New Earphone Cushion and Mounting System for a Protective Helmet Free

This paper summarizes the development and performance of a friction‐spring earphone cushion, designed to provide improved low‐frequency noise isolation when used within a hard helmet. The cushion is soft and seals well for a low‐static clamping force against the head; but is stiff and provides a relatively rigid support for the earphone enclosure against oscillating forces induced by an external sound field. Also described is a new mounting system for the earphone enclosure that provides excellent vibration isolation and utility.