A bit of background and an explanation of how analog devices work versus how digital devices work is necessary to understand the differences between analog and digital hearing aids. Analog hearing aids came out first, and were the standard in the majority of hearing aids for a long time. Then with the arrival of digital signal processing (DSP) technology, digital hearing aids also started to emerge. Most (roughly 90%) hearing aids purchased in the US today are digital, although you can still get analog hearing aids because some people prefer them, and they are 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 them, sending louder versions of the sound waves to the speakers in your ears “as is.” On the other hand, 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 “bits and bytes” that all digital devices and computers understand. This digital data can then be manipulated in many sophisticated ways by the micro-chip within the hearing aid, prior to being converted back into regular analog signals and sent to the speakers.
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 adjust sound quality to suit the user, and to develop different settings for different environments. The programmable hearing aids can, for instance, have one setting for listening in quiet rooms, another setting for listening in loud restaurants, and still another setting for listening in large stadiums.
But beyond programmability, the digital hearing aids often offer more controls to the user, and have additional features because of their capacity to manipulate the sounds in digital form. For example, digital hearing aids may offer numerous channels and memories, allowing them to store more location-specific profiles. Other capabilities 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.
Cost-wise, most analog hearing aids continue to be less expensive than digital hearing aids, however, some reduced-feature digital hearing aids fall into a similar general price range. There is often a perceivable difference in sound quality, but the question of whether analog or digital is “better” is up to the individual, and the ways that they are used to hearing sounds.