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An acoustic structure and a method for dampening sound. The acoustic structure includes an acoustic absorber having one or more acoustic elements. The acoustic absorber is disposed inside a volume. The acoustic structure further includes an acoustic radiator having one or more acoustic elements. The

An acoustic structure and a method for dampening sound. The acoustic structure includes an acoustic absorber having one or more acoustic elements. The acoustic absorber is disposed inside a volume. The acoustic structure further includes an acoustic radiator having one or more acoustic elements. The acoustic radiator is disposed outside the volume. A cross-sectional area of the one or more acoustic elements decreases with a distance from a mouth of the one or more acoustic elements to a throat of the one or more acoustic elements. The acoustic structure also includes one or more acoustic waveguide ducts configured to acoustically couple the acoustic absorber and the acoustic radiator.

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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 cro

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. 2. The structure of claim 1, wherein the volume is a room. 3. The structure of claim 1, wherein the acoustic absorber includes a plurality of acoustic elements which are arranged in a linear or matrix fashion. 4. The structure of claim 1, wherein the acoustic radiator includes a plurality of acoustic elements which are arranged in a linear or matrix fashion. 5. The structure of claim 1, wherein the acoustic element of the acoustic absorber is configured to propagate sound waves from the mouth to the throat when a frequency is greater than a cutoff frequency, the cutoff frequency being equal to approximately 90 m Hz, where m is a flaring parameter in units per foot. 6. The structure of claim 1, wherein a size of the mouth and the size of the throat are selected so that the acoustic absorber absorbs sounds of frequencies greater than a desired cutoff frequency and the acoustic radiator radiates the sounds of frequencies greater than the desired cutoff frequency. 7. The structure of claim 1, wherein the acoustic frequency filter is acoustically coupled to the acoustic radiator via the one or more acoustic waveguide ducts. 8. The structure of claim 1, further comprising an acoustic frequency filter acoustically coupled to the one or more acoustic waveguide ducts. 9. The structure of claim 1, wherein the acoustic radiator and the acoustic absorber are configured so as to minimize or substantially eliminate acoustic distortion effects in the volume. 10. The structure of claim 1, wherein the one or more acoustic waveguide duct is positioned between a wall of a first room and a wall of a second room within the first room. 11. The structure of claim 10, wherein the one or more acoustic waveguide extends through a gap between a ceiling of the second room and the floor of the first room. 12. The structure of claim 10, wherein at least a portion of the wall of the first room is covered with sound insulating material. 13. The structure of claim 10, wherein the one or more acoustic elements of the acoustic absorber is located inside the second room and the one or more cone-shaped acoustic elements of the acoustic radiator is located outside the first room. 14. The structure of claim 13, wherein the one or more acoustic elements of the acoustic absorber is bordered on one side by the ceiling of the second room and on another side by a floor of the second room. 15. The structure of claim 13, wherein the one or more acoustic elements of the acoustic absorber is attached to a ceiling of the second room and is bordered by vertical walls of the second room. 16. The structure of claim 1, wherein the one or more acoustic waveguide ducts comprises a plurality of linked waveguide duct elements. 17. The structure of claim 16, wherein the one or more of the plurality of waveguide duct elements includes a solid body having one or more channels therethrough. 18. The structure of claim 17, wherein the solid body has a lateral opening configured to receive a neck portion of one acoustic waveguide duct element. 19. The structure of claim 17, wherein the one or more channels is open on both ends or closed on one end and open on the other end. 20. The structure of claim 17, wherein the one or more channels is lined with an acoustic liner. 21. The structure of claim 17, wherein one or more acoustic waveguide duct element in the plurality of acoustic waveguide duct elements includes a neck portion. 22. The structure of claim 21, wherein the neck portion extends from the solid body, wherein the neck portion is configured to connect one acoustic waveguide duct element to another acoustic waveguide duct element. 23. The structure of claim 1, further comprising an acoustic frequency filter acoustically coupled to the one or more acoustic waveguide ducts. 24. The structure of claim 23, wherein acoustic frequency filter is a frequency tunable Helmholtz resonator. 25. The structure of claim 23, wherein the acoustic frequency filter is configured to attenuate acoustic resonance frequencies in the one or more acoustic waveguide ducts. 26. The structure of claim 1, wherein the anti-noise source is positioned inside or in the vicinity of the one or more acoustic waveguide ducts. 27. The structure of claim 26, wherein the anti-noise source is controlled by a phase controller or digital signal processing controller configured to sense and learn the phase of the first sound emitted by the noise source and to control the anti-noise source to generate the cancelling sound. 28. The structure of claim 27, further comprising a sound pickup device disposed inside the volume and configured to detect, learn, and communicate the first sound emitted by the sound source to the phase controller or digital signal processing controller. 29. The structure of claim 28, further comprising one or more sound pickup devices disposed inside or in a vicinity of the one or more acoustic waveguide ducts, the one or more sound pickup devices in communication with the phase controller or digital signal processing controller and configured to provide a feedback to the phase controller or digital signal processing controller on a level of sound detected. 30. A method of attenuating sound in a volume, comprising: disposing an acoustic absorber in or attached to the volume axed having one or more horn-shaped acoustic elements for absorbing sound in a certain frequency range and at an absorbed sound level thereby attenuating the sound in the volume, wherein a cross-sectional area of the one or more acoustic elements exponentially tapers and decreases with a distance from a mouth of the one or more acoustic elements to a throat of the one or more acoustic elements; disposing an acoustic radiator having one or more acoustic elements for radiating sound outside the volume; and coupling acoustically the acoustic absorber and the acoustic radiator using one or more acoustic waveguide ducts at least partially lined with acoustic absorbing material in order to absorb a portion of sound absorbed in the volume by the acoustic absorber at the absorbed sound level, and propagating the absorbed sound through the one or more acoustic waveguide ducts to the acoustic radiator; wherein the acoustic absorbing material at least partially lining the one or more acoustic waveguide ducts attenuates the sound propagated therein 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. 31. The method of claim 30, further comprising coupling acoustically an acoustic frequency filter to the one or more acoustic waveguide ducts. 32. The method of claim 30, further comprising coupling a phase tunable anti-noise source to the one or more acoustic waveguide ducts. 33. The method of claim 32, further comprising tuning the phase tunable anti-noise source to substantially attenuate sound waves in the one or more acoustic waveguide ducts. 34. The method of claim 33, wherein the tuning includes generating a sound having a phase substantially opposite a phase of a sound generated in the volume. 35. An acoustic structure for dampening sound in a volume comprising: an acoustic absorber disposed in or attached to the volume and having one or more horn-shaped acoustic elements for absorbing sound in a certain frequency range and at an absorbed sound level, thereby dampening the sound in the volume, wherein a cross-sectional area of the one or more acoustic elements exponentially tapers and decreases with a distance from a mouth of the one or more acoustic elements to a throat of the one or more acoustic elements; an acoustic radiator for radiating sound, the acoustic radiator disposed outside the volume one or more acoustic waveguide ducts configured to acoustically couple the acoustic absorber and the acoustic radiator and propagate the sound absorbed inside the volume at the absorbed sound level by the acoustic absorber to the acoustic radiator; an acoustic frequency filter acoustically coupled to the one or more acoustic waveguide ducts and configured to attenuate acoustic resonance frequencies of the absorbed soured; wherein the attenuated acoustic resonance frequencies of the absorbed sound effected by the acoustic filter dampens the sound 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.