A bit of history and an explanation of how analog devices work versus how digital devices work is essential to understand the distinctions between digital and analog hearing aids. Historically, analog technology appeared first, and consequently most hearing aids were analog until digital signal processing (DSP) was developed, at which point digital hearing aids appeared. Most (roughly 90%) hearing aids purchased in the US at this point are digital, although you can still get analog hearing aids because some people have a preference for them, and they’re often cheaper.
The way that analog hearing aids work is that they take sound waves from the microphone in the form of electricity and then amplify the waves, sending louder versions of the sound waves to the speakers in your ears “as is.” Digital hearing aids take the sound waves from the microphone and transform them to digital binary code, the “bits and bytes” and “zeros and ones” that all digital devices understand. After the sound has been digitized, the microchip inside the hearing aid can process and manipulate the data in sophisticated ways before converting it back into analog sound and passing it on to the ears.
Both analog and digital hearing aids carry out the same work – they take sounds and boost them to enable you to hear better. Both varieties of hearing aids can be programmed by the dispensers of the hearing aids to produce the sound quality that each user desires, and to create configurations appropriate for different environments. As an example, there might be distinct settings for quiet rooms like libraries, for noisy restaurants, and for outdoor spaces such as sports stadiums.
But beyond programmability, the digital hearing aids generally offer more controls to the wearer, and have more features because of their ability to manipulate the sounds in digital form. They have an array of memories in which to save more location-specific configurations than analog hearing aids. Other capabilities of digital hearing aids include the ability to automatically reduce background noise and eliminate feedback or whistling, or the ability to prefer the sound of voices over other sounds.
As far as pricing is concerned, analog hearing aids are in most cases less expensive, although some digital hearing aids are approaching the cost of analog devices by eliminating the more state-of-the-art features. There is commonly 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.