast Audio stream.

2.2 Physical Implementations

Auracast^TM transmitters may be installed by people with a wide range of technical knowledge, from novice to expert. Manufacturers should design Auracast^TM broadcast audio products with an understanding of the likely installer so that the end-user experience is the same for anyone listening to an Auracast^TM broadcast. A generic out-of-the-box configuration should include enough information to provide a consistent user experience for the intended audience with the ability to tailor it with minimal technical knowledge.

The physical form factor of an Auracast^TM transmitter is independent from its function. The Auracast^TM transmitter might be a dongle that is plugged into an audio source device, a small box connected with a cable to the output jack of a sound system (as shown in Figure 3.1), or it might be part of a System-on-Chip (SoC) within a consumer electronics device, such as a smartphone, television, or PC.

2.3 Support for Standard Quality Public Broadcast Audio

All Auracast™ transmitters are required to be able to transmit broadcast audio at 16kHz or 24kHz using the LC3 codec [2] [8], which is known as Standard Quality Public Broadcast Audio in the underlying Public Broadcast Profile (PBP) specification. In addition to supporting standard quality, support for 48kHz LC3 audio is permitted, which is known as High Quality Public Broadcast Audio.

As identified by the use of Auracast Trademarks in the Brand Guide for Bluetooth Trademarks [8], for all transmitters, the product must be configurable by the end user to broadcast a Standard Quality Public Broadcast Audio stream. Additionally, if the transmitter is marketed for use within a public location (where “public location” means any public, private, or commercial venue, building, means of transport, or open space), the product’s default setting when configuring the product to transmit an Auracast™ broadcast must be to broadcast a Standard Quality Public Broadcast Audio stream.

The intent of both of these requirements is to increase the likelihood that all products capable of receiving Auracast™ broadcast audio will be able to do so, as some hearing aids may only receive Auracast™ broadcast audio that is configured as a Standard Quality Public Broadcast Audio stream. In practice, what this means is, to support the broadest portfolio of receiver devices in a public location, a Standard Quality

Public Broadcast Audio stream must be made available for all audio content provided through Auracast™ broadcast audio by the location. Because the transmitted standard quality audio stream packets are smaller, they will typically provide slightly better range and robustness to interference compared to high-quality packets.

Personal Auracast™ transmitters may default to transmitting a high-quality audio stream but are required to allow a user to select transmission of a standard-quality audio stream [8]. If a standard-quality audio stream is selected for transmission, the decision whether the standard-quality audio stream is transmitted concurrently with a high-quality audio stream, or is transmitted instead of a high-quality audio stream, is determined by the manufacturer.