Which foundational audio engineering innovation underpins devices converting subtle body sounds to electrical signals?

Electret microphone technology

The evolution toward electronic stethoscopes, which move beyond purely mechanical conduction, fundamentally depends on innovations in sound transduction—the method by which acoustic energy is converted into electrical signals. The underlying technology required for such devices to accurately capture and convert subtle body sounds into reliable electrical signals for processing is heavily reliant on innovations within microphone technology. The work associated with figures like Dr. James West, a co-inventor of the electret microphone, represents the type of foundational audio engineering required to bridge the gap between the physical sound waves within the body and the digital domain needed for amplification and analysis.