Since the dawn of Man hearing loss has been a true cause for innovation. The first attempt at solving hearing loss was a hand against the ear, which would simply collect more sound waves to make sounds clearer.

This concept remained the same for most of hearing aid history even if the means, style and materials have continuously changed. It is only in the last hundred years that hearing aids have changed dramatically, since electricity has begun to play a part and radically improve what they are capable of.

The ear horn hearing aid

Although there are no recorded dates, it is thought that ear horns have existed in every civilisation for thousands of years since humans first created carved objects. Made from materials like wood, metal and horn, quite simply these early hearing aids were wide at one end to collect sound waves and narrow at the other end to funnel amplified sound into the ear.

The ear trumpet hearing aid

This was a metal version of the ear horn. The only real difference was the improved industry which made them. Ear trumpets could be produced in a range of styles, shapes and sizes to suit the preferences of the customer, and the varied extent of their hearing loss. These hearing aids were being used by many people from the 1700s onwards, including Beethoven.

The Nineteenth Century and concealed hearing aids

With increasing concern over how hearing aids were being perceived in public, the 1800s saw a large increase in the amount of hearing aids which could be concealed, hidden or simply made less obvious, and more decorative  as well as functional.

This may have helped people with a hearing loss to wear hearing aids in public, since they were often crafted artistically to look more socially acceptable and fashionable. Some were even covered in flesh-tone enamel for added concealment, or matched to the hair colour of the wearer.

The acoustic throne and acoustic chair hearing aids

For the royalty of Europe however, walking around in their finest robes and dresses with an ear horn or trumpet against their ears seemed to be getting more laughs from their loyal subjects than loving admiration. It simply wasn’t kingly or queenly to have a servant stood only two feet away shouting down a horn in to the royal ear. The ear horn was for commoners, and some monarchs with hearing loss preferred to receive visitors while seated on specially-made hearing aid thrones.

These adapted seats included built-in tubes which would collect the sound of a voice several feet away and channel it up in to an echo chamber inside the throne, which would amplify the sound coming out of the seat around the monarch’s head. The throne was even mobile, so that wherever the monarch went they could hear the voices of subjects without them having to get too close.

On a more practical level, it was widely believed that ‘bad air’ and bad breath spread disease, so that having people speaking right in to your ear all the time made you more likely to get ill. Of course, being shouted at by many different people could make you more likely to catch a cold, even if we know nowadays that halitosis is an unlikely carrier of a deadly disease.

Auricles

Among the first types of concealed hearing aid, auricles were composed of a small metal sound collector shaped like a trumpet, shell or flower attached to a thin metal headband. They were hands-free and could be concealed to an extent in the hairline.  Or in the case of flower-shaped auricles, made to look like decoration rather than a hearing aid.

Acoustic Fan hearing aids

Popular with women in the nineteenth century, these thin metal fans collected sound when held behind the ear, and funnelled it in to an attached hearing aid earpiece or small ear trumpet. These instruments could help hearing to a certain extent, but their main benefit was discreetly telling people you had a hearing loss, so that they would know to speak more loudly. There were also fans which used the process of bone conduction.

Bone conduction hearing aids

The effect of bone conduction happens when sound waves are collected in a device and transferred to the ear as vibrations in the bones or teeth. Although it was written about in the 1500s, it wasn’t used to help hearing loss until the 1600s. By the Victorian era it was used in hearing aids like audiphones.

The Audiphone hearing aid

This bone conduction hearing aid fan was patented in 1879. The user would grip the end of the fan between their teeth, so that sound vibrations collected by the thin body of the fan would be transmitted through the teeth and skull, and in to the inner ear.

They may seem like a strange idea, but some bone conduction devices like the audiphones could improve hearing by as much as thirty decibels and the method is still used today with items like bone-conduction phone receivers. Then as now however, the vast majority of hearing aid devices remained air-conduction instruments, collecting sound vibrations from the air.

The Beard Receptacle hearing aid

This hearing aid was designed to be concealed within the large beard of the wearer. The curved body of the hearing aid collected sound, and funnelled it up in to a pair of earpieces. It was recommended that the user should wear a scarf to help keep the hearing aid secure, and to conceal it further.

The Hair Receptor hearing aid

The hair receptor hearing aid was shaped like a wide headset, covered with silk and flat enough to be concealed beneath a woman’s bouffant hairstyle.

This hearing aid is prime example of the growing desire in the Victorian era to hide hearing aids as cleverly and effectively as possible to avoid them being seen.

Acoustic Table Urn & Vase Receptacle hearing aids

Made from the early 1800s onwards, these table-top hearing aids were designed to collect multiple sounds from different directions and funnel them in to a hearing tube. These hearing aids were designed for use during conversation around the table, but were also designed to hold flowers or fruit in order to be concealed, and to appear more as table decoration.

Acoustic Cane, Umbrella and Parasol hearing aids

These hearing aids were disguised in handles, where sound was collected in the tip of the hollow handle and funnelled in to an ear piece coming from the handle base. The handle would be rested upon the shoulder so that the earpiece could swivel out to be fitted in the ear during conversation.

Opera Glasses & Lorgnettes hearing aids

These devices combined hearing aid with optical aid, ideally for use in the opera house when seeing and hearing a distant performer was a struggle, especially for those with a hearing loss. Some ‘opera glass lorgnettes’ were even designed with the hearing trumpet section disguised as the handle of the eyepiece.

Opera Dome hearing aids

Known as Opera Domes because of their popularity with patrons of the theatre, these cup-shaped hearing aid trumpets were used in exactly the same way, but came in a wide range of shapes, styles and sizes to suit the tastes and hearing loss of the individual user.

Mourning Trumpet hearing aids

Attitudes in the Victorian era placed a lot of emphasis on mourning the death of a loved one, and even Opera Dome hearing aids came suitably disguised in black fabric, lace and ribbon to match the black mourning clothes of the owner.

Tapered cone hearing aids

Designed especially for ladies’ use, these slender and more feminine versions of the ear trumpet hearing aid were covered in silk, lace and ribbon for concealment, and were often attached to a dress or tied around the neck with a silk cord.

Artificial Concha hearing aids

This more compact and ornate design of hearing aid was one of the first to be moulded to the ear of the user, and specially designed to complement the wearer’s jewellery and hairstyle. With the decorative appearance of an ornate shell, it acted to collect and funnel sound in to the inner ear. It was self-retaining, so that nothing was needed to hold it in place, and its smaller size was normally well suited to people with mild hearing loss.

Bouquet Holder hearing aids

A hearing aid composed of a palm-sized metal dome and rubber hearing tube. The dome could be worn on a dress and concealed by fabric, while also holding several flowers to act as an ‘acoustic ornament’.

Acoustic Hat hearing aids

For men who preferred not to carry a small bouquet around on their front, the acoustic hat was a clever way of hiding an ear trumpet hearing aid. The sound was collected in the main body of the hat above the head, while a discreet listening tube would be the only thing seen on the outside.

The Magneto-Telephone hearing aid

This type of hearing aid was designed to use a transmitter disguised as a badge to be worn on the jacket or in the breast pocket. Although in 1892 it was the earliest electric hearing aid to be patented, this type was never actually made.

The final years of the nineteenth century gave birth to the idea of electrically-powered hearing aid instruments, and in 1899 the first electrically-powered hearing aids could be bought for about $400. Most people could never afford one on an average wage of a few dollars per week, but it would only be a matter of time before the technology would become much more effective, and much more affordable. The basic components were there; a battery box, earpiece and microphone, which at the time was made of carbon dust but would later be refined.

The Twentieth Century and Electrical hearing aids

1900 - 1930: Carbon Microphone, Acoustic tube and Stethoclare hearing aids

The earliest electric hearing aids ran on carbon batteries and looked slightly like the first telephones. Worn around the neck, they were large and cumbersome with many wires and with a large, heavy battery with a very short life of a few hours.

During the early decades of the 1900’s, with electric hearing aids being unreliable, costing too much for widespread use and with batteries only lasting for a few hours, many people still used improved versions of older non-electric types. The flexible acoustic tube had been used by many since the late 1800s and was still in use, being a simple rubber tube with a mouthpiece for the speaker, and an earpiece for the listener. It was simply a much shorter version of the tubes used to communicate on warships.

The Stethoclare, a table-top sound collector and listening tube, was a much smaller version of the vase receptacle or table urn, and its improved design meant that it could pick up more sound than its ancestors while only measuring eleven centimetres across.

1930’s: The Bone Conductor hearing aid

Invented in 1933, this hearing aid transmitted sounds in to vibrations which could be felt against the side of the head. The bone of the skull transferred the vibration as sound, meaning that if the ear no longer functioned the wearer might still be able to pick up sound. However, the bone conductor was known to cause headaches as a result of the way it worked.

1948: The transistor

The invention of the transistor replaced valves in radios, and made electrical components and devices smaller and more reliable in every technology. The transistor could also make electric hearing aids lighter, much smaller, and less likely to break down.

The transistor was first used in the hearing aid in 1952, the first product to do so. The transistor radio, widely hailed as the spark for rock n’ roll youth culture, was not available until 1954.

1950’s & 1960’s: Magnetic microphones, shrinking transistors and Behind-The-Ear hearing aids

Smaller transistors allowed circuits to be much smaller and produced much more cheaply. They worked more effectively and used less power, so that by the end of the 1950’s transistors had changed the face of technology, and hearing aids were no exception.

One of the first hearing aids to use a transistor was the Oticon T3 made in 1953. It was compact and portable enough to fit in the wearer’s pocket.

New microphones which worked magnetically performed much more effectively than older carbon types, and hearing aids had become small enough to fit in a pocket or under clothes. The wearer could be less conscious about using a hearing aid, since it was now easier to conceal the instrument.

By the mid-fifties all-in-one hearing aid units could be worn behind or over the ear. The above model is a Zenith Diplomat from 1956.  Hearing aids now included a transistor circuit, battery and microphone all in one unit. They were improved still further when in 1969 directional microphones were being used to give the wearer a more natural hearing experience.

1970’s: Integrated circuits and ITC units

Integrated circuitry was now being built in to all-in-one hearing aid units, which could help the wearer to differentiate between background noise and the sound of speech they wanted to hear. Batteries were now so small that the first In-The-Canal hearing aids were being produced, offering increased discreet hearing aid design.

1980’s: Lithium Batteries & Digital Sound Processing in Hearing Aids

Lithium batteries provided longer lives for hearing aid circuits, and dropping prices made the hearing aid more of an affordable, attainable solution to the problem of hearing loss.  In 1984 came the very first digital hearing aids, using Digital Sound Processing to pick up speech more clearly, as well as offering more potential for features like volume control and feedback reduction, which were already in development.

1990’s: Full digital processing, volume control and Adaptive Speech Alignment

The result of the advances made in digital sound processing in the eighties meant that by the nineties, hearing aids could be programmed and fine-tuned to different noise environments. Analogue technology gave way to digital, which rapidly increased the level of finesse that hearing aids could be programmed with. Hearing aid performances could now be adjusted by the user to suit their personal needs and preferences.

Following earlier advances volume control was now automatic or adjustable by remote. The circuitry had become small and sophisticated enough to allow hearing aids to be worn inside the ear canal, being all but invisible to passers-by. Adaptive Speech Alignment, a result of audio processors now working completely in digital formats, meant that the sound of speech could be automatically picked up over background noise, and sound signals dually processed for vowels and consonants. In 1996 Behind-The-Ear and In-The-Ear hearing aids were now available as completely digital instruments, which could compute forty million instructions per second.

2000 - 2010: Feedback elimination, memory settings and listening preference

With hearing aid hardware capable of being tucked away almost invisibly in to the ear canal , attention was turned to perfecting the software which was available to create a digitally-enhanced hearing experience. Improved software reduced feedback which had plagued older models. Preferred settings and removable memory devices meant that a hearing aid could perform specifically to the user’s tastes and needs without having to be manually readjusted.

2010: Patient Input, Fuzzy Logic and ADRO

Modern hearing aids are fitted with the patient’s specific tastes and hearing needs as the basis for hearing loss treatment. Improved hearing check techniques and customisation processes can create hearing aids specifically moulded to fit the shape of an individual ear for complete comfort. Hearing testing can be carried out that will narrow down the range of sounds the patient struggles to hear, and to make changes to the hearing aid software that will pick up the sounds they most want to hear.

Fuzzy logic refers to the digital software used in modern hearing aids that decides which settings to use at any one time. This modern software is capable of dealing with unclear or ‘fuzzy’ decisions, rather than simply yes/no decisions, so that a range of presets such as volume level, background noise cut-out, feedback elimination and directional sound pickup can be juggled and changed constantly.  The result is a hearing experience that is closer than ever to matching natural hearing as a fluid, seamless experience.

Adaptive Dynamic Range Optimisation, or ADRO, is the type of software that allows this fuzzy logic to work. It means that the modern digital hearing aid adjusts itself from second to second in order to pick up sound signals which will be most desired and most useful to the wearer at any one time.

The next 30 years..?