To understand the difference between analog and digital hearing aids, it is important to first appreciate the history of analog vs digital, and the alternative ways that they process and amplify sounds. Analog hearing aids came out first, and were the norm in most hearing aids for many years. Then with the introduction of digital signal processing (DSP) technology, digital hearing aids also began to appear. At the moment, most (90%) of the hearing aids purchased in the US are digital, although analog hearing aids are still offered because they are often lower priced, and also 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 the waves, delivering louder versions of the sound waves to the speakers in your ears “as is.” In contrast, digital hearing aids utilize 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. After the sound has been digitized, the micro-chip inside the hearing aid can manipulate the data in complex ways before converting it back into analog sound and delivering it to your ears.
It is important to remember that both analog and digital hearing aids have the same function – they take sounds and boost them so you can hear them more easily. 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 settings appropriate for different environments. For example, there can be different settings for low-noise rooms like libraries, for noisy restaurants, and for outdoor spaces like stadiums.
Digital hearing aids, due to their capacity to manipulate the sounds in digital form, often have more features and flexibility, and are often user-configurable. For example, digital hearing aids may offer multiple channels and memories, permitting them to store more location-specific profiles. Other features of digital hearing aids include the ability to automatically minimize background noise and eliminate feedback or whistling, or the ability to prefer the sound of human voices over other sounds.
As far as pricing is concerned, analog hearing aids are generally cheaper, although some digital hearing aids are nearing the cost of analog devices by removing the more state-of-the-art features. Some users notice a difference in the sound quality generated by analog versus digital hearing aids, although that is largely a matter of preference, not a matter of whether analog or digital is “better.”