US Patent 10034086 Headset porting

A headset includes at least one ear cup having front and rear cavities separated by a driver. The cup includes a pressure equalization port coupling the front cavity to space outside the cup, the pressure equalization port having a cross-sectional area greater than 2 mm2 and being significantly longer than it is wide, providing a principally reactive acoustic impedance, such that the pressure response of the front cavity including the port to signals input via the driver may be effectively linear over a wide range of pressure levels within the front cavity.