A bit of history and an explanation of how analog devices work versus how digital devices work is essential to understand the distinctions between analog and digital hearing aids. Analog hearing aids appeared first, and were the standard in the majority of hearing aids for many years. Then with the arrival of digital signal processing (DSP) technology, digital hearing aids also started to appear. At this point, the majority (90%) of the hearing aids sold in the US are digital, although analog hearing aids continue to be offered because they’re often lower priced, and also because some people have a preference for them.
The way that analog hearing aids operate 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.” Digital hearing aids take the sound waves from the microphone and convert them to digital binary code. This digital data can then be altered in numerous sophisticated ways by the microchip inside the hearing aid, before being transformed back into ordinary analog signals and sent to the speakers.
Analog and digital hearing aids perform the same function – they take sounds and boost them to enable you to hear better. Both analog and digital hearing aids can be programmable, meaning that they contain microchips that can be modified to adjust sound quality to match the individual user, and to develop various configurations for different listening environments. As an example, there can be different settings for quiet locations like libraries, for noisy restaurants, and for large areas such as stadiums.
But beyond programmability, the digital hearing aids often offer more controls to the wearer, and have additional features because of their ability to manipulate the sounds in digital form. They have an array of memories in which to store more environment-specific configurations than analog hearing aids. They can also employ sophisticated rules to identify and reduce background noise, to remove feedback and whistling, or to selectively detect the sound of human voices and “follow” them using directional microphones.
In terms of price, analog hearing aids are generally less expensive, although some digital hearing aids are approaching the cost of analog devices by eliminating the more sophisticated features. There is commonly a noticable difference in sound quality, but the question of whether analog or digital is “better” is entirely up to the individual, and the ways that they are used .