Why Auracast^™ Broadcast Audio
Needs to Coexist With Current
Assistive Listening TechnologiesAuracast™ ブロードキャスト オーディオと現行の聴覚補助技術との共存が必要な理由とは

Assistive Listening Technology in Deployment Today

Hearing Loops: With hearing loops, audio is transmitted from a nearby source, such as a presenter’s microphone in a conference hall, to a hearing loop driver. The driver converts sound to a magnetic field via a wire loop that is placed around a specific room or hearing space. The sound is picked up by the telecoil built into a hearing instrument or cochlear implant, converting it back into an audio signal within the device.

FM/Radio: For FM/radio, audio is transmitted from a source system via an FM radio frequency transmitter to a separate receiver worn by the listener. Audio from the receiver is heard by the listener using headphones or a telecoil coupler via a personal inductive neck loop. The frequency range for FM receivers can vary by location and operates in regional license-free frequency bands.

Infrared: With infrared (IR), audio is transmitted from a source device (e.g., a sound system) to an IR transmitter with a modulator that sends the audio signal into an area flooded with infrared light. This signal is picked up by a compatible receiver that is predominately in line of sight to the IR transmitter. Audio from the receiver is heard by the listener using headphones or a telecoil coupler supported by a personal inductive neck loop worn by the listener. Infrared may not be suited for outdoor locations or venues with lots of glass or glossy surfaces in sunlight.

For more on existing ALS solutions, check out this detailed comparison of available assistive listening technologies.

Auracast™ Broadcast Audio as an ALS

The various assistive listening technologies deployed in a multitude of public venues worldwide have fragmented the ALS market and led to inconsistent availability and varying user experiences. Auracast™ broadcast audio has the potential to solve many of these challenges. It is universal, highly reliable, and flexible while being relatively inexpensive to deploy and taking advantage of a user’s personalized equipment (e.g., earbuds, headphones, hearing aids, etc.). A low-impact alternative that benefits a wider range of visitors and experiences in public spaces, Auracast™ broadcast audio use cases and experiences will incentivize venues to install it, bringing greater accessibility to more hearing instrument users. Users receive sound directly in their hearing aids, regardless of the brand, and without the need for accessories.

Learn more about Auracast™ broadcast audio use cases.

How It Works

A single, centrally located Auracast™ transmitter (e.g., smartphone, tablet, PC, TV, PA system, etc.) can broadcast audio to an unlimited number of in-range Auracast™ receivers. Receivers do not need to be in a specific enabled section or in line of sight to the transmitter. The nearby Auracast™ transmitter will broadcast a signal, notifying Auracast™ receivers and possible assistants (e.g., smartphones, smart watches, etc.) that there is an Auracast™ transmission available in the area.  

Auracast™ assistants scan for these signals and provide a user interface (UI) to enable users to select an Auracast™ transmission, similar to the UI commonly used to connect to Wi-Fi networks in public spaces. A broadcast assistant is not required in all instances; however, it will be one of the most common methods to find and join an Aurcacast™ broadcast. Once an Auracast™ transmission is selected, the Auracast™ assistant informs the Auracast™ receiver (e.g., headphone, earbud, hearing aid, etc.) how to join the Auracast™ transmission. For users who are unable or reluctant to use a smartphone, solutions will be made available that allow an Auracast™ broadcast to be received without needing a smartphone. However, for situations where many relevant audio signals are available or a passcode is required for encrypted transmissions, the use of an assistant device will greatly facilitate the process of connecting to the desired signal.

Industry Recommendations and the Importance of Coexistence

There are few concerns regarding the promised efficacy of Auracast™ broadcast audio, and many in the hearing industry recognize its potential as a next-generation ALS. But some industry experts recommend manufacturers implement Auracast™ broadcast audio while maintaining existing telecoil capabilities and loop installations until Auracast™ broadcast audio has gained mass adoption in the market. If telecoil was immediately removed from new hearing instruments, and if existing hearing loop manufacturers immediately stopped supporting hearing loop implementations in favor of Auracast™ systems, that could have a detrimental effect, isolating hearing instrument users that currently rely on telecoil.

There is also a worry that new phones may not work with older models of hearing instruments that are not compatible. As Auracast™ broadcast audio gains adoption, new devices must carefully consider all of the applications of the existing hearing loop usage, much of which is embedded in standards and currently mandated.

Recently, the International Federation of Hard of Hearing People (IFHOH) published a declaration praising the Bluetooth SIG for its work with the European Hearing Instrument Manufactures Association (EHIMA) in creating Auracast™ broadcast audio, “a wireless universal technology…that promises to assist hard of hearing individuals to hear better in venues where hearing aids and cochlear implants are insufficient to function.”

However, the IFHOH also stressed the importance of coexistence between Auracast™ broadcast audio and existing assistive listening technologies. “IFHOH foresees a world where FM, IR, and hearing loop systems (including those found in taxis, ticket counters, airports, theatres, etc.) will function for the foreseeable future alongside Auracast™ systems. Therefore, all assistive listening systems, hearing aids, and cochlear implants need to be Auracast™ broadcast audio + telecoil compatible.”

There will be a significant period of overlap between both technologies before Auracast™ broadcast audio reaches full market potential, which could take years, maybe even a decade, to realize. Until the availability of Auracast™ broadcast audio (within the end-user community) exceeds the availability of other systems (e.g., telecoils), it should be offered as an additional ALS option.

Standardizing Auracast™ Broadcast Audio as an ALS

Industry experts agree that an additional international standard for assistive listening supporting the installation of Auracast™ broadcast audio in public spaces, similar to IEC60118-4 for hearing loops, will be essential to ensuring consistency and quality of service worldwide. Requirements may include location deployment guidelines, such as setting appropriate audio levels for the hearing aid, frequency response levels, signal-to-noise limits, dynamic range limitations, and ensuring end-to-end latency is minimized and below defined limits. The sooner a strong, clear standard for the installation of Auracast™ broadcast audio is in place, the sooner it will benefit the industry and the end user.

The Bluetooth SIG provided some guidance to transmitter manufacturers and installers with the publication of the Auracast™ Simple Transmitter Best Practices Guide. 

The Future of Assistive Listening Is Coexistence

There is no question a functioning ALS in public locations is an important factor in maintaining appropriate hearing health of individuals with hearing loss. Auracast™ broadcast audio is an easy, cost-effective option to deploy. It is simple to use, and it is reliable. But complete market saturation for universal audio accessibility in public spaces will take some time. The Bluetooth SIG agrees that the coexistence of Auracast™ broadcast audio with existing assistive listening technology will be essential to enhancing audio experiences for hearing instrument users and offering them greater options for accessibility in public locations.