Abstract: A system and method for controlling noise produced by an air handling system is provided. The system includes a source microphone to collect sound measurements from the air handling system and a processor to define a cancellation signal that at least partially cancels out the sound measurements. The system also includes a speaker to generate the cancellation signal. The sound measurements are at least partially canceled out within a region of cancellation. Accordingly, the system further includes a response microphone to collect response sound measurements at the region of cancellation. The processor tunes the cancellation signal based on the response sound measurements.

Abstract: Provided is an information system including an information processing device having an audio output function, and a peripheral device connected to the information processing device. The information processing device includes: a device specifying section for designating the peripheral device; a data obtaining section for obtaining, based on designation results from the device specifying section, operational noise cancellation data being audio data for cancelling operational noise emitted from the peripheral device; and an operational noise canceling section for outputting, by means of the audio output function, the operational noise cancellation data obtained by the data obtaining section.

Abstract: A device for damping of vibrations for an item of equipment comprising a structure to which a first element and a second fragile element having to be protected from the vibrations are coupled. The device comprises first piezoelectric transducer means inserted between the structure and the first element and charged with converting energy of vibration of the structure into electric energy, at least one sensor coupled to the structure and arranged to deliver measurement signals representative of vibrations, control means electrically supplied by the electric energy generated and charged with deducing at least one amplitude of movement to compensate at least partially for the vibration, and to deliver control signals representative of each determined amplitude, and second piezoelectric transducer means inserted between the structure and the second element and charged with converting the control signals into movement to damp at least partially for the second element the vibrations.

Abstract: A computer system includes a chassis with a fan installed therein, a cover plate adapted to be attached to the chassis, and a noise absorber attached to the cover plate. The fan is capable of generating an amount of air flow for cooling at least a component in the chassis. The noise absorber includes a plurality of protrusions facing the fan and capable of damping the air flow that impacts the cover plate and decreasing an acoustic noise level of the computer system.

Abstract: Some demonstrative embodiments include a muffled rack configured to maintain at least one electronic device, wherein the electronic device has an inlet to receive air for cooling the electronic device and an outlet to discharge the air. The muffled rack may be configured to muffle noise emanating from within the rack through an air inlet and/or an air outlet of the rack. Other embodiments are described and claimed.

Abstract: The subject system combines a sound generating controller device with a domestic air conditioning unit. The sound controller synchronises the speed and direction of the airblower and directional airflow vanes, thus being able to simulate a variety of natural environments. The integration of a sound generation device, and the further synchronisation of these sounds with the operation of the airflow speed and directional controls on the air conditioner, are distinguishing features of this system proposal. An active noise canceller is optional, to further eliminate unwanted external noises.

Abstract: Provided is an apparatus and method to control fan noise in a computer server room. An exemplary apparatus includes one or more transducers coupled to one or more walls of a plurality of system racks and one or more active noise control units, wherein the one or more active noise control units send control signals to the one or more transducers to emit a transducer acoustic wave. It also includes a microphone installed near a location in the computer server room where cooling fan noise needs to be controlled, wherein the microphone collects fan noise signals emitted from running fans on the plurality of system racks in the computer server room and sends the collected fan noise signals to the one or more active noise control units to allow the frequency and intensity of the transducer acoustic wave to be substantially equal to a frequency and an intensity of the fan noise and at about 180 degrees out of phase with the fan noise to reduce or to eliminate the fan noise.

Abstract: A display apparatus has a display unit; a housing which accommodates the display unit; a compressor for cooling the air inside the housing; a detecting unit which detects a sound generated from the compressor and an output unit which outputs a sound for canceling the sound detected by the compressor.

Abstract: An analog to digital conversion circuit comprises a first digital noise cancellation filter (16) configured to provide a signal to cancel quantization noise from an analog to digital converted output signal. In a calibration phase a second digital noise cancellation filter (26) is has an input coupled to an input of the first digital noise cancellation filter (16). Mutually different sets of at least one-filter coefficients are programmed in the first and second digital noise canceling filters (16, 26). A difference is computed of averaged size indications of digital output signals derived using signals from the first and second digital noise cancellation filters (16, 26) using the same input signal. Updates of the sets of at least one filter coefficients are adapted dependent on the difference between the averaged size indications.

Abstract: An Active Muffler in the form of a duct having two open ends for conveying air from a within a cabinet to outside the cabinet. A fan or blower is incorporated in the duct. An Automatic Noise Control (ANC) unit is associated with the duct, and at least one microphone and at least one speaker are incorporated in to the duct for noise-reduction. An outer portion of the duct may be sound-absorbing material. the ANC unit may cause noise to be shifted to a frequency that can be absorbed by the sound-absorbing material.

Abstract: An Active Noise Control (ANC) for controlling a noise produced by a noise source may include an acoustic sensor (212) to sense a noise pattern and to produce a noise signal corresponding to the sensed noise pattern, an estimator (202) to produce a predicted noise signal by applying an estimation function to the noise signal, and an acoustic transducer (216) to produce a noise destructive pattern based on the predicted noise signal.

Abstract: Soundproofing a rack by installing at least one duct on at least one panel of the rack, or as part of the side panels of the rack, or is mounted inside the rack as a drawer in such a way that air can flow outside from the rack causing air to flow from the rack through the duct, and providing an active noise control (ANC) system within the duct. Passive noise control may also be provided in the duct. At least one fan may be provided at an inlet of the duct. Fan speed may be controlled, in response to a climactic condition within the rack. The duct may comprise a back panel which is added on or a replacement for an existing back panel of the rack. A muffled inlet may be provided on another external surface of the rack.

Abstract: It includes a microphone for detecting noise emitted from a noise source, a noise controller for generating control sound signal to reduce noise detected by the microphone based on information from the microphone, and a speaker for outputting control sound based on control sound signal from the noise controller, wherein a plurality of microphones and speakers are arranged for each seat, and a plurality of microphones are arranged in higher density for each seat in a specific direction.

Abstract: The present invention provides a method, apparatus, and computer implemented instructions for computer-based onboard noise suppression devices with remote web-based management features. The present invention detects noise within a computer. A noise canceling signal is generated based on parameters. These parameters may include, for example, the percentage of noise to suppress. The noise canceling signal is broadcasted to reduce or eliminate noise. Additionally, the present invention provides the ability to remotely manage noise suppression within computers.

Abstract: Reduction of noise in a device having a console with one or more microphones and a source of narrow band distributed noise located on the console is disclosed. A microphone signal containing a broad band distributed desired sound and narrow band distributed noise is divided amongst a plurality of frequency bins. For each frequency bin, it is determined whether a portion of the signal within the frequency bin belongs to a narrow band distribution characteristic of the source of narrow band noise located on the console. Any frequency bins containing portions of the signal belonging to the narrow band distribution are filtered to reduce the narrow band noise.

Abstract: An active noise control (ANC) system may be implemented to both sides of a fan, such that both directions of the noise emitting are treated to reduce the overall noise. The impact on airflow is minimal, and the technique is very effective in a broad range of low frequencies. Passive sound-absorbing materials may be included for attenuation of high frequencies. The resulting quiet fan produces a low level of noise compared to any other device based on fan, which produces the same capacity of airflow. The quiet fan may be incorporated in any mechanical system which requires airflow induction such as: computers, air conditioners, machines, and more.

Abstract: Disclosed herein are a washing machine and a sound control method thereof that are capable of canceling noise generated during an operation of the washing machine and, at the same time, informing a user of information related to the operation of the washing machine using a sound. The sound control method includes operating the washing machine according to an inputted operation command, sensing noise generated during the operation of the washing machine, reading a sound to cancel the sensed noise, and outputting the read sound in a state in which the read sound is mapped with the noise. Consequently, it is possible mask the noise, thereby minimizing the noise. Also, it is possible to sense a start and an end of each operation and a change of the operation based on the noise pattern, sense a user's access to the washing machine, and output a feedback sound, thereby informing of the progress information of the washing machine.

Abstract: Some embodiments of the present invention provide a system that attenuates noise from a fan exhaust of a computer system. During operation, the system monitors the noise from the fan exhaust and calculates a frequency spectrum of the noise from the monitored noise. Next, the system generates an antiphase spectrum from the frequency spectrum and generates a flow of air which exhibits a property of the antiphase spectrum. Finally, the system directs the flow of air into the fan exhaust so that the noise is attenuated by a reduction of turbulence in the fan exhaust by the flow of air.

Abstract: In a communication machine room wideband noise suppression system, a sensing unit detects a noise source produced by a fan during the operation thereof and generates a noise input signal and a feedback signal, which are sent to a signal amplifying unit for signal amplification. The amplified signals are then sent to a signal converting unit and converted into digital signals. A multi-channel hybrid controller receives the digital signals and makes corrections and conduct rapid convergence algorithm to derive a reverse digital signal, which is sent to the signal converting unit and converted into a reverse analog signal. The reverse analog signal is sent to the signal amplifying unit for power amplification to generate a control signal for driving a loudspeaker unit to produce interfering acoustic wave, so as to cancel out the noise source and achieve the purpose of eliminating wideband noise.

Abstract: A medical device, such as a respiratory treatment device, having an active acoustic noise cancellation system. In one embodiment, the noise minimizing system includes at least one detector detecting characteristics of acoustic noise of a blower assembly and at least one speaker creating a cancellation frequency in the form of acoustic waves that at least partially cancels acoustic waves generated by the blower assembly. In another embodiment, the noise minimizing system includes a mechanical vibration generating element that creates a cancellation frequency in the form of a mechanical vibration that at least partially cancels vibrations of the blower assembly. This is accomplished, for example, by dithering a flow control valve at a frequency corresponding to an operating frequency of the blower assembly. Each embodiment can be used alone or in combination.

Abstract: A noise reduction system for use with noise generating equipment. The system includes at least one sensor to generate one or more input signals, with each input signal being representative of an operating condition of the equipment. The system also includes a signal processing unit in communication each sensor to receive the input signal(s) and to generate at least one anti-noise output signal based on the input signal(s). The system further includes at least one output device in communication with the signal processing unit to generate anti-noise based on an anti-noise output signal. The anti-noise reduces noise emitted by the equipment during operation.

Abstract: An apparatus and method for presenting high-quality auditory stimuli, receiving patient communication and providing noise cancellation within the environment of magnetic resonance imaging (“MRI”) equipment. A microphone is positioned in a noise attenuated channel for recording of the patient's voice. A microphone is disposed outside of a noise attenuated channel to directly record the sounds of MRI equipment during its operation. The signals generated by the microphones are employed to reduce the output of noise generated by MRI equipment.

Abstract: A sound altering apparatus for altering predetermined sound levels of a sound producing device, the sound altering apparatus includes at least one piezoelectric foil sensor disposed relative to the sound producing device with the at least one piezoelectric foil sensor being operable to convert such sound wave energy into an electric sound signal one or more electric circuits in electrical communication with the at least one piezoelectric foil sensor for receiving the electric sound signal and shunting the electric sound signal to a ground connection, or to produce cancelling sound wave energy in the vicinity of the sound producing device, thereby reducing sound heard outside the sound producing device.

Abstract: A passive noise reduction apparatus for altering predetermined sound levels of a sound producing device, the noise reduction apparatus includes at least one piezoelectric foil sensor disposed relative to the sound producing device with the at least one piezoelectric foil sensor being operable to convert such sound wave energy into an electric sound signal and one or more electric circuits in electrical communication with the at least one piezoelectric foil sensor for receiving the electric sound signal and shunting the electric sound signal to a ground connection, thereby reducing sound heard outside the sound producing device.

Abstract: An apparatus for attenuating noise emanating from a cabinet housing noise-generating equipment includes a frame including at least one support member configured to be mountable on the cabinet, proximate the noise-generating equipment, at least one noise attenuation device mounted to each support member proximate the noise-generating equipment, the at least one noise attenuation device comprising a sound input device for receiving a noise signal output from the noise-generating equipment, a processing device for determining characteristics of the noise signal and generating a cancellation signal which is identical to the noise signal but approximately 180 degrees out-of-phase with the noise signal, and a sound output device for outputting the cancellation signal proximate the noise-generating equipment, to attenuate the noise emanating from the cabinet; and a noise absorption member mounted on each support member, the noise absorption members define surfaces that form sides of airflow channels through the appa

Abstract: A system and method of reducing noise in an enclosure is disclosed. The method includes receiving at least one reference signal; receiving pressure signals from no more than two substantially orthogonally placed pairs of acoustic sensors, where one pair of acoustic sensors is in the x-direction and one pair of acoustic sensors is in the y-direction, and where the acoustic sensors are placed in a plane which is substantially parallel and in proximity to an inner surface of the enclosure; using the pressure signals and the reference signal to generate an output signal to minimize energy density at a location of the acoustic sensors; and sending the output signal to an acoustic actuator.

Abstract: A circuit for eliminating abnormal sound includes a video/audio processor, a D/A converter, a front-stage mute circuit, a changing delay device, a front-stage amplifier, a back-stage amplifier, a back-stage mute circuit, and a micro control unit. The circuit is mounted in a display device connected to a DVD player. When DVD player plays the video/audio signal having HDMI standard, the display device will generate an abnormal sound (pop voice or declining voice) during performing an operation such as pause, stop or play. Therefore, this circuit uses the changing delay device, the micro control unit, and the mute circuit to filter out the noise for providing a better outputting quality.

Abstract: An Active Muffler in the form of a duct having two open ends for conveying air from a within a cabinet to outside the cabinet. A fan or blower is incorporated in the duct. An Automatic Noise Control (ANC) unit is associated with the duct, and at least one microphone and at least one speaker are incorporated in to the duct for noise-reduction. An outer portion of the duct may be sound-absorbing material. the ANC unit may cause noise to be shifted to a frequency that can be absorbed by the sound-absorbing material.

Abstract: An active noise reduction system for reducing the acoustic noise generated by a hard disk drive or generated external of a hard disk drive. The active noise reduction system is integrated into the hard disk drive and produces an acoustic waveform that is 180 degrees out-of-phase with the acoustic noise being generated, for example, by the spindle motor and VCM. The acoustic noise is received directly through a microphone or indirectly through the read/write head, spindle motor driver, or VCM driver. The acoustic noise is processed by electronics and the noise canceling waveform is either retrieved from the hard disk drive's memory, disk, or generated by the electronics. The noise canceling waveform is then broadcasted through one or more transducers that are integrated in the hard disk drive.

Abstract: A noise reduction system for use with an exhaust nozzle associated with a jet engine of an aircraft. The noise reduction system employs a plurality of flow-altering components disposed circumferentially about a lip portion of an exhaust nozzle. In one preferred form the flow-altering components each comprise piezoelectric transduction layers. The flow-altering components are caused to move in an oscillating manner by an AC signal applied thereto such that they move into and out of the exhaust gas emitted from the exhaust nozzle to achieve a desired degree of intermixing of the exhaust flow with the flow adjacent the exhaust nozzle. This produces a reduction in the noise generated by the jet engine. The noise reduction can be utilized during takeoff conditions of an aircraft.

Abstract: A speech recognition apparatus including an audio cancellation module is disclosed. The module includes an audio input for receiving an audio signal from a microphone. The module also includes at least two audio inputs for receiving audio signals from respective independent audio sources. The audio cancellation module produces a speech signal by canceling two of the independent audio source signals from the microphone signal. A speech recognizer is used to recognize at least part of the speech signal.

Abstract: A device for use in an audio signal processing system, the device having at least one operating member for processing an audio signal; and a vibration transmission circuit connected to the operating member to distribute undesired vibration in controlled manner.

Abstract: An air moving apparatus for generating cooling airflow is provided that includes a noise reduction system for reducing noise generated by a fan. The air moving apparatus includes a fan having a rotatable hub and a plurality of blades mounted to the hub for rotating about an axis of rotation to provide pressurized airflow. A sensor is situated on a surface of at least one fan blade for sensing airflow characteristics of the air flowing over the fan blade. An actuator, also situated on the surface of the fan blade, changes the characteristic of the airflow over the fan blade in response to the sensed airflow characteristic.

Abstract: A system for sound cancellation includes a source microphone for detecting sound and a speaker for broadcasting a canceling sound with respect to a cancellation location. A computational module is in communication with the source microphone and the speaker. The computational module is configured to receive a signal from the source microphone, identify a cancellation signal using a predetermined adaptive filtering function responsive to acoustics of the cancellation location, and transmit a cancellation signal to the speaker.

Abstract: Two electrical power components used in the course of operating an appliance are configured to operate at frequencies which are out-of-phase with respect to one another such that operating noises produced by the first component are effectively reduced in magnitude based on the operation of the second component. The components can be constituted by multiple pumps, a pump/motor combination, a motor and transformer or the like. Operational vibrations can also be reduced by mounting the components in a cabinet of the appliance through a common bracket.

Abstract: A method of noise value control by controlling the rotation rate of a fan utilizes a set temperature control plot to estimate the noise value of fans and temperature changes of CPUs corresponding to the fans to optimize thermal energy absorption, achieve a suitable noise value, and take less manpower and time.

Abstract: A noise reduction system for use with an exhaust nozzle associated with a jet engine of an aircraft. The noise reduction system employs a plurality of flow-altering components disposed circumferentially about a lip portion of an exhaust nozzle. In one preferred form the flow-altering components each comprise piezoelectric transduction layers. The flow-altering components are caused to move in an oscillating manner by an AC signal applied thereto such that they move into and out of the exhaust gas emitted from the exhaust nozzle to achieve a desired degree of intermixing of the exhaust flow with the flow adjacent the exhaust nozzle. This produces a reduction in the noise generated by the jet engine. The noise reduction can be utilized during takeoff conditions of an aircraft.

Abstract: An active noise cancellation apparatus and method for actively reducing the level of noise generated by an ambient noise source, such as a domestic appliance. This active noise cancellation apparatus has a pickup device (1, 20) to translate the noise into an electrical signal, a buffer amplifier (2, 22) to allow the distribution of those signals to a digital filter section (3) having a series of switched capacitor filters for analyzing and dividing the signal into separate harmonic signals, a dual analog delay line (4) for producing a phase shift in the signals, a summing amplifier (2,6) to recombine the signals into one signal, a power amplifier (5, 27) to drive an output loudspeaker (6, 31) which produces a phase shifted sound wave to cancel the noise generated by the ambient noise source.

Abstract: The invention provides an acoustic cooling system with a noise reduction function of the type wherein a driving condition of a sound source used in the acoustic cooling system is controlled to compress coolant by a sound wave and a cooling object is cooled making use of an endothermic action of the coolant when the compressed coolant is expanded and which can reduce noise produced from the sound source effectively.

Abstract: An active noise reduction system for reducing the acoustic noise generated by a hard disk drive or generated external of a hard disk drive. The active noise reduction system is integrated into the hard disk drive and produces an acoustic waveform that is 180 degrees out-of-phase with the acoustic noise being generated, for example, by the spindle motor and VCM. The acoustic noise is received directly through a microphone or indirectly through the read/write head, spindle motor driver, or VCM driver. The acoustic noise is processed by electronics and the noise canceling waveform is either retrieved from the hard disk drive's memory, disk, or generated by the electronics. The noise canceling waveform is then broadcasted through one or more transducers that are integrated in the hard disk drive.

Abstract: Apparatus for reducing noise emitted from an appliance having a cabinet that supports at least one component that emits at least one acoustic pressure wave therefrom. In a preferred form, the apparatus comprises at least one diffuser having at least one deflection surface. The diffuser is coupled to the cabinet and positioned relative to the one component such that the acoustic pressure wave emitted from the component is deflected by the one deflection surface in a predetermined direction. The diffuser can be used to deflect acoustic pressure waves such that they collide with each other. The apparatus may further include at least one absorber. The diffuser is strategically located to deflect acoustic pressure waves being emitted from the component into the absorber to reduce the noise emitted from the appliance.

Abstract: An apparatus for suppressing an induced intracranial noise or vibrational signal within a patient's head due to a drilling or cutting medical instrument. The apparatus includes a mechanism for sensing the intracranial vibrational signal induced within the patient's head. The apparatus also includes a mechanism for adaptively generating an intracranial vibrational suppression signal from the intracranial vibrational signal as a function of time. In addition, the apparatus provides a mechanism for applying the intracranial vibrational suppression signal to the patient's head for suppressing the induced intracranial noise or vibrational signal.

Abstract: A space 4 constituted by a sound absorption panel section 1 and active sound absorption control system section 2 between the inner and outer walls of a nacelle forming an engine intake/exhaust duct is utilized as an acoustic resonance field and as a sound absorption field by sticking a porous sound absorption material 14 onto the inside wall surface of the space. The panel section 1 defines a sound absorption space by means of surface plate 6 made of a perforated plate and wire mesh materials plate, panel construction side plate 9 and back sheet plate 13 having porous sound absorption material stuck thereon; and a movement-controlled reflective plate 8, that is capable of movement/rotation control with respect to said perforated plate, is provided within this sound absorption space.

Abstract: An apparatus for reducing noise emitted by an electronic or other device and such devices incorporating the noise reducing apparatus. A mechanism for acoustically filtering undesired noise from an electronic device, particularly noise generated by a cooling mechanism is disclosed. In a preferred embodiment, noise is filtered at least in part with an appropriately dimensioned compressible air space. The noise reducing or filtering mechanism may be utilized with portable and non-portable computers, stereos, entertainment equipment and other devices.

Abstract: The invention relates to a monitor comprising a picture tube and an audio part mounted on a base. The picture tube unit (1) of the monitor includes main sound reproduction elements (6, 7) for the production of sound frequencies deviating from the self-resonant frequency. The base (2) comprises a bass unit which is used to reproduce sound frequencies at the self-resonant frequency. Thus, it is possible to dampen the vibration caused by the self resonant frequencies so that these frequencies do not harmfully interfere with the picture display. The invention is applicable especially in connection with a picture tube operating have a fine pitch shadow mask.

Abstract: A fan noise canceller comprises a rotation information detecting means 2 (or 12) for detecting noise information of a fan 1 (11), a band-pass filter 3 (13) for extracting the blade passing frequency from the noise information, an output control means 4 (14) for controlling the amplitude and phase of the blade passing frequency signal of the extracted noise information, and a cancelling loud-speaker 2 (25) for converting the output of the output control means 4 (41) into a sound signal. The rotation information detecting mean 2 (21) Yincludes a rotatable disc 2A coupled to the shaft of the fan 1 (11) and carrying change information corresponding to the number of fan blades, and a photo-interrupter 2B for outputting signals of the blade passing frequency and harmonics thereof contained in the rotation information of the rotatable disc 2A as electric signals.