A little bit of history and an explanation of how analog devices work versus how digital devices work is essential to understand the differences between digital and analog hearing aids. Analog technology appeared first, and as a result most hearing aids were analog until digital signal processing (DSP) was invented, after which digital hearing aids appeared. The majority of (roughly 90%) hearing aids purchased in the US at this point are digital, although you can still find analog hearing aids because some people have a preference for them, and they’re often cheaper.
Analog hearing aids handle incoming sounds by taking the electrical sound waves as they emerge from a microphone and amplifying them “as is” before sending them to the speakers in your ears. On the other hand, digital hearing aids take the same sound waves from the microphone, however before amplifying them they turn the sound waves into the binary code of “bits and bytes” that all digital devices understand. After the sound has been digitized, the microchip within the hearing aid can process and manipulate the information in complex ways before transforming it back to analog sound and delivering it to the ears.
It is important to remember that analog and digital hearing aids serve the same purpose – they take sounds and amplify them so that you can hear them more easily. Both types of hearing aids can be programmed by the dispensers of the hearing aids to produce the sound quality desired by the user, and to develop settings ideal for different environments. As an example, there can be distinct settings for low-noise rooms like libraries, for busy restaurants, and for large areas like stadiums.
Digital hearing aids, because of their ability to manipulate the sounds in digital form, generally have more features and flexibility, and are often user-configurable. They have an array of memories in which to save more environment-specific settings than analog hearing aids. They can also employ sophisticated rules to identify and reduce background noise, to remove feedback and whistling, or to selectively detect the sound of human voices and “follow” them using directional microphones.
In terms of price, analog hearing aids are in most cases cheaper, although some digital hearing aids are approaching the cost of analog devices by eliminating the more advanced features. There is commonly a noticable 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 .