From Concept To Production
Micro Electronic Scientist Class D Hearing Aid Circuit Board
Building Prototype Magnified 100's of times
Cutaway of a Open Fit Behind the Ear Advanced Digital Hearing Aid
Timeline of a hearing aid: from
concept to completion
Hearing aids have come a long way from the ear trumpets and
large, box-shaped instruments previous generations used to amplify sound in
their environment. Today, hearing devices are small enough to fit almost
invisibly inside the ear canal while still containing technology so advanced it
can distinguish speech from background noise and work compatibly with other
technology you use on a daily basis.
How long does it take to make hearing aid? From concept to
the process can take more than ten years and involve as many as 500
engineers, consumers, hearing healthcare professionals and retailers – all of
whom are focused on creating usable instruments which will enhance quality of
life for those who wear them.
Research and development
Developing a new, high-end product can involve 200-300
people over a period of three to four years, especially when the manufacturer
is introducing a new platform and design but all hearing devices begin as an
Many of them come from people just like you – individuals
with hearing loss who want to hear well in every listening situation. You tell
your hearing healthcare professional what your hearing challenges are and they
relay that information back to the hearing aid companies.
Ideas for new hearing aid designs also come from hearing
health professionals and retailers, as well as from the latest technology. Once
hearing aid companies understand what challenges users are facing, they begin
the process of manufacturing a solution.
“Technology is changing all the time. So is the concept of
aging,” Mandy Mroz, Digital Director for Healthy Hearing said. “Today’s 65
year-olds don’t consider themselves old. Consumers are very engaged in health
and hearing health and have high expectations. That’s a new type of patient for
the hearing health professional.”
For example, cell phone technology prompted companies to
develop devices which can be controlled with smart phone applications. The goal
was to develop user-friendly devices which are easy for the young – and the
young at heart – to use on a daily basis.
If the technology doesn’t exist, development is the most
time consuming part of the process. For example, one of the biggest complaints
current hearing aid users have is the ability to distinguish voices from other
background noise. In 2013, researchers at Ohio State University found a way to
break sound into units of either speech or noise, then discard the noise. Dr.
Eric Healy, a professor of Speech and Hearing Science at OSU who worked on the
new technology, said he hopes the technology will be on the market within the
next 10 years.
Prototypes with new technology must undergo clinical testing
in order to gauge its effectiveness. Companies give their data to the Food and
Drug Administration (FDA) in order to secure permission to market it to
consumers. That’s because hearing aids are classified as medical devices and
must meet strict guidelines.
For example, the FDA recently allowed marketing of a new
hearing aid that uses a laser diode and direct vibration of the eardrum to
amplify sound. The EarLens Contact Hearing Device (CHD), manufactured by
EarLens Corporation of Menlo Park, California, is designed for use by adults
with mild to severe sensorineural hearing impairment. The CHD uses the user’s
own eardrum as a speaker and enables amplification over a wider range of frequencies.
Another example of new technology currently in the testing
phase comes from researchers at the University of Stirling in Scotland who are
currently working on a hearing device that will contain a miniaturized camera
that can lip-read, process the visual information in real time, and help the
user seamlessly switch between audio and visual cues. The researchers expect
the new software will enhance communication for users in difficult listening
environments, such as noisy restaurants or public transportation venues like
airports and train stations.
The concept is one that Gerald Kidd, a professor of speech,
language and hearing sciences and specialist in psychoacoustics at Sargent
College at Boston University, has been working on since 2011.
A prototype of Kidd’s VGHA device has been in the testing
phase since late 2014. He’s hoping hearing aid manufacturers will become
interested enough in the device’s potential to make it wearable.
Design and manufacturing
Once the technology has been tested and approved by the FDA,
engineers must collaborate on design and manufacturing. Although the components
themselves may not be expensive, making them fit into attractive, wearable
devices can be tricky. Today’s consumer prefers inconspicuous devices which work
unobtrusively in the background and won’t interfere with their active
Some manufactures have their own production facilities
because the devices require such specific skills and equipment to make that
it’s difficult to outsource them. Large production facilities can produce as
many as several thousand instruments every week.
It’s no secret that hearing aid technology has changed
dramatically in the last 50 years. Not long ago, hearing healthcare
professionals used screw drivers to manually adjust their patient’s hearing
devices. Today, digital hearing aids are accurately programmed from a computer
and customized to each patient’s specific hearing loss and lifestyle.
That’s exciting for consumers with hearing loss, but it
means hearing healthcare professionals must be constantly learning about new
devices are on the market to understand how to fit them for the best possible
Finally, the device is ready to offer to the general public.
Many of the big companies, such as Seimens, Starkey, Rexton, Hansation, Audina and Phonak; only supply
their products to hearing healthcare professionals who directly fit and sell to
patients they see in person. That’s because research indicates individuals will
have more success wearing their hearing aids if hearing loss has been correctly
diagnosed, patients have been carefully counseled and the hearing aid has been
properly fit and adjusted.
What does all of this mean? Although making a hearing device
is a time-consuming process, the consumer can be assured the hearing devices
they receive from qualified, licensed hearing healthcare professionals have
been thoroughly researched, manufactured, tested and FDA approved. Although the
process may take as many as ten years, the successful result it provides for
those with hearing loss is worth the wait.