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Living in a silent world -

Before the 17th century, anyone with a hearing problem was pretty much deaf to the world.

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The ear trumpet -

But it was during this time that scientists and educators began to experiment with treatment. One of the earliest devices to appear was the ear trumpet, around 1634.

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The world's first "hearing aid" -

The ear trumpet is regarded as the world's first "hearing aid." They became increasingly common in the late 17th and 18th centuries.

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The first commercial ear trumpets -

The first commercially available line of ear trumpets was established by London-based merchant Frederick C. Rein in 1800. Rein recognized the commercial value in these new contraptions and some of his examples were highly elaborate in their design, for example this swan-shaped silver ear trumpet, with an ivory earpiece.

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Custom-made ear pieces -

F.C. Rein custom made conical ear trumpets as bespoke pieces for a variety of clients. This pair is crafted from gilt brass with ivory earpieces designed to be hidden under the hair.

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Amplifying sound -

By the mid-19th century, a variety of instruments designed to amplify the voice were commercially available. These included hearing horns, conversation tubes, and walking cane trumpets. 

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The hearing horn -

In this 1958 photograph, a couple demonstrate a Chase silver hearing horn, made in 1880 and used by Queen Victoria.

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Alexander Graham Bell (1847–1922) -

The development of the hearing aid was greatly amplified in the 1870s with Alexander Graham Bell's invention of the telephone.

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The use of telephone technology -

Bell's new telephones could control the loudness, frequency, and distortion of sounds. These abilities were harnessed to create the first electric hearing aid.

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Miller Reese Hutchison (1876–1944) -

American electrical engineer Miller Reese Hutchison is credited with inventing the first electrical hearing aid, or Akouphone, around 1895.

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The Akouphone -

The Akouphone used an electric current to amplify weak signals. The signal traveled through a carbon transmitter, so that the hearing aid could be portable.

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The Vactuphone -

In 1926, another American, naval engineer Earl Hanson, expanded the idea of the Akouphone to create the first vacuum tube hearing aid called the Vactuphone. The Vactuphone looked much like a box camera of the day, a deliberate ploy by the manufacturer to disguise its real purpose: the social stigma of being hard of hearing was such that few of those suffering auditory impairment ever admitted to it.

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"Radio ears for the deaf" -

The Vactuphone became an industry leader in the early 1930s. This advertisement reads: "New! Radio Ears for the Deaf."

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Size matters -

New technology not withstanding, the real goal was the miniaturization of the hearing aid, in part so that users could wear a device that was near-hidden from view.

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Clumsy and conspicuous -

For much of the 1930s though, hearing aids remained conspicuous and rather clumsy looking, as demonstrated here where a user is wearing an electrical hearing aid made by British company Multitone Electric Company. The microphone and batteries are carried in the handbag, and the listening device is clipped over the ear.

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The advent of the transistor hearing aid -

Military technological advances made during the Second World War allowed for the miniaturization of the hearing aid. By the late 1940s, models such as the Acousticon hearing aid were based on transistor applications.

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The evolution of the hearing aid -

A transistor allowed the sound output to be altered based on the user's needs. This facility was a major step forward in the evolution of the hearing aid.

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Introduction of electrical hearing aids -

By the mid-1950s, powerful battery driven transistor hearing aids represented the industry standard, and resembled the products we know today. They were far more compact, and finished in a skin tone hue to make them less conspicuous.

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Sound and vision -

Manufacturers around this time even developed a hearing aid designed for deaf moviegoers. A tiny device was placed in the ear as an amplified headset.

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Listening to the soundtrack -

In order to better capture sound waves, the transistor was affixed to an extended cord. At the top of the photograph are the various components that made up the device; below is the hearing aid as the user would have worn it. This appliance served as a precursor to the modern assisted listening devices (ALDs) that most movie theaters today offer clients who are hard of hearing.

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Breakthrough in digital processing -

The next significant advance in hearing aid technology was the breakthrough in digital processing for creating both speech and audio signals pioneered by Bell Labs in the 1960s.

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The introduction of the microprocessor -

Already acknowledged for its work in the field of transistor technology, Bell Labs played a leading role in the development of the microprocessor in the 1970s. In 1982, an experimental prototype of a fully digital hearing aid had been unveiled.

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The hearing aid goes digital -

The age of the digital hearing aid arrived in the 1990s, led by the Danes. In 1996, Widex launched the Senso, the world's first commercially-successful, completely digital hearing aid. Soon afterwards, another Danish hearing aid manufacturer, Oticon, presented the DigiFocus Compact, demonstrated here by the company's then president, Lars Kolind.

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Smaller and more powerful -

In 1999, the Natura was launched. At the time the smallest digital hearing aid in the world, this tiny device was built by Sonic Innovations in the United States. It featured a tiny microchip with nine audio channels, which could be programmed by a handheld computer.

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Invention of cochlear implants -

Taking the digital hearing aid a step further, cochlear implants helped profoundly deaf people to hear. These work by creating simple digital versions of sound and sending them to a receiver implanted inside the wearer's head.

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The hearing aid gets smarter -

Throughout the early 2000s, Oticon and US company Starkey Hearing Technologies further pioneered technological know-how. In 2006, Oticon released a hearing aid with the receiver (speaker) directly in the ear; Starkey, meanwhile, introduced the ELI hearing aid, which enabled Bluetooth connection for the first time.

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ELI hearing aids -

The ELI hearing device signaled a shift towards hearing aids as smart devices. ELI, which plugs into the bottom of most behind-the-ear hearing instruments, offers wireless communication between hearing aid wearers and a growing assortment of modern Bluetooth signal sources.

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Advantages of Bluetooth connectivity -

Most of today's hearing aids are fully connected smart devices, with most premium hearing aids that are Bluetooth enabled allowing for personalized hearing, speech clarity, and reduced background noise. Environmental settings and remote support are also standard.

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The use of earbuds -

Meanwhile, the self-fitting wireless earbud is aimed at helping people who experience mild-to-moderate hearing loss, and are designed for better hearing, music streaming, and phone calls.

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The future? -

We've come an long way since the ear trumpet. But according to the World Health Organization (WHO), by 2050 nearly 2.5 billion people are projected to have some degree of hearing loss, and at least 700 million will require hearing rehabilitation.

Sources: (The Hearing Aid Museum) (World Wide Hearing) (Canadian Audiologist) (The New York Times) (WHO)

See also: Why we should listen to our ears

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