Patent ID: 9275628
Filing Date: 2016-03-01
CPC Classification: G10K

Claim Text:
1. An acoustic structure for dampening sound generated by a sound source in an enclosed volume, comprising: an acoustic absorber attached to the enclosed volume and having a horn-shaped acoustic element for absorbing the sound generated by the sound source in a certain frequency range, wherein a cross-sectional area of the acoustic element exponentially tapers and decreases with a distance from a mouth of the acoustic element to a throat of the acoustic element: an acoustic radiator having an acoustic element for radiating sound, the acoustic radiator disposed outside the enclosed volume; and one or more acoustic waveguide duets at least partially lined with acoustic absorbing material and configured to acoustically couple the acoustic absorber and the acoustic radiator, wherein a portion of sound inside the enclosed volume is absorbed by the acoustic absorber, dampening the sound in the enclosed volume; wherein the absorbed portion of the sound, at an absorbed sound level is propagated through the one or more acoustic waveguide ducts to the acoustic radiator; and wherein the acoustic absorbing material at least partially lining the one or more acoustic waveguide ducts dampens the portion of the sound absorbed by the acoustic absorber and propagated in the one or more acoustic waveguide ducts resulting in a radiated sound level at the acoustic radiator that is less than the absorbed sound level at the acoustic absorber; further comprising an anti-noise source acoustically coupled to the one or more acoustic waveguide ducts and configured for learning and then generating a cancelling sound 180° out of phase with a first sound generated by a noise source present in the volume, the cancelling sound generated to attenuate and/or substantially cancel the first sound in the one or more acoustic waveguide ducts.