"Say no to plagiarism. Get a tailor-made essay on "Why violent video games should not be banned"? Get an original essay Hearing aids are very interesting technological tools. The first one seemed a kind of musical instrument placed inside the ear. Today it is a small plastic device that can go unnoticed by those around you and be much more effective. But how did it go from a large metal horn to a small piece of plastic? It all started with the telephone developed by Alexander Graham Bell in 1876. In 1876, several hearing-impaired people found it easier to hear through Bell's telephone since the receiver was close to the ear, however, Thomas Edison thought of a he had a better idea and in 1878 he developed a carbon transmitter for the telephone that amplified the input signal. Although Edison was on the right track with the amplification of the electrical signal, the voice was only amplified by about 15 decibels and the telephone was. still big and heavy, hardly. something practical. To get a better perspective on decibels in terms of speech, a person raises their voice 30 decibels to allow those with impaired hearing to hear. By 1907, Lee De Forest's vacuum tube hearing aids produced 70-decibel amplification which far exceeded the 15-decibel amplification created by Edison. Although this model surpassed that of its predecessor, it weighed a good 100 kg and was still very large – hardly transportable for everyday use. The main purpose of this model was to demonstrate that speech could be amplified without a person raising their voice. However, in 1924, this 100 kg was reduced to 4 kg and allowed the device to be placed in a small wooden box. Thanks to this advancement in vacuum tubes, the hearing aid was finally portable; However, not many people wanted to carry it with them because they didn't want others to know about their hearing problem. The first wearable hearing aid was developed by Aurex Corp. in 1938 and consisted of a small earpiece and a cord connected to a clip-on amplifier. /receiver. This project was only made possible by Norma Krim's development of subminiature vacuum tubes which required less energy in addition to their smaller size. This product became much more popular on the market as it was more hidden from people's sight while in use; however, they still had to use a strap battery pack. In 1948, Bell Telephone Laboratories invented the transistor which enabled the production of transistorized hearing aids. This invention paved the way for more compact models where batteries, amplifier and microphone were combined into one small unit. The only problem with these models was that they were still difficult to hide when in use. It wasn't until the late 1950s that hearing aids could be worn completely on the ear. The Otarion Listener developed by Otarion Electronics in the late 1950s was the first hearing aid that could be worn completely on the ear while retaining the electronic components in the glasses. The idea of ​​a hearing aid with glasses began to spread because it was much more convenient to wear and easier to hide. Even people with perfect vision wore these hearing aids with glasses due to their concealment. Zenith Radio then developed a behind-the-ear model in 1964 that weighed just 7 grams. This device consists of an integrated circuit amplifier, a 1.2V button battery and a microphone. Basically, everything except the microphone is inserted into one unit and clipped in"