When trying to fully understand the difference between analog and digital hearing aids, you need to first understand the history of analog versus digital, and the different ways that they amplify and process sounds. Analog hearing aids came out first, and were the standard in the majority of hearing aids for a long time. Then with the introduction of digital signal processing (DSP) technology, digital hearing aids also started to appear. The majority of (up to 90%) hearing aids purchased in the US today are digital, although you can still find analog hearing aids because some people have a preference for them, and they’re typically less expensive.
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, delivering louder versions of the sound waves to the speakers in your ears “as is.” On the other hand, digital hearing aids utilize the same sound waves from the microphone, but before amplifying them they turn them into the binary code of “bits and bytes” that all digital devices and computers use. Once the sound is digitized, the microchip within the hearing aid can process and manipulate the data in complex ways before converting it back into analog sound and passing it on to your ears.
Both analog and digital hearing aids perform the same work – they take sounds and amplify them to allow you to hear better. Both varieties of hearing aids can be programmed by the dispensers of the hearing aids to create the sound quality that each user desires, and to develop configurations ideal for different environments. The programmable hearing aids can, for example, have one particular setting for listening in quiet rooms, another for listening in noisy restaurants, and still another for listening in large stadiums.
But beyond programmability, the digital hearing aids generally offer more controls to the wearer, and offer additional features because of their capacity to manipulate the sounds in digital form. They have multiple memories in which to save more environment-specific configurations than analog hearing aids. Other features of digital hearing aids include being able to automatically minimize background noise and remove feedback or whistling, or the ability to prefer the sound of voices over other sounds.
Price-wise, most analog hearing aids are still less expensive than digital hearing aids, however, some reduced-feature digital hearing aids are now in the same general price range. Some users detect a difference in the sound quality generated by analog vs digital hearing aids, although that is largely a matter of preference, not really a matter of whether analog or digital is “better.”