A Noise Helmet

A helmet‐like enclosure has been developed which generates high‐intensity sound fields about the head of the wearer. A cylindrical chamber with a loudspeaker in the top is mounted on the subject by attaching it to football shoulder‐pads. A cooling blower, a window, and fill‐in material are provided. 130 db over‐all noise levels have been obtained with 6 watts of audio power. Although originally conceived as a portable demonstration apparatus, the device has the advantages of being able to generate high sound levels inexpensively and to facilitate experiments involving communication from one kind of noise field to another. The original model was constructed on U. S. Army Signal Corps contract No. DA 36‐039‐sc‐64469.