Key Takeaways:
- Wi-Fi audio assistive listening systems (ALS) use wireless networks to deliver sound directly to listeners. Audio can be captured from microphones, public address systems, televisions and other sources, then transmitted via the network to help people hear clearly in a variety of settings.
- Wi-Fi audio can broadcast on multiple channels at the same time. This allows venues to offer separate streams for different rooms, events, languages or types of content.
- Listeners typically connect to a Wi-Fi channel using their smartphone or a receiver provided by the venue. Depending on how the system is constructed, the channel may be accessed through an app, headphones, earbuds, or compatible assistive devices.
- The quality of the listening experience depends on factors such as network strength and coverage, smartphone compatibility, apps and receiver availability.
What is a Wi-Fi Audio Assistive Listening System?
Wi-Fi audio assistive listening systems use a wireless computer network to deliver audio from a microphone, public address system, television or other source to listeners. Depending on the system, listeners may use a dedicated Wi-Fi receiver or their own smartphone to receive the audio.
How does Wi-Fi audio work?
A Wi-Fi assistive listening system begins with an audio source. A Wi-Fi transmitter or network-connected audio processor receives the audio and converts it into a digital stream.
The audio stream is then delivered through a Wi-Fi network. A listener can access the stream typically using their smartphone or other supported device.
Some systems use a venue’s existing Wi-Fi infrastructure, while others may use a dedicated network established specifically for assistive listening. For example, a commercial Wi-Fi ALS may connect to the venue’s network and provide a dedicated audio stream that listeners select using an app. Dedicated receivers can also be supplied by the venue.
The network does not have to provide internet access for the basic transmission of audio. What matters is that the listener’s device can connect to the network carrying the audio stream. The specific configuration depends on the system.
Where Wi-Fi audio is used
Wi-Fi can be used in many of the same places as other assistive listening technologies. A theater might connect the system to its sound board so that patrons can listen to the performance through their own phones or through receivers supplied by the theater.
A university could use Wi-Fi audio in classrooms or lecture halls, allowing students to access the audio through a dedicated receiver or smartphone. A house of worship or conference center could similarly distribute audio to listeners throughout a room or facility.
Wi-Fi systems can also support more than one audio stream. Depending on the system, a venue might provide separate channels for different rooms, events, languages or types of content. Network-based systems can therefore be useful in facilities with multiple spaces or more complex audio requirements.
Some commercial systems are designed specifically for assistive listening and provide both dedicated receivers and smartphone access. For example, Williams AV’s WaveCAST system can deliver audio over a venue’s Wi-Fi network to dedicated receivers or smartphones using an app.
How does Wi-Fi differ from other transmission technologies?
Wi-Fi audio differs from traditional FM and infrared (IR) systems primarily in the way the signal is transported. FM sends the signal using radio-frequency transmission, while IR uses invisible light and generally requires line of sight. A hearing loop uses a magnetic field that can be received directly by a compatible telecoil.
Wi-Fi instead packages the audio as digital information and sends it over a network. This can make Wi-Fi systems flexible in large or multi-room facilities because the audio can be distributed wherever the network provides appropriate coverage.
Wi-Fi audio is also different from Auracast broadcast audio, which uses Bluetooth Low Energy rather than Wi-Fi. Auracast can transmit directly to compatible hearing aids, cochlear implants, earbuds, and headphones without requiring a traditional Wi-Fi network. Wi-Fi and Auracast are therefore separate transmission technologies, even though both can be used to provide wireless assistive listening.
Another difference is the potential role of a smartphone. With some Wi-Fi systems, the listener does not need a venue-specific receiver. The listener can use a smartphone to access the audio stream and then listen through headphones, earbuds or a compatible hearing device. Other Wi-Fi systems provide dedicated receivers for people who do not want to use a smartphone or whose phone is not compatible.
Using a smartphone can introduce additional steps compared to a hearing loop, where a listener with a telecoil-equipped hearing aid may simply select the telecoil setting. The listener may need to connect to the appropriate Wi-Fi network (which may cause a loss of access to the internet), download and open an app, select the correct audio channel and connect headphones or a hearing device. The exact process varies by system.
Because Wi-Fi ALS are network-based, the availability and stability of a compatible network, receiver, app and listening accessory can all affect the user experience. Some Wi-Fi users may experience significant latency—delayed audio streaming that may cause an echo effect or appear out-of-sync with the speaker’s or performer’s lip movements.
What equipment does a listener need?
The equipment required depends on how the venue has implemented its Wi-Fi system. A listener may use a dedicated Wi-Fi receiver supplied by the venue. The receiver may have a headphone output or may connect wirelessly to headphones or earbuds.
Alternatively, the listener may use a smartphone with the appropriate app or software. Audio can then be heard through wired headphones, Bluetooth headphones or earbuds or another compatible listening device.
Wi-Fi audio provides another way to deliver the same basic benefit as other assistive listening systems: moving the desired sound from the source to the listener while reducing the effects of distance, background noise and reverberation.
FAQs
Wi-Fi audio is an assistive listening technology that uses a wireless network to transmit sound from an audio source directly to a listener’s compatible device.
A Wi-Fi audio system converts sound into a digital audio stream and delivers it through a Wi-Fi network. Listeners connect to the network using a smartphone, dedicated receiver or other compatible device, then select the audio stream they want to hear. Depending on the system, the network may be part of the venue’s existing Wi-Fi infrastructure or a dedicated network created specifically for assistive listening.
Wi-Fi audio can be used in many public settings, including theaters, lecture halls, houses of worship, conference centers and other venues where people may benefit from clearer access to sound. Some systems can also support multiple rooms, events or language channels within the same facility.
Equipment needs vary based on the specifics of the venue’s ALS. Some venues provide dedicated Wi-Fi receivers, while others allow listeners to use their own smartphones with a compatible app. The audio is then passed to the listener’s headphones, earbuds or other listening device, which is not always the same as the device receiving the audio stream.
The main difference is how the audio signal is transmitted. Hearing loops use magnetic fields, FM systems use radio frequencies, IR systems use light and Auracast uses Bluetooth Low Energy. Wi-Fi audio transmits sound as information over a digital network.
In many Wi-Fi audio systems, yes. Listeners may be able to connect to the venue’s network, open a dedicated app and stream through headphones, earbuds or compatible hearing devices. Some venues also offer dedicated receivers for people who prefer not to use a smartphone.
The user experience varies by system. Some systems may require connecting to a Wi-Fi network, opening an app and selecting an audio channel before listening. Network coverage, device compatibility and available equipment can all affect access to the audio stream, sometimes causing latency (delay) issues.