The Anatomy of a Modern Hearing Aid — Signal Processing Architecture
A hearing aid is essentially an electroacoustic system composed of four primary components: the microphone, the processor, the receiver, and the power source.
Microphones: Most high-end 2026 models use Dual-Microphone Arrays (Directional and Omnidirectional). These microphones capture sound waves and convert them into electrical signals.
The Digital Signal Processor (DSP): This is the "brain" of the device. It converts the electrical signal into binary data ($0s$ and $1s$), applies complex algorithms to amplify specific frequencies (while suppressing noise), and then converts the data back into an analog electrical signal.
The Receiver (Speaker): This component converts the processed electrical signal back into acoustic sound waves and delivers them into the ear canal.
Power Source: In 2026, Lithium-ion rechargeable technology has largely replaced disposable zinc-air batteries, providing 24+ hours of use on a single charge.