Hearing aids in the strictest form of the term have been around forever. When early man shouted a greeting or a threat from a distance, the listener in all probability cupped his hands behind his ears in order to better hear what was being shouted to him. In general, people did not live a long time before several hundred years ago, especially the poor and the very rich, so deafness was not the problem that it is today.
People were either born deaf or went deaf through illness. People did not become deaf through being old or through industrial noise because there were no machines. The poor died of hard work and sickness and the rich were assassinated. Scholars and monks were probably the only classes that lived into old age and scholars were often monks and visa-versa. These people were certainly clever enough to have developed the hearing trumpet from the cupped hand.
But that is all that mankind had for thousands and thousands of years. More of the sound (or vibrating air) was caught by the cupped hand or trumpet (thereby enlarging the outer ear) and forced into the inner ear. Then, all of a sudden in historical terminology, along came electricity and wiring and circuitry and batteries not much more than a hundred years ago.
Modern hearing aids work on much the same principle. A microphone collects the sound, amplifies it and instantaneously plays it back through a loudspeaker which is placed in or behind the ear. Owing to the level of technology, the early hearing aids were big and unsightly. The battery was the size of a house brick and so was the amplifier. The microphone was large and the speakers were headphones. There was a little volume control, but on the whole, you got what it gave you.
These days hearing devices still work on the same principal, but micro technology has allowed manufacturers to miniaturize the set-up so that all the components fit in one small unit, which is then put in or behind the ear. Most of these hearing aids can be adjusted in some way to suit the wearer's personal hearing difficulty. This is because not everyone is impaired to the same degree and not everybody has problems with the same frequencies.
Furthermore, the environment you are in can make a lot of difference to the effectiveness of the deaf aid and therefore, modern units permit the wearer to filter out some surrounding noises like wind rush or heavy machinery. There is also much more volume control than before. Volume control can even be set on automatic.
The basic form of hearing aid is the analogue system, the same kind as was first invented for batteries but much, much smaller. These are normally BTE (behind the ear) units. The next type is the programmable analogue hearing aid. This device is programmable for use in different predicaments and is a great advance on the simple analogue process.
The last category is the modern digital hearing aid. It is also the most effective and the most expensive. Its circuitry is capable of Digital Sound Processing or DSP. These digital aids use many millions of sound codes to identify frequencies and then either filter them out or amplify them. The difference is like going from vinyl records to CD's.
More Information:
Owen Jones, the author of this article writes on quite a few subjects, but is at present involved with
hearing aids comparisons. If you would like to know more or check out some great offers, please go to our website at
Digital Hearing Aids Prices.
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