NOISE REDUCTION

摘要

A wind noise reduction apparatus for being worn in conjunction with a helmet to reduce the level of wind noise perceived by the helmet wearer, said apparatus comprises a microphone (5) for detecting in use the ambient wind noise in the vicinity of the helmet and for producing an electrical output signal, active noise cancellation circuitry (8) responsive to said microphone output signal to produce a noise cancellation signal, and a speaker (4) responsive to said noise cancellation signal to emit a sound tending to reduce in use the level of wind noise perceived by the wearer. The microphone speaker and circuitry are preferably housed in a pouch in an article of headgear designed to be worn under an activity helmet such as a motorcycle helmet.