A bit of background and an explanation of how analog devices work versus how digital devices work is essential to understand the differences between analog and digital hearing aids. Analog technology appeared first, and consequently most hearing aids were analog until digital signal processing (DSP) was invented, at which point digital hearing aids appeared. Currently, the majority (90%) of the hearing aids purchased in the United States are digital, although analog hearing aids continue to be offered because they’re often less expensive, and because some people prefer them.
The way that analog hearing aids work is that they take sound waves from the microphone in the form of electricity and then amplify them, delivering louder versions of the sound waves to the speakers in your ears “as is.” In contrast, digital hearing aids utilize the very same sound waves from the microphone, but before amplifying them they turn the sound waves into the binary code of ones and zeros that all digital devices and computers use. After the sound is digitized, the micro-chip within the hearing aid can manipulate the information in sophisticated ways before converting it back into analog sound and delivering it to your ears.
Analog and digital hearing aids perform the same function – they take sounds and amplify them to allow you to hear better. 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 user, and to create various settings for different listening environments. For example, there can be distinct settings for quiet locations like libraries, for busy restaurants, and for large areas such as sports stadiums.
Digital hearing aids, because of their capacity to manipulate the sounds in digital form, generally offer more features and flexibility, and are often user-configurable. They have an array of memories in which to save more location-specific settings than analog hearing aids. They can also use sophisticated rules to detect and minimize background noise, to eliminate feedback and whistling, or to selectively detect the sound of human voices and “follow” them using directional microphones.
Cost-wise, most analog hearing aids are still less expensive than digital hearing aids, but some reduced-feature digital hearing aids fall into the same general price range. Some users detect a difference in the sound quality generated by analog vs digital hearing aids, but that is largely a matter of personal preference, not really a matter of whether analog or digital is “better.”