Hearing clearly is something we take for granted daily but many rely on assistance from hearing aids and personal listening devices. In fact, according to a research article from the National Institute on Deafness and Other Communication Disorders ("Quick Statistics About Hearing" March 25, 2021), "About 2 to 3 out of every 1,000 children in the United States are born with a detectable level of hearing loss" and "Approximately 15% of American adults (37.5 million) aged 18 and over report some trouble hearing". Having assistive listening systems and devices available at your church, school or business can make all the difference for those that need it.
We're tackling all of your most asked questions about assistive listening technology, like defining what are assistive listening devices for the hearing impaired, what are some of the most commonly used types of assistive listening devices, where are assistive listening devices required, and more.
What is an Assistive Listening Device?
Assisted Listening Devices (ALDs), also known as Hearing Assistance Technologies (HATs) or auxiliary aids, can refer to any device, except hearing aids, that improves the ability to hear clearly and increases speech intelligibility. As assistive listening technology continues to expand, more of these devices are becoming available.
Assistive Listening Systems (ALSs) are ALDs or a collection of ALDs designed to help those that need auditory assistance in larger commercial venues to overcome the challenges of background noise, long distances, language interpretation, and hearing loss. ALSs are a convenient and economical solution that can help to stay compliant with Americans with Disabilities Act (ADA) assisted listening system requirements in public spaces.
How do Assistive Listening Systems work?
ALSs usually consist of a bodypack transmitter, a set of headphones with individual volume control, and a receiver that amplifies the audio signal being transmitted through a public address or commercial sound system. The sound goes directly to that person’s ear through the headphones, increasing the intelligibility of conversations and allowing audio to be better heard while not disturbing everyone else around because the sound is too loud.
Some listening systems such as tour guide systems may also have a microphone attached to the headset allowing for two-way communication. This means not only can the person hear better, but they can speak more clearly without having to shout. If you're in a large group, like a tour, just speak into the microphone, the person on the other end, either the group leader or oftentimes the whole group can hear you.
Who can use Assistive Listening Systems?
Assisted listening can be helpful for those with all degrees of hearing loss, as well as those with voice, speech, or language disorders, or anyone who wants to hear better, louder, and communicate more effectively. ALDs and ALSs can also be used in conjunction with hearing aids or other hearing devices like cochlear implants to extend the reach and increase the effectiveness.
Where are Assistive Listening Devices required?
People can use ALSs in a large variety of applications but the Americans with Disabilities Act (ADA) requires some specific public areas to provide assisted listening systems and devices. Some of these spaces include classrooms for students, public meeting rooms, government buildings, courtrooms, legislative chambers, theaters, auditoriums, concert halls, amphitheaters, stadiums, and convention centers. Other locations that may also use ALSs are churches, houses of worship, factories, warehouse complexes, industrial plants, work zones, places that do tours like museums and zoos, as well as other language interpretation or high noise environments.
Where required, there should be a sign that says ADA with the universal hearing symbol and someone nearby who can give out assisted listening devices. If a brand has had their systems reviewed to be certified as ADA compliant assistive listening device systems they will usually show this sign with their product as well. If you ever have a question about it, you can just ask, is this ADA approved? One of our Sales Engineers will be glad to help.
There are several types of Assistive Listening Devices (ALDs) and Assistive Listening Systems (ALSs) out there. Most great microphone manufacturers will typically have their version of an assisted listening system. This includes brands like Sennheiser, Shure, TOA Electronics, Listen Technologies, Williams Sound, Anchor Audio, and more. The most commonly used listening assistance devices are hearing loop systems, frequency-modulated (FM) systems, radio frequency (RF) systems, and infrared (IR) assistive listening devices.
Assisted Listening Hearing Loop Systems
A hearing loop or induction loop assistive listening system basically uses a piece of wire that is placed along the baseboards of the floor all the way around the room. This takes the sound and amplifies it via an electromagnetic signal and then transmits it to a receiver usually worn as headphones or a headset, which allows you to move more freely inside the space.
Since the sound signal goes directly to the receiver, Hearing Loop Systems can effectively reduce background noise. These systems are usually found in theaters and conference centers. Another advantage to the Hearing Loop System is that there aren’t the normal distance limitations found with other types of systems, as long as the receiver is within that loop, it’s receiving signal.
Radio Frequency (RF) or Frequency-Modulated (FM) Assistive Listening Devices
These are probably the most popular systems on the market because they work well with hearing aids. FM and RF assistive listening systems are wireless hearing devices that transmit sounds using radio broadcasting technology. The speaker wears a small microphone that’s connected to a transmitter. Most hearing aids have a designated frequency inside that allows them to connect directly into these types of systems. The hearing-impaired individual can also wear a bodypack receiver that’s tuned to the specific radio frequency or channel.
FM and RF listening systems are often used in classrooms or educational settings as assistive listening devices for students, as well as tour guide systems and language interpretation systems. Some systems can transmit signals up to 300 or even500 feet and as long as they are within that space, they will receive the signal and get amplified sound.
However, some issues can occur when using radio signals because, unlike using a loop wire where it's restricted to that space, a radio signal can pass through walls. This can allow for the possibility of a lot of interference from other channels nearby, such as TV broadcasters and even cell phones, reducing the efficiency of your system.
Infrared (IR) Assisted Listening Systems
The last system type is infrared listening systems. These utilize light-based technology by having an infrared transmitter and an infrared listening receiver that are in the line of sight of each other. The transmitter and receiver have to see each other for them to work effectively. The IR transmitter converts sound into light and then sends that invisible infrared light within 360 degrees ofo the receiver. The receiver then converts the light signal back into sound. Infrared systems work well in smaller spaces but are not recommended in spaces with large groups because anything that gets in front of the light signal is going to interfere with the transmission.
You may consider using an infrared hearing system in applications that require confidentiality or in buildings where competing signals may be a problem. This is because infrared signals are not able to pass through walls and therefore they can’t easily be picked up from outside the room. They are often used in courtrooms and places of entertainment.
It's important to note that infrared systems cannot be used in places that are too bright. Too much light can interfere with the signal so this may not be the best system for rooms with lots of glass or windows.
If you have any questions about assistive listening systems and devices or any other audio needs, reach out to us at (888) 256-4112 or email [email protected] and we'll be happy to help.
