US Patent 11451891 Moving coil microphone transducer with secondary port

A microphone transducer is provided, the microphone transducer comprising a housing and a transducer assembly supported within the housing and defining an internal acoustic space. The transducer assembly includes a magnet assembly, a diaphragm disposed adjacent the magnet assembly and having a front surface and a rear surface, and a coil attached to the rear surface of the diaphragm and capable of moving relative to the magnet assembly in response to acoustic waves impinging on the front surface. The transducer assembly further includes a primary port establishing acoustic communication between the internal acoustic space and an external cavity at least partially within the housing, and a secondary port located at the front surface of the diaphragm.