History
1934 - The first patent for a noise control system was granted to inventor Paul Lueg U.S. Patent 2,043,416. The patent described how to cancel sinusoidal tones in ducts by phase-advancing the wave and cancelling arbitrary sounds in the region around a loudspeaker by inverting the polarity.
1950s - With U.S. Patent 2,866,848, U.S. Patent 2,920,138, U.S. Patent 2,966,549 by Lawrence J. Fogel, systems were created to cancel the noise in helicopter and airplane cockpits.
1957 - Willard Meeker developed a paper design and working model of active noise control applied to a circumaural earmuff. This headset had an active attenuation bandwidth of approximately 50-500 Hz, with a maximum attenuation of approximately 20 dB.
1986 - Dick Rutan and Jeana Yeager used prototype headsets built by Bose in their around-the-world flight.
Read more about this topic: Active Noise Control
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