Hearing aids essentially fill the gap created by a hearing loss. This is done by receiving and amplifying sound. There are two types of hearing aid technology that serve as the basis for receiving and amplifying sound within a hearing aid: Analog Technology and Digital Technology.
Hearing aid technology can be divided into two general categories: analog hearing aids and digital hearing aids. In very simple terms, analog and digital refer to how the hearing instrument's amplifier processes sound. Both of these categories can be further divided into more specific subcategories:
Analog hearing aids amplify the continuous sound wave by simply making it larger. There are two subcategories of analog hearing instruments: conventional hearing aids and programmable hearing aids. Conventional and programmable hearing instruments differ in the amount and degree of adjustments the hearing aid dispenser can perform on the hearing device. A programmable hearing device allows the dispenser to adjust the amplifier more precisely to match your hearing loss. Programmable analog hearing devices, when compared to their conventional equivalent, provide greater fitting flexibility. This means that the dispenser can more readily change the way a programmable analog hearing device operates through the use of an office computer. Sometimes the added flexibility of a programmable hearing aid is an important feature.
Digital hearing aids take the continuous sound wave and break it up into very small, discrete bits of information. This is called digitizing the signal and all digital hearing aids do this. The very fact that a hearing device is digital does not make it better than a comparable analog hearing aid device. Beyond just digitizing the sound prior to amplification, there are differences in exactly how various digital hearing aid devices amplify or process sound. The more sophisticated digital hearing aids are able to amplify the softest sounds of speech while at the same time subtracting out certain types of unwanted noises. Digital signal processing allows hearing aid designers to write computer programs, called algorithms that can be customized to each individual's hearing loss. In addition, digital hearing aids enable important features -- such as dual microphones and low battery warning signals -- to be placed into a small in-the-ear device. It is this potential that makes digital hearing devices so promising for so many hearing losses. Selecting the type of hearing aid that is right for your hearing loss and unique listening needs requires the guidance of a professional well versed in all of variations of hearing instrument technology. Today, over 75% of all hearing aids sold are digital.