CA1196579A - Active attenuation of noise in a closed structure - Google Patents

Active attenuation of noise in a closed structure

Info

Publication number
CA1196579A
CA1196579A CA000442733A CA442733A CA1196579A CA 1196579 A CA1196579 A CA 1196579A CA 000442733 A CA000442733 A CA 000442733A CA 442733 A CA442733 A CA 442733A CA 1196579 A CA1196579 A CA 1196579A
Authority
CA
Canada
Prior art keywords
cancelling
sound waves
sensing means
closed structure
source
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
CA000442733A
Other languages
English (en)
French (fr)
Inventor
Glenn E. Warnaka
John M. Zalas
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Lord Corp
Original Assignee
Lord Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Lord Corp filed Critical Lord Corp
Application granted granted Critical
Publication of CA1196579A publication Critical patent/CA1196579A/en
Expired legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G10—MUSICAL INSTRUMENTS; ACOUSTICS
    • G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
    • G10K11/00—Methods or devices for transmitting, conducting or directing sound in general; Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
    • G10K11/16—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
    • G10K11/175—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general using interference effects; Masking sound
    • G10K11/178—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general using interference effects; Masking sound by electro-acoustically regenerating the original acoustic waves in anti-phase
    • G10K11/1785—Methods, e.g. algorithms; Devices
    • G10K11/17857—Geometric disposition, e.g. placement of microphones
    • G—PHYSICS
    • G10—MUSICAL INSTRUMENTS; ACOUSTICS
    • G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
    • G10K11/00—Methods or devices for transmitting, conducting or directing sound in general; Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
    • G10K11/16—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
    • G10K11/175—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general using interference effects; Masking sound
    • G10K11/178—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general using interference effects; Masking sound by electro-acoustically regenerating the original acoustic waves in anti-phase
    • G10K11/1785—Methods, e.g. algorithms; Devices
    • G10K11/17853—Methods, e.g. algorithms; Devices of the filter
    • G10K11/17854—Methods, e.g. algorithms; Devices of the filter the filter being an adaptive filter
    • G—PHYSICS
    • G10—MUSICAL INSTRUMENTS; ACOUSTICS
    • G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
    • G10K11/00—Methods or devices for transmitting, conducting or directing sound in general; Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
    • G10K11/16—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
    • G10K11/175—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general using interference effects; Masking sound
    • G10K11/178—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general using interference effects; Masking sound by electro-acoustically regenerating the original acoustic waves in anti-phase
    • G10K11/1787—General system configurations
    • G10K11/17879—General system configurations using both a reference signal and an error signal
    • G—PHYSICS
    • G10—MUSICAL INSTRUMENTS; ACOUSTICS
    • G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
    • G10K11/00—Methods or devices for transmitting, conducting or directing sound in general; Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
    • G10K11/16—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
    • G10K11/175—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general using interference effects; Masking sound
    • G10K11/178—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general using interference effects; Masking sound by electro-acoustically regenerating the original acoustic waves in anti-phase
    • G10K11/1787—General system configurations
    • G10K11/17879—General system configurations using both a reference signal and an error signal
    • G10K11/17881—General system configurations using both a reference signal and an error signal the reference signal being an acoustic signal, e.g. recorded with a microphone
    • G—PHYSICS
    • G10—MUSICAL INSTRUMENTS; ACOUSTICS
    • G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
    • G10K2210/00—Details of active noise control [ANC] covered by G10K11/178 but not provided for in any of its subgroups
    • G10K2210/10—Applications
    • G10K2210/128—Vehicles
    • G10K2210/1281—Aircraft, e.g. spacecraft, airplane or helicopter
    • G—PHYSICS
    • G10—MUSICAL INSTRUMENTS; ACOUSTICS
    • G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
    • G10K2210/00—Details of active noise control [ANC] covered by G10K11/178 but not provided for in any of its subgroups
    • G10K2210/30—Means
    • G10K2210/301—Computational
    • G10K2210/3032—Harmonics or sub-harmonics
    • G—PHYSICS
    • G10—MUSICAL INSTRUMENTS; ACOUSTICS
    • G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
    • G10K2210/00—Details of active noise control [ANC] covered by G10K11/178 but not provided for in any of its subgroups
    • G10K2210/30—Means
    • G10K2210/301—Computational
    • G10K2210/3046—Multiple acoustic inputs, multiple acoustic outputs
    • G—PHYSICS
    • G10—MUSICAL INSTRUMENTS; ACOUSTICS
    • G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
    • G10K2210/00—Details of active noise control [ANC] covered by G10K11/178 but not provided for in any of its subgroups
    • G10K2210/30—Means
    • G10K2210/321—Physical
    • G10K2210/3214—Architectures, e.g. special constructional features or arrangements of features
    • G—PHYSICS
    • G10—MUSICAL INSTRUMENTS; ACOUSTICS
    • G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
    • G10K2210/00—Details of active noise control [ANC] covered by G10K11/178 but not provided for in any of its subgroups
    • G10K2210/30—Means
    • G10K2210/321—Physical
    • G10K2210/3216—Cancellation means disposed in the vicinity of the source
    • G—PHYSICS
    • G10—MUSICAL INSTRUMENTS; ACOUSTICS
    • G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
    • G10K2210/00—Details of active noise control [ANC] covered by G10K11/178 but not provided for in any of its subgroups
    • G10K2210/30—Means
    • G10K2210/321—Physical
    • G10K2210/3219—Geometry of the configuration

Landscapes

  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Acoustics & Sound (AREA)
  • Multimedia (AREA)
  • Soundproofing, Sound Blocking, And Sound Damping (AREA)
CA000442733A 1982-12-15 1983-12-07 Active attenuation of noise in a closed structure Expired CA1196579A (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US449,851 1982-12-15
US06/449,851 US4562589A (en) 1982-12-15 1982-12-15 Active attenuation of noise in a closed structure

Publications (1)

Publication Number Publication Date
CA1196579A true CA1196579A (en) 1985-11-12

Family

ID=23785746

Family Applications (1)

Application Number Title Priority Date Filing Date
CA000442733A Expired CA1196579A (en) 1982-12-15 1983-12-07 Active attenuation of noise in a closed structure

Country Status (6)

Country Link
US (1) US4562589A (https=)
JP (1) JPS59114597A (https=)
CA (1) CA1196579A (https=)
DE (1) DE3344910C2 (https=)
FR (1) FR2538149A1 (https=)
GB (1) GB2132053A (https=)

Families Citing this family (89)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2160742B (en) * 1984-06-21 1988-02-03 Nat Res Dev Damping for directional sound cancellation
US4677677A (en) * 1985-09-19 1987-06-30 Nelson Industries Inc. Active sound attenuation system with on-line adaptive feedback cancellation
US4689821A (en) * 1985-09-23 1987-08-25 Lockheed Corporation Active noise control system
US4829590A (en) * 1986-01-13 1989-05-09 Technology Research International, Inc. Adaptive noise abatement system
US4677676A (en) * 1986-02-11 1987-06-30 Nelson Industries, Inc. Active attenuation system with on-line modeling of speaker, error path and feedback pack
US4715559A (en) * 1986-05-15 1987-12-29 Fuller Christopher R Apparatus and method for global noise reduction
JPS635696A (ja) * 1986-06-26 1988-01-11 Mitsui Eng & Shipbuild Co Ltd 能動防音装置の制御方法
GB2203016A (en) * 1986-10-07 1988-10-05 Adaptive Control Ltd Active sound control apparatus
US4736431A (en) * 1986-10-23 1988-04-05 Nelson Industries, Inc. Active attenuation system with increased dynamic range
GB8704314D0 (en) * 1987-02-24 1987-04-01 Scient Generics Ltd Noise attenuation
US4947435A (en) * 1988-03-25 1990-08-07 Active Noise & Vibration Tech Method of transfer function generation and active noise cancellation in a vibrating system
US4977600A (en) * 1988-06-07 1990-12-11 Noise Cancellation Technologies, Inc. Sound attenuation system for personal seat
GB8820922D0 (en) * 1988-09-06 1988-10-05 Topexpress Ltd Noise reduction in vehicles cabins
JP2748626B2 (ja) * 1989-12-29 1998-05-13 日産自動車株式会社 能動型騒音制御装置
US5125241A (en) * 1990-03-12 1992-06-30 Kabushiki Kaisha Toshiba Refrigerating apparatus having noise attenuation
US5386472A (en) * 1990-08-10 1995-01-31 General Motors Corporation Active noise control system
US5233540A (en) * 1990-08-30 1993-08-03 The Boeing Company Method and apparatus for actively reducing repetitive vibrations
US5245552A (en) * 1990-10-31 1993-09-14 The Boeing Company Method and apparatus for actively reducing multiple-source repetitive vibrations
US5161196A (en) * 1990-11-21 1992-11-03 Ferguson John L Apparatus and method for reducing motion sickness
US5224168A (en) * 1991-05-08 1993-06-29 Sri International Method and apparatus for the active reduction of compression waves
US5310137A (en) * 1992-04-16 1994-05-10 United Technologies Corporation Helicopter active noise control system
US5386689A (en) * 1992-10-13 1995-02-07 Noises Off, Inc. Active gas turbine (jet) engine noise suppression
US5732143A (en) * 1992-10-29 1998-03-24 Andrea Electronics Corp. Noise cancellation apparatus
US5332061A (en) * 1993-03-12 1994-07-26 General Motors Corporation Active vibration control system for attenuating engine generated vibrations in a vehicle
FR2704084B1 (fr) * 1993-04-14 1995-06-23 Matra Sep Imagerie Inf Installation d'insonorisation active pour véhicule de transport collectif.
GB2279778B (en) * 1993-05-19 1997-06-04 Samsung Electronics Co Ltd Vacuum cleaner
US5394376A (en) * 1993-12-17 1995-02-28 Martin Marietta Corporation Method and apparatus for acoustic attenuation
US5660255A (en) * 1994-04-04 1997-08-26 Applied Power, Inc. Stiff actuator active vibration isolation system
US5487027A (en) * 1994-05-18 1996-01-23 Lord Corporation Process and apparatus for providing an analog waveform synchronized with an input signal
US5619581A (en) * 1994-05-18 1997-04-08 Lord Corporation Active noise and vibration cancellation system
US5551650A (en) * 1994-06-16 1996-09-03 Lord Corporation Active mounts for aircraft engines
US5627896A (en) * 1994-06-18 1997-05-06 Lord Corporation Active control of noise and vibration
US5494131A (en) * 1994-07-05 1996-02-27 Ford Motor Company Method and apparatus for damping vibrations in an automotive vehicle having a convertible roof
US5418858A (en) * 1994-07-11 1995-05-23 Cooper Tire & Rubber Company Method and apparatus for intelligent active and semi-active vibration control
US6137886A (en) * 1994-07-18 2000-10-24 Cooper Tire & Rubber Company Active vibration control method and apparatus
US5745580A (en) * 1994-11-04 1998-04-28 Lord Corporation Reduction of computational burden of adaptively updating control filter(s) in active systems
US6343127B1 (en) * 1995-09-25 2002-01-29 Lord Corporation Active noise control system for closed spaces such as aircraft cabin
US5901231A (en) 1995-09-25 1999-05-04 Noise Cancellation Technologies, Inc. Piezo speaker for improved passenger cabin audio systems
US5666427A (en) * 1995-09-30 1997-09-09 Samsung Heavy Industries Co. Ltd. Method of and apparatus for controlling noise generated in confined spaces
US6082084A (en) * 1995-11-13 2000-07-04 Ransomes America Corporation Electric riding mower with electric steering system
US5710714A (en) * 1995-11-15 1998-01-20 Applied Power Inc. Electronic controller for an adaptively tuned vibration absorber
US5920173A (en) * 1995-11-15 1999-07-06 Applied Power Inc. Feedback enhanced adaptively tuned vibration absorber
US5695027A (en) * 1995-11-15 1997-12-09 Applied Power Inc. Adaptively tuned vibration absorber
US5623095A (en) * 1995-11-24 1997-04-22 The United States Of America As Represented By The Department Of Energy Method for chemically analyzing a solution by acoustic means
US5802184A (en) * 1996-08-15 1998-09-01 Lord Corporation Active noise and vibration control system
US5845236A (en) * 1996-10-16 1998-12-01 Lord Corporation Hybrid active-passive noise and vibration control system for aircraft
JPH10184747A (ja) * 1996-12-19 1998-07-14 Sumitomo Electric Ind Ltd 車両ブレーキ用制振装置
US6151397A (en) * 1997-05-16 2000-11-21 Motorola, Inc. Method and system for reducing undesired signals in a communication environment
WO1999005998A1 (en) 1997-07-29 1999-02-11 Telex Communications, Inc. Active noise cancellation aircraft headset system
US6138947A (en) * 1997-08-22 2000-10-31 Sikorsky Aircraft Corporation Active noise control system for a defined volume
FR2769396B1 (fr) * 1997-10-02 2000-11-10 Eurocopter France Dispositif pour reduire le bruit de raies a l'interieur d'un aeronef a voilure tournante, notamment un helicoptere
DE19749587C1 (de) * 1997-11-10 1999-06-24 Daimler Benz Ag Verfahren und Vorrichtung zur Beeinflussung eines von einem Insassen eines Fahrzeuges, insbesondere eines PKW's, subjektiv wahrgenommenen Eindrucks beim Betreiben des Kraftfahrzeugs
US6105900A (en) * 1997-12-23 2000-08-22 Sikorsky Aircraft Corporation Active noise control system for a helicopter gearbox mount
US6042533A (en) * 1998-07-24 2000-03-28 Kania; Bruce Apparatus and method for relieving motion sickness
US6181797B1 (en) 1999-01-09 2001-01-30 Noise Cancellation Technologies, Inc. Piezo speaker for improved passenger cabin audio systems
US6363345B1 (en) 1999-02-18 2002-03-26 Andrea Electronics Corporation System, method and apparatus for cancelling noise
US6283406B1 (en) * 1999-09-10 2001-09-04 Gte Service Corporation Use of flow injection and extraction to control blade vortex interaction and high speed impulsive noise in helicopters
US6594367B1 (en) 1999-10-25 2003-07-15 Andrea Electronics Corporation Super directional beamforming design and implementation
US6443913B1 (en) 2000-03-07 2002-09-03 Bruce Kania Apparatus and method for relieving motion sickness
US6832973B1 (en) 2000-07-21 2004-12-21 William A. Welsh System for active noise reduction
US7367422B2 (en) * 2004-05-21 2008-05-06 Brookstone Purchasing. Inc. System and method for providing passive noise reduction
DE102004041214B4 (de) * 2004-08-26 2006-07-06 Helmut-Schmidt-Universität Universität der Bundeswehr Hamburg Vorrichtung zur Schallminderung von Lärmquellen in schmalen Frequenzbereichen
EP1630788B1 (en) * 2004-08-26 2012-04-18 Airbus Operations GmbH Device and method for reducing sound of a noise source in narrow frequency ranges
US7392869B2 (en) 2005-11-01 2008-07-01 Textron Inc. Modular power source for riding mower
US8302456B2 (en) 2006-02-23 2012-11-06 Asylum Research Corporation Active damping of high speed scanning probe microscope components
JP4857897B2 (ja) * 2006-05-12 2012-01-18 日産自動車株式会社 騒音制御方法および騒音制御装置
US7854293B2 (en) 2007-02-20 2010-12-21 Textron Innovations Inc. Steering operated by linear electric device
US8521384B2 (en) 2008-01-28 2013-08-27 Textron Innovations Inc. Turf maintenance vehicle all-wheel drive system
US20110208361A1 (en) * 2008-09-06 2011-08-25 Hildebrand Stephen F Motion control system with digital processing link
JP2010249800A (ja) * 2009-03-25 2010-11-04 Aisan Ind Co Ltd レゾルバ
WO2011052088A1 (ja) * 2009-11-02 2011-05-05 三菱電機株式会社 騒音制御システム、並びに、それを搭載したファン構造体及び空気調和機の室外機
US8737634B2 (en) 2011-03-18 2014-05-27 The United States Of America As Represented By The Secretary Of The Navy Wide area noise cancellation system and method
DE102011109843A1 (de) * 2011-08-09 2013-02-14 Vaillant Gmbh Kraft-Wärme-Kopplungsanlage
US9827658B2 (en) 2012-05-31 2017-11-28 Black & Decker Inc. Power tool having latched pusher assembly
US11229995B2 (en) 2012-05-31 2022-01-25 Black Decker Inc. Fastening tool nail stop
EP3091415B1 (en) * 2013-08-16 2018-08-01 Kevin Allan Dooley Inc. Systems and methods for control of infrasound pressures
US10048151B2 (en) 2013-08-16 2018-08-14 Kevin Allan Dooley, Inc. Systems and methods for control of motion sickness within a moving structure due to infrasound pressures
US10022848B2 (en) 2014-07-28 2018-07-17 Black & Decker Inc. Power tool drive mechanism
US12502756B2 (en) 2013-10-09 2025-12-23 Black & Decker Inc. High inertia driver system
US9383388B2 (en) 2014-04-21 2016-07-05 Oxford Instruments Asylum Research, Inc Automated atomic force microscope and the operation thereof
US10717179B2 (en) 2014-07-28 2020-07-21 Black & Decker Inc. Sound damping for power tools
US9442496B1 (en) 2015-09-18 2016-09-13 Amazon Technologies, Inc. Active airborne noise abatement
CN105416604B (zh) * 2015-12-14 2018-12-04 深圳市多尼卡航空电子有限公司 一种飞机及其机舱降噪方法和装置
US20170361443A1 (en) 2016-06-20 2017-12-21 Black & Decker Inc. Cylindrical Integrated Valve Assembly
WO2018089345A1 (en) 2016-11-08 2018-05-17 Andersen Corporation Active noise cancellation systems and methods
EP3379529A1 (en) * 2017-03-21 2018-09-26 RUAG Schweiz AG Active noise control system in an aircraft and method to reduce the noise in the aircraft
EP3788619A1 (en) 2018-05-04 2021-03-10 Andersen Corporation Multiband frequency targeting for noise attenuation
CN114201819B (zh) * 2021-12-06 2024-01-12 南京航空航天大学 一种融合声阵列和在桨控制的直升机主动噪声抑制装置
US11664004B1 (en) * 2022-11-09 2023-05-30 Gulfstream Aerospace Corporation Active noise cancellation of tonal noise by manipulating characteristic acoustic modes

Family Cites Families (18)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2361071A (en) * 1942-09-23 1944-10-24 Stevenson Jordan & Harrison In Vibration dampening
US2983790A (en) * 1953-04-30 1961-05-09 Rca Corp Electronic sound absorber
DE2009105A1 (de) * 1970-02-26 1971-09-02 Messerschmitt Boelkow Blohm Larmminderung bei Propellertriebwerken
JPS5062001A (https=) * 1973-09-30 1975-05-27
US4025724A (en) * 1975-08-12 1977-05-24 Westinghouse Electric Corporation Noise cancellation apparatus
GB1577322A (en) * 1976-05-13 1980-10-22 Bearcroft R Active attenuation of recurring vibrations
GB1555760A (en) * 1976-09-27 1979-11-14 Chaplin G B B Active methods for attenuating compression waves
JPS545402A (en) * 1977-06-14 1979-01-16 Jinichi Nishiwaki Low frequency silencer
GB2054999B (en) * 1979-06-28 1983-09-07 Nat Res Dev Signal processing systems
DE3066842D1 (en) * 1979-08-16 1984-04-12 Sound Attenuators Ltd A method of reducing the adaption time in the cancellation of repetitive vibration
US4489441A (en) * 1979-11-21 1984-12-18 Sound Attenuators Limited Method and apparatus for cancelling vibration
EP0040462A1 (en) * 1980-05-16 1981-11-25 Bose Corporation Electroacoustical audible noise reducing apparatus
JPS5726897A (en) * 1980-07-23 1982-02-13 Daikin Ind Ltd Noise erasing device
US4473906A (en) * 1980-12-05 1984-09-25 Lord Corporation Active acoustic attenuator
GB2069280B (en) * 1981-01-05 1984-02-22 Ross C F Process of testing for a sound control system
GB2097629B (en) * 1981-04-15 1984-09-26 Nat Res Dev Methods and apparatus for active sound control
ZA825676B (en) * 1981-08-11 1983-06-29 Sound Attenuators Ltd Method and apparatus for low frequency active attennuation
GB2107960B (en) * 1981-10-21 1985-09-18 George Brian Barrie Chaplin Method and apparatus for cancelling vibrations

Also Published As

Publication number Publication date
GB2132053A (en) 1984-06-27
US4562589A (en) 1985-12-31
JPH0519160B2 (https=) 1993-03-15
DE3344910C2 (de) 1994-09-29
DE3344910A1 (de) 1984-06-20
JPS59114597A (ja) 1984-07-02
GB8332469D0 (en) 1984-01-11
FR2538149A1 (fr) 1984-06-22

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