A little bit of history and an explanation of how analog devices work versus how digital devices work is necessary to understand the distinctions between analog and digital hearing aids. Historically, analog technology appeared first, and as a result most hearing aids were analog until digital signal processing (DSP) was invented, at which point digital hearing aids appeared. At the moment, the majority (90%) of the hearing aids purchased in the US are digital, although analog hearing aids are still offered because they are often less expensive, and because some people prefer them.
Analog hearing aids handle inbound sounds by taking the electrical sound waves as they leave a microphone and amplifying them “as is” prior to sending them to the speakers in your ears. In contrast, digital hearing aids utilize the same sound waves from the microphone, however before amplifying them they turn them into the binary code of ones and zeros that all digital devices understand. This digital data can then be manipulated in numerous complex ways by the microchip inside the hearing aid, before being converted back into ordinary analog signals and delivered to the speakers.
Remember that both analog and digital hearing aids serve the same purpose – they take sounds and boost them so that you can hear them more easily. Both analog and digital hearing aids can be programmable, meaning that they contain microchips that can be customized to alter sound quality to suit the individual user, and to develop different configurations for different environments. For example, there might be different settings for low-noise rooms like libraries, for noisy restaurants, and for large areas like stadiums.
Digital hearing aids, because of their ability to manipulate the sounds in digital form, often have more features and flexibility, and are commonly user-configurable. For example, digital hearing aids may offer numerous channels and memories, permitting them to save more environment-specific profiles. They can also use sophisticated rules to detect and reduce background noise, to eliminate feedback and whistling, or to selectively detect the sound of voices and “follow” them using directional microphones.
Cost-wise, most analog hearing aids continue to be less expensive than digital hearing aids, however, some reduced-feature digital hearing aids are now in a similar general price range. There is commonly a perceivable difference in sound quality, but the question of whether analog or digital is “better” is entirely up to the wearer, and the ways that they are used .
