|Digital Televisions and Hearing Loss
| by Steve Hillson
Equipment Specialist, HSDC Seattle
February 18, 2008
When traditional, analog television signals came to an end on June 12th
of 2009, there were three choices for
dealing with the new digital television environment.
- Keeping your old analog TV and connecting your antenna to a
digital-to-analog converter box.
- Purchasing a high-definition, digital television to take full
advantage of the new broadcast and cable technology.
- Subscribing to a cable television service that provides an
analog signal to your existing analog TV.
On the surface, this appears to be simple enough.
It is important to note that digital television reception is very
different from analog reception.
When an analog TV gets poor reception, it is often possible to watch the
snowy picture, listen to the scratchy audio and follow the program
anyways. The digital TV screen, on the other hand, is either 100% on or
100% off. When the digital signal is interrupted the entire picture may
freeze or drop out, and all sound will disappear. Following a program
can become very difficult when chunks of the image and whole parts of
the dialogue go missing. Constantly getting up to readjust the TV
antenna could become an annoying fact of life if you live in an
apartment building or busy urban environment. In addition, hills and
large bodies of water can create digital dead zones where no signal is
available at all.
For best results, the FCC recommends an external TV antenna mounted on a
35 foot tall pole. Since that is not an option for many people, an
amplified HD indoor antenna should provide better reception than
standard "rabbit ear" sets can. Visit www.antennaweb.org for more information about
indoor and outdoor antenna options for digital TV reception.
Digital cable, on the other hand, will provide an uninterrupted signal
to your digital TV or your digital-to-analog converter box. Whether or
not cable services are worth the monthly charges for the way you watch
TV, I can't say. If you are considering signing up for cable, make a
list of your regular TV viewing habits and see which service packages
best match your needs.
For those of you considering a new, digital television, I've done some informal research at local electronic stores. Most of the salespeople I spoke with hadn't considered the effects of hearing loss, but were willing to think it through when I explained what features would be useful for hard of hearing and Deaf people. Just like buying a car, if you don't understand the basic technology, you could get taken for a ride.
I've also noticed that most stores have their display models optimized
to provide an eye-popping visual experience. This can be amusing the
first time, but unless the characters in your favorite program always
wear lime green jackets with shocking orange hair, you are going to want
to look past the bright colors and pay attention to what any specific
television can do for you. I'm going to break this down into a kind of
check list that I hope you will find useful.
Unlike the often disappointing speakers found in many older TVs, the new digital units often have very good speakers built into them with internal menus that allow you to adjust the high (treble) and low (bass) frequencies for better clarity. There are even some digital TVs that offer a "voice enhancement" feature which automatically turns down the background noise and turns up the frequencies in the speech range. You can reproduce this effect by reducing the bass levels and turning up the treble until the voices sound clearer.
At the heart of things, hearing aids and CI processors are designed to focus on one person speaking in front of you in a quiet room. Think of your TV as that one person. Ask the sales person to walk you through the audio menu, and if possible, listen to the same program with the factory preset levels and then adjust the audio settings to try to improve the speech clarity.
Assistive Listening Systems
People who prefer to use Assistive Listening Systems still have that option. This is a good solution if the TV will be shared by others who don't have a hearing loss because the listening system operates independently of the TVís own volume level. All assistive listening equipment is designed to connect to the analog Audio Output jacks. Some recent TVs only offer digital (Coaxial or optical TOSLINK) Audio Output connections. Digital-to-Analog audio converters are available for both types of digital output.
Analog Audio Outputs
Digital Audio Outputs
Some TVs come with these Audio Output jacks disabled. You may need to go into the TV's audio menu to activate these output connections. Tell the sales person that you want to connect an analog listening device to the TV. They can walk you through the menu and demonstrate how to activate these outputs and show you a digital-to-analog converter if that is going to be necessary.
Recently, some TVs have been made that automatically turn off the TV speakers whenever the Audio Output jacks are being used. There are also some models that have Audio Output jacks that are not connected to anything inside the TV. These are simplified TVs that use recycled parts from previous models. In any case, itís always a good idea to talk with the sales staff about how you want to use the Audio Output jacks before making a purchase.
Also, watch out for TVs that are actually video monitors. These TVs only have a single, HDMI cable connection available. This is strictly an input jack. There is no way to connect an assistive listening system to a video monitor. The audio output jacks on a cable box, DVD player or sound system amplifier can be used instead.
Plasma TVs are based on chemical reactions in the screen that produce
infrared light as a by-product. Infrared listening devices can pick up
this background light as an annoying static or buzzing sound. If plasma
is the technology of your dreams, you should consider using a radio
frequency listening device such as the
Direct Ear series .
These radio frequency systems connect to the TV just like their infrared
counterparts, but without the sensitivity to the infrared light produced
by the plasma screen. They also offer the benefit of allowing you to
walk around the home or to go outside to the porch or garden while
listening to your television program.
Home Theatre Systems
Besides stunning visual content, digital TVs promise a wide range of
audio options from simple stereo to surround sound with any number of
extra speakers. There is more to it than buying a TV and a box of 4
speakers. Serious audio/video stores offer a range of sound systems for
that "theatre" experience in your home. When you see systems described
5.1 or even 7.1, this indicates the number of speakers involved with the
.1 referring to the sub speaker that provides that rumbling bass sound
you can feel as much as hear.
These speaker systems can be alot of fun to play around with, but
bringing a hearing aid or CI processor into the mix raises questions
that are not addressed directly by the manufacturers. Think of the last
frustrating time you had at a movie theatre and then imagine paying your
hard earned money to reproduce the effect in your own home on a daily
basis. Your hearing aid or CI processor should be considered part of the
sound system you are buying.
Standard hearing programs tend to make the hearing aids or CI processors
act like little directional microphones that filter out environmental
noises and emphasize the speech sounds in front of you. Without careful
adjustments, home theatre systems can scatter speech and other important
environmental sounds. For instance, when an actor starts speaking from
the left side of the screen and then walks across to finish speaking on
the right side of the screen, the chances are that it will seem like two
different people are talking.
If there is a home theatre in your future, talk to your audiologist
about creating a "TV" program for your hearing aid that would be
omni-directional with a low compression factor to reduce any distortion
of the music and sound effects from the home theatre speakers.
You will want to find a salesperson you can trust to help you build a
home theatre. It will take a fair amount of experimentation to design a
system that successfully accommodates your hearing loss.
Like any televisions sold in the US, digital TVs must have closed caption decoding ability. You will want to have the sales people go into the TV's control menu and preview the captioning options for you. I have noticed a wide range of captioning styles used by the various manufacturers. Some are large and clear, others are fuzzy and some are too small for comfort. Most digital TV's offer some control over the caption display, allowing you to adjust size, letter shape and the background color of the captions. If you are a routine caption reader, you really want to test drive these features before making any purchase.
Many digital converter boxes also come with built in closed caption
decoders. These often allow you to adjust the size and color of the
captions. Check the product description on the box or the user manual
for more details.
There are a few technical problems related to the use of closed
captioning that you will want to investigate before making a purchase:
Plasma TVs have a problem with their screens called "burn in" that you
need to be aware of. Burn-in happens when there is an image shown
repeatedly in the same place on the screen for long periods of time.
This can cause a permanent "ghost" image to remain on the screen no
matter what you are watching. For example, watching mostly widescreen,
letterboxed movies can cause the "black bars" to burn into the screen
after many hours of use.
Closed captions can also burn into the plasma TV leaving one or more
gray stripes on the screen even when the captions are turned off. If you
rely on captions, you will want to discuss this burn in problem with
your salesperson who should be able to suggest non-plasma TVs for you to
If you already have an older plasma TV, check to see if the caption menu
allows you to move the position of the captions from the bottom to the
top of the screen. Changing the caption location on a frequent basis
should protect your existing plasma screen from burn-in damage.
Another technique is to turn off the captions when your show is over and
let the TV run for about 20 minutes or so to exercise that part of the
screen. This should help to prevent the worst of the burn-in effect
HDMI and CC signals
HDMI is a common technology for connecting home theatre equipment such
as DVD players to a digital TV. Unfortunately, the HDMI connection
strips out the closed caption signal from incoming DVDs and cable
programming. As a result, the TV's built-in caption decoder becomes
It is possible to reroute the DVD player and cable box into the TV using
the component (Audio/Video) connectors (these are the round,
multi-colored plugs on the side or back of the TV). However, the quality
of component video is lower than HDMI, so this may not be a long-term
The current advice for enjoying the benefits of HDMI technology is to
purchase a DVD player and request a cable box that has its own closed
caption decoding ability. These merge the captions into the video signal
where the HDMI technology doesn't interfere with them.
Internet and On Demand cable services
Another issue related to closed captioning is not so much a television
issue as it is an internet regulation problem. Digital cable companies
are able to offer additional features such as On Demand programming by
merging high-speed internet into their standard cable signal.
When you order your favorite film these days, it is usually not coming
from your local cable company directly. Instead, the program is being
sent over the internet and channeled into your cable connection.
Standards for internet captioning are not set yet, and what you are
watching may be an internet entity, not a pre-recorded tape or DVD which
is covered by existing captioning legislation. Talk with your cable
company about closed caption availability in the various parts of their
service packages to avoid paying for extra features that you can't
Please contact us with any questions you may
have at 1 (888) 328 2974, or store(at)hsdc.org