Assistive Listening Devices to the Rescue!
A Primer to Help You Get Started
© February 2008 by Neil Bauman, Ph.D.
Hard of hearing people often lament, “Hearing aids don't work well for me,
particularly in noisy places such as while driving in the car or talking in
noisy restaurants.” They then ask, “What can I do in order to better hear my
spouse and friends under such conditions? Being unable to communicate freely is
putting a strain on my marriage and my friendships.”
Unfortunately, when most people lose some of their hearing, they are told to get
hearing aids, as though hearing aids were the whole answer to hearing loss. The
result is they become disillusioned with their hearing aids.
You see, hearing aids are not perfect, and in some listening situations such as
in noisy places, or when you are at some distance from the speaker, they can be
almost useless!
That’s where Assistive Listening Devices come in. They can largely overcome
these two main limitations of hearing aids (noise and distance), and thus help
you hear awesomely better.
Picture this. You have your hearing aids on and are sitting in your living room
trying to listen to your favorite TV show. Only one problem. Your young
grandkids are playing and shrieking right at your feet. Your hearing aids are
picking up and amplifying all their racket. Your frustration mounts as you miss
most of your program. Your hearing aids are just not helping you in this
situation.
Now picture this same scenario. The grandkids are making just as much noise by
your feet as before—but you sit there oblivious to their shrieks as you enjoy
your favorite TV program—hearing it clearly without any interference. The
difference is like night and day. That is what Assistive Listening Devices
coupled with your hearing aids can do for you. Sounds incredible, doesn’t
it?—but once you’ve tried it, you’ll know it’s true!
Generally you can use assistive devices with, or without, your hearing aids—but
teamed up with your hearing aids, they can make an awesome combination.
Benefits of ALDs
There are two major benefits of Assistive Listening Devices (ALDs).
First, ALDs can bring distant sounds close to your ears. When you use ALDs
properly, it sounds as if a person is talking directly into both of your ears at
the same time, and not from a distance. As a result, their speech sounds much
clearer—you understand more than you would with hearing aids alone. This is
because with ALDs you now hear more of the high-frequency sounds that give
speech much of its intelligence. Since these sounds are lost in the air with
increasing distance, your hearing aids don’t pick them up as the distance
increases. However, properly-used assistive devices do. This makes an enormous
difference to your understanding people talking.
Second, ALDs, when properly used, cut out most background noise since the
microphone is much closer to the speaker’s mouth than it is to the surrounding
background noise. For example, if you are in a meeting and the people around you
are coughing, talking, clinking dishes or rustling papers, your hearing aids
will pick this up, and you will have trouble understanding the speaker though
all this extraneous noise. With ALDs, you will only hear the sounds going into
the speaker’s microphone, not the disturbing noise around you.
Basic Kinds of Assistive Listening Devices
Assistive Listening Devices use various technologies to get the sound from the
speaker’s mouth to your ears. However, no technology gives significantly better
sound than the other—they all do the same thing—deliver beautiful, clear sound
directly to your ears.
Therefore, choose a technology based on your needs, what you can afford, what is
available to you, and what works best in the particular listening situation you
are in, and not on the quality of the sound since it is pretty much the same.
Here are the five technologies in current use today.
- Personal amplifiers
- FM systems
- Infra-red systems
- Induction Loop systems
- Bluetooth systems
Here’s a brief look at each of these in turn so you can see why you might choose
one over the other in any given situation.
1. Personal Amplifiers
Typically you would use a Personal Amplifier such as the
PockeTalker when you
are close to the speaker and are not moving around. For example, listening to
your spouse or friend when riding in a car, or conversing in a noisy restaurant.
You clip a lapel microphone to the person to whom you are conversing, plug it
into your personal amplifier, plug in a
neckloop (or
Music Links) and listen to
your partner via the t-coils in your hearing aids. This cuts out most of the
background noise.
The downside of such an arrangement is that your are wired together and thus are
not free to move around. However, in situations where you are both sitting down
that is not a problem. You can also use these devices to listen to your TV by
attaching the microphone of the device near the TV’s speaker and running the
microphone cord across the room to your PockeTalker. You can do the same if the
person you are talking to is sitting on the other side of the room. This is
typically the cheapest way to go. Cost is around $200.00 with the
lapel
microphone.
Read our article "Hear In Noise? You Bet You Can!
Here's How" to learn more of the benefits of using a personal amplifier such
as the PockeTalker.
2. FM Systems
FM systems use radio waves to transmit the sound from the speaker’s mouth to
your ears. Because there are no wires connecting you to the speaker, you are
free to move around, or sit at some distance from the speaker. For example, you
can typically be up to 150 feet away from the speaker and still hear just as
well as if the person was talking directly into your ears. Of course, this
requires the person speaking to cooperate and wear your FM
microphone/transmitter.
You can use FM systems even if you have to go into an adjacent room, or if you
are outside walking, or riding your bicycle with a friend. You will hear your
friend’s voice beautifully clear in your ears. One drawback of FM systems is
that they tend to be quite expensive—in the neighborhood of
$600.00 and up, although some are much
cheaper and come in around $200.00.
3. Infrared Systems
Infrared systems are similar to FM systems, except they use light waves instead
of radio waves to transmit the sound. Typically, infrared receivers are used in
meeting halls/theaters and for watching TV.
However, infrared systems are not as versatile as FM systems because of two
things. First, you cannot use them outside, or in a room with a lot of sunlight
streaming in—as the infrared component of the sun’s rays causes horrible
interference. So do many flat-screen TVs. Second, light waves travel in straight
lines. Thus your infrared receiver always has to be line-of-sight to the
speaker’s infrared transmitter (called an emitter). Therefore, if you turn away
from the TV, or go to the kitchen, you won’t hear anything until you return and
face the TV again (line of sight remember). Anything or anybody coming between
you and the emitter blocks the signal. I find these problems severely limit
their usefulness.
4. Induction Loop Systems
Induction loops are the most mysterious of the ALDs because they use a varying
magnetic field to transmit the sound from the speaker to your ears. Yet these
are often the cheapest and most versatile systems available.
To use induction loops, you first need to have t-coils in your hearing aids.
Induction loops “connect” to your hearing aids via the t-coils. There is no
physical connection.
There are two “kinds” of induction loops. One is a
neckloop (which you wear
around your neck as the name implies) and plug it into whatever device you are
listening to—whether a personal amplifier such as a
PockeTalker, or an
FM or
infrared receiver, or directly into a radio or MP3 player or iPod. (A variation
of the neckloop are tiny devices that sit on your ears such as
Music Links and
silhouettes rather than hang around your neck.)
The other “kind” of induction loop is a room loop. The typical application for
room loops is for meetings, and for listening to the TV. If you install a room
loop in your house, you can freely move around anywhere inside the loop and
still hear the TV as well as you can sitting right in front of it. I have wired
half my house so I can move around anywhere in the living room, dining area and
kitchen, or go downstairs, and still hear my TV as clearly as if I were right in
front of it. Room loops are relatively inexpensive—under
$200.00.
To learn more about loop systems and how they can help you, read our article,
"Loop Systems—The Best-Kept Secret in Town!"
5. Bluetooth Systems
The new kid on the block are systems that use Bluetooth technology. Think of
Bluetooth as tiny walkie-talkies that allow two devices to automatically “talk”
to each other. The range of Bluetooth is quite limited (a maximum of 30 feet,
but 20 feet is a more reliable figure). With a Bluetooth cell phone and a
Bluetooth device connected to your hearing aids (either directly attached, or
via a Bluetooth neckloop) you can hear and talk on your cell phone even while it
is in your purse or pocket. You can use Bluetooth technology to listen to any
device that has Bluetooth such as some computers, MP3 players, iPods, cell
phones, PDAs (personal digital assistants, etc.)
Phone Systems
While not a separate technology, I’ve made a separate class for telephones
because so many people have problems hearing on them. With phones, you can use
several of the above technologies to help you hear better. For example, you can
use your t-coils to “couple” with your phone’s receiver. You can get
special
amplified phones that give you much more volume if that is your problem, or you
can use a personal amplifier to boost your phone’s volume. Some special phones
have jacks in them so you can plug in a
neckloop or direct audio input (DAI)
patch cord. As well, many cell phones have Bluetooth built in.
Connecting Your Hearing Aids to Assistive Listening Devices
ALDs can work with, or without, hearing aids. For most people the question is,
“How do I make these wonderful Assistive Listening Devices work with my hearing
aids?” Good question. There are four basic methods.
1. T-coils: (Sometimes called telecoils or audiocoils) The most common method of
“connecting” ALDs to your hearing aids is via the t-coils built into your
hearing aids. Then you plug a personal loop such as a neckloop, Music Link or
silhouette into the device you want to listen to. (Note: if you don’t already
have t-coils in your hearing aids, ask your audiologist if they can be
retrofitted. They are that useful!) To learn more about t-coils and how useful
they are, read our article called "Using T-Coils to Couple Your Hearing Aids to Various Audio Devices".
2. Direct Audio Input (DAI): Some hearing aids and cochlear implants have a tiny
jack on the hearing aid itself so you can plug in a “patch cord” and plug the
other end directly into the device to which you want to listen—e. g. a radio,
iPod, MP3 player, computer or various FM receivers and personal amplifiers.
Unfortunately, few hearing aids have DAI jacks.
3. FM receivers: A few hearing aids have special “boots” so you can attach a
tiny FM receiver to them and listen to a person via the corresponding FM
microphone they wear, but these are expensive and limit you to certain brands of
hearing aids.
4. Bluetooth: Similar to the tiny FM receivers (above), but using Bluetooth.
Allows you to listen to Bluetooth enabled devices as mentioned previously.
The latest in hearing aid technology is using a remote control (sometimes called
a “streamer”) that allows the above technologies to easily connect to your
hearing aids. The remote control contains a DAI jack to directly connect to
audio devices and a Bluetooth
receiver to connect with any Bluetooth devices you may want to listen to. You
simply wear the “streamer” around your neck and it wirelessly “talks” to your
hearing aids via its own proprietary technology.
__________________
Assistive Listening Devices have been one of the best kept secrets in town—but
no longer. Now that you know how useful they can be, avail yourself of their
benefits. When used with your hearing aids in difficult listening situations,
the two make an awesome combination!
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