To understand the difference between analog and digital hearing aids, you need to first appreciate the history of analog vs digital, and the alternative ways that they process and amplify sounds. Historically, analog technology appeared first, and consequently most hearing aids were analog until digital signal processing (DSP) was developed, after which digital hearing aids appeared. Currently, the majority (90%) of the hearing aids purchased in the US are digital, although analog hearing aids are still sold because they are often less expensive, and also because some people have a preference for them.
Analog hearing aids handle inbound sounds by taking the electrical sound waves as they leave a microphone and amplifying them “as is” before sending the sound waves to the speakers in your ears. In contrast, 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 ones and zeros that all digital devices understand. This digital information can then be altered in many complex ways by the micro-chip within the hearing aid, prior to being converted back into regular analog signals and sent to the speakers.
Remember that both analog and digital hearing aids have the same function – they take sounds and boost them so that you can hear them more easily. Both analog and digital hearing aids can be programmable, which means that they contain microchips that can be modified to adjust sound quality to suit the user, and to create various settings for different environments. For example, there can be different settings for low-noise locations like libraries, for noisy restaurants, and for outdoor spaces like stadiums.
Digital hearing aids, because of their ability to manipulate the sounds in digital form, generally offer more features and flexibility, and are commonly user-configurable. For example, digital hearing aids may offer numerous channels and memories, allowing them to store more environment-specific profiles. Other features of digital hearing aids include the ability to automatically reduce background noise and remove feedback or whistling, or the ability to prefer the sound of human voices over other sounds.
Price-wise, most analog hearing aids continue to be less expensive than digital hearing aids, however, some reduced-feature digital hearing aids fall into the same general price range. There is often a noticable difference in sound quality, but the question of whether analog or digital is “better” is up to the wearer, and the ways that they are used to hearing sounds.