WO1994017513A1 - Earpiece for active noise cancelling headset - Google Patents

Earpiece for active noise cancelling headset Download PDF

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Publication number
WO1994017513A1
WO1994017513A1 PCT/US1994/000849 US9400849W WO9417513A1 WO 1994017513 A1 WO1994017513 A1 WO 1994017513A1 US 9400849 W US9400849 W US 9400849W WO 9417513 A1 WO9417513 A1 WO 9417513A1
Authority
WO
WIPO (PCT)
Prior art keywords
baffle
shell
sound
earpiece
baffle plate
Prior art date
Application number
PCT/US1994/000849
Other languages
French (fr)
Inventor
Owen Jones
Original Assignee
Active Noise And Vibration Technologies, Inc.
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 Active Noise And Vibration Technologies, Inc. filed Critical Active Noise And Vibration Technologies, Inc.
Priority to AU61274/94A priority Critical patent/AU6127494A/en
Publication of WO1994017513A1 publication Critical patent/WO1994017513A1/en

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
    • H04R1/00—Details of transducers, loudspeakers or microphones
    • H04R1/10—Earpieces; Attachments therefor ; Earphones; Monophonic headphones
    • H04R1/1083—Reduction of ambient noise
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61F—FILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, e.g. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS
    • A61F11/00—Methods or devices for treatment of the ears or hearing sense; Non-electric hearing aids; Methods or devices for enabling ear patients to achieve auditory perception through physiological senses other than hearing sense; Protective devices for the ears, carried on the body or in the hand
    • A61F11/06—Protective devices for the ears
    • A61F11/14—Protective devices for the ears external, e.g. earcaps or earmuffs
    • A61F11/145—Protective devices for the ears external, e.g. earcaps or earmuffs electric, e.g. for active noise reduction
    • 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
    • G10K11/17861—Methods, e.g. algorithms; Devices using additional means for damping sound, e.g. using sound absorbing panels
    • 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
    • G10K11/17875—General system configurations using an error signal without a reference signal, e.g. pure feedback
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M1/00—Substation equipment, e.g. for use by subscribers
    • H04M1/02—Constructional features of telephone sets
    • H04M1/19—Arrangements of transmitters, receivers, or complete sets to prevent eavesdropping, to attenuate local noise or to prevent undesired transmission; Mouthpieces or receivers specially adapted therefor
    • 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
    • G10K2210/106—Boxes, i.e. active box covering a noise source; Enclosures
    • 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
    • G10K2210/108—Communication systems, e.g. where useful sound is kept and noise is cancelled
    • G10K2210/1081—Earphones, e.g. for telephones, ear protectors or headsets
    • 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
    • G10K2210/3224—Passive absorbers
    • 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
    • G10K2210/50—Miscellaneous
    • G10K2210/509—Hybrid, i.e. combining different technologies, e.g. passive and active
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
    • H04R1/00—Details of transducers, loudspeakers or microphones
    • H04R1/10—Earpieces; Attachments therefor ; Earphones; Monophonic headphones
    • H04R1/1008—Earpieces of the supra-aural or circum-aural type
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
    • H04R5/00—Stereophonic arrangements
    • H04R5/033—Headphones for stereophonic communication

Definitions

  • the present invention relates to an earpiece for active noise cancellation, and a headset or telephone handset including such an earpiece.
  • a conventional ear defender provides a high degree of high frequency passive attenuation by means of a combination of the mass of the shell and the compliance of the air enclosed by the shell. These elements form a second order low pass filter such that the higher the mass and the larger the enclosed volume, the higher the degree of attenuation.
  • an earphone is mounted on an annular baffle, rigidly fixed inside the shell.
  • the baffle is sealed to the inner surface of the shell and the earphone is mounted across the opening in the baffle to define a sealed volume in the shell.
  • the air volume behind the earphone is isolated from that in front of the earphone and is thereby prevented from contributing to the attenuation at the ear.
  • a normal active ear defender gives poorer high frequency attenuation than a passive ear defender of the same size and weight.
  • a passive ear defender might give 40 to 45 dB attenuation above 1 kHz, whereas an active ear defender gives only 30 dB.
  • active ear defenders to enhance higher frequency noise.
  • an earpiece for an active noise cancellation comprising: a shell covering or holding to a user's ear; a baffle extending across the inside of the shell to define a closed volume therein; and a sound producer mounted on the baffle for directing anti-noise sound towards the user's ear.
  • the baffle is sufficiently compliant to enhance passive attenuation of sound having a frequency above 200 Hz.
  • the baffle comprises a stiff baffle plate and a compliant seal for connecting the baffle plate to the shell.
  • the baffle plate itself may be formed of suitably flexible resilient material.
  • the sound producer includes a moving sound producing diaphragm structure, and the resonant frequency of the baffle is below that of the diaphragm structure in use.
  • a headset for active ear defense comprising: first and second earpieces for respective ears of the user, and a headband coupling earpieces, wherein each earpiece comprises a shell for holding to one of the user's ears; baffle means extending across the shell to define a closed volume therein; and a sound producer mounted on the baffle for directing anti- noise sound towards the user's ear, wherein the baffle is sufficiently compliant to enhance passive attenuation of a sound having a frequency above 200 Hz.
  • an active noise cancelling system comprising an earpiece, a shell for covering or holding to a user's ear, a baffle mans extending across the shell to define a closed volume therein, a sound producer mounted on the baffle, and a microphone, wherein the baffle means is sufficiently compliant to enhance passive attenuation of a sound having frequency above 200 Hz, and an electronic controller for producing signals to drive the sound producer to produce cancelling sound in response to the output of the microphone.
  • Such a system is applicable to a single earpiece handset of a conventional telephone or other headset.
  • a system having two earpieces for a headset is also disclosed.
  • Figure 1 shows a headset according to the present invention
  • Figure 2 shows a cross-sectional view of an earpiece according to the present invention
  • Figure 3 shows a telephone handset according to the present invention.
  • an active ear defender comprising a pair of earpieces 1 coupled by a headband 2.
  • An electronic control unit 3 monitors the sound in the earpieces and sends drive signals to a sound producer (not shown) mounted in each earpiece to produce cancelling sound.
  • the cancelling sound destructively interferes with incident noise to achieve quieting in the earpieces 1.
  • a suitable electronic control unit 3 is disclosed in PCT Application No. GB92/01399.
  • the earpiece 1 is shown comprising a cup-shaped shell 4, having a radially inwardly extending lip 4a, an annular cushion 5 supported on the lip 4a, a rigid annular baffle plate 6, supported by an annular compliant seal 7 affixed to the inner surface of the shell 4, a small speaker or earphone 8 (hereinafter referred to as an earphone) mounted on the baffle plate 6 across the central opening therein and a microphone 9 located on the ear side of the baffle plate 6.
  • the compliant seal 7 preferably comprises a ring of elastomeric material and is provided with a groove on its inwardly directed surface for receiving the peripheral edge of the baffle plate 6.
  • the baffle plate 6 and the earphone 8 divide the volume within the shell 4 into a closed rear volume la and an open front volume lb.
  • the diaphragm of the earphone is open on the one side to the closed volume la and on the other side to the open volume lb.
  • the compliance of the compliant seal 7 is selected such that the resonant frequency of the baffle plate 6 on the compliant seal 7 is between that of the shell 1 , when being worn as shown in Figure 1, and that of the diaphragm and diaphragm mounted components of the earphone 8, against when the earpiece is being worn as shown in Figure 1.
  • the resonant frequency of the diaphragm and diaphragm mounted components of the earphone 8 is typically 700 Hz to 1000 Hz in use.
  • the compliance of the compliant seal 7 and the mass of the baffle plate 6 are selected to give a preferred resonant frequency for the baffle plate 6 and seal 7 of between, typically, 200 Hz and 300 Hz. It should be noted that the resonant frequency is not limited to this range, and other ranges may be employed, without departing from the scope of the invention. If the resonant frequency of the baffle plate 6 and seal 7 is too low, the baffle plate 6 will move significantly in response to movement of the diaphragm of the earphone 8.
  • a telephone handset which includes a body 10 with a microphone 11 mounted at one end, and an earpiece shell structure 12 at the other end.
  • the earpiece shell structure 12 defines a volume which is divided into a sealed rear chamber 12a and a front chamber 12b by a compliantly mounted baffle plate 6.
  • the front chamber 12b is open to atmosphere through a plurality of holes 13.
  • the compliance of the seal 7 provides extra acoustic isolation between the diaphragm of the earphone 8 and the shell 4, 12. It is anticipated that this extra acoustic isolation may be achieved in other ways, for example, by use of a flexibly resilient baffle plate sealed directly to the shell 4, 12. Such an embodiment may be practiced within the scope of this invention.
  • an active ear defender can be constructed to give a total attenuation level of 40 to 45 dB from 200 Hz upwards which represents a significant and surprising improvement over the prior art.

Abstract

An earpiece (1) for active noise cancellation is disclosed. A headset embodying the earpiece, and a handset of a conventional telephone embodying the earpiece are also disclosed. The earpiece includes an outer shell (4); a baffle (6) including a compliant seal (7) for extending across the inside of the shell to define a closed volume (1a) therein; and a sound producer (8) such as a speaker mounted on the baffle for directing anti-noise sound towards the user's ear.

Description

EARPIECE FOR ACTIVE NOISE CANCELLING HEADSET
FIELD OF THE INVENTION
The present invention relates to an earpiece for active noise cancellation, and a headset or telephone handset including such an earpiece.
BACKGROUND OF THE INVENTION
A conventional ear defender provides a high degree of high frequency passive attenuation by means of a combination of the mass of the shell and the compliance of the air enclosed by the shell. These elements form a second order low pass filter such that the higher the mass and the larger the enclosed volume, the higher the degree of attenuation.
In a conventional active ear defender, as described in European Patent Application No. 333411, an earphone is mounted on an annular baffle, rigidly fixed inside the shell. The baffle is sealed to the inner surface of the shell and the earphone is mounted across the opening in the baffle to define a sealed volume in the shell. At high frequencies, the air volume behind the earphone is isolated from that in front of the earphone and is thereby prevented from contributing to the attenuation at the ear. Thus, a normal active ear defender gives poorer high frequency attenuation than a passive ear defender of the same size and weight. Typically, a passive ear defender might give 40 to 45 dB attenuation above 1 kHz, whereas an active ear defender gives only 30 dB. Furthermore, there is a tendency for active ear defenders to enhance higher frequency noise.
SUMMARY OF THE INVENTION It is an object of the present invention to provide an improved earpiece for active noise cancellation headset and a headset for active ear defense.
It is another object of the present invention to provide an improved earpiece for an active noise cancellation telephone handset and a telephone handset for active ear defense. According to a first aspect of the present invention, there is provided an earpiece for an active noise cancellation, comprising: a shell covering or holding to a user's ear; a baffle extending across the inside of the shell to define a closed volume therein; and a sound producer mounted on the baffle for directing anti-noise sound towards the user's ear. The baffle is sufficiently compliant to enhance passive attenuation of sound having a frequency above 200 Hz.
Active noise cancellation for the range of frequencies above 200 Hz where the enhancement of passive attenuation needs to occur will depend on various factors including the bandwidth of the active noise cancelling system employing the earpiece, and the detailed structure of the earpiece. Thus, for instance, it is envisaged that the enhancement may not occur below 300 Hz. Preferably, the baffle comprises a stiff baffle plate and a compliant seal for connecting the baffle plate to the shell. Alternatively, the baffle plate itself may be formed of suitably flexible resilient material.
Preferably, the sound producer includes a moving sound producing diaphragm structure, and the resonant frequency of the baffle is below that of the diaphragm structure in use.
One or more microphones may be associated with the earpiece as required by the active noise control system employed. The shell may form part of a telephone handset. According to a second aspect of the present invention, there is provided a headset for active ear defense, comprising: first and second earpieces for respective ears of the user, and a headband coupling earpieces, wherein each earpiece comprises a shell for holding to one of the user's ears; baffle means extending across the shell to define a closed volume therein; and a sound producer mounted on the baffle for directing anti- noise sound towards the user's ear, wherein the baffle is sufficiently compliant to enhance passive attenuation of a sound having a frequency above 200 Hz. According to a third aspect of the present invention, there is provided an active noise cancelling system, comprising an earpiece, a shell for covering or holding to a user's ear, a baffle mans extending across the shell to define a closed volume therein, a sound producer mounted on the baffle, and a microphone, wherein the baffle means is sufficiently compliant to enhance passive attenuation of a sound having frequency above 200 Hz, and an electronic controller for producing signals to drive the sound producer to produce cancelling sound in response to the output of the microphone.
Such a system is applicable to a single earpiece handset of a conventional telephone or other headset. A system having two earpieces for a headset is also disclosed.
BRIEF DESCRIPTION OF THE DRAWINGS
Figure 1 shows a headset according to the present invention; Figure 2 shows a cross-sectional view of an earpiece according to the present invention; and
Figure 3 shows a telephone handset according to the present invention.
DESCRIPTION OF AN EMBODIMENT An embodiment of the present invention will now be described, by way of example, with reference to the accompanying drawings.
Referring to Figure 1, an active ear defender is shown comprising a pair of earpieces 1 coupled by a headband 2. An electronic control unit 3 monitors the sound in the earpieces and sends drive signals to a sound producer (not shown) mounted in each earpiece to produce cancelling sound. The cancelling sound destructively interferes with incident noise to achieve quieting in the earpieces 1. A suitable electronic control unit 3 is disclosed in PCT Application No. GB92/01399.
Referring to Figure 2, the earpiece 1 is shown comprising a cup-shaped shell 4, having a radially inwardly extending lip 4a, an annular cushion 5 supported on the lip 4a, a rigid annular baffle plate 6, supported by an annular compliant seal 7 affixed to the inner surface of the shell 4, a small speaker or earphone 8 (hereinafter referred to as an earphone) mounted on the baffle plate 6 across the central opening therein and a microphone 9 located on the ear side of the baffle plate 6. The compliant seal 7 preferably comprises a ring of elastomeric material and is provided with a groove on its inwardly directed surface for receiving the peripheral edge of the baffle plate 6. The baffle plate 6 and the earphone 8 divide the volume within the shell 4 into a closed rear volume la and an open front volume lb. The diaphragm of the earphone is open on the one side to the closed volume la and on the other side to the open volume lb. The compliance of the compliant seal 7 is selected such that the resonant frequency of the baffle plate 6 on the compliant seal 7 is between that of the shell 1 , when being worn as shown in Figure 1, and that of the diaphragm and diaphragm mounted components of the earphone 8, against when the earpiece is being worn as shown in Figure 1.
The resonant frequency of the diaphragm and diaphragm mounted components of the earphone 8 is typically 700 Hz to 1000 Hz in use. In the present invention, the compliance of the compliant seal 7 and the mass of the baffle plate 6 are selected to give a preferred resonant frequency for the baffle plate 6 and seal 7 of between, typically, 200 Hz and 300 Hz. It should be noted that the resonant frequency is not limited to this range, and other ranges may be employed, without departing from the scope of the invention. If the resonant frequency of the baffle plate 6 and seal 7 is too low, the baffle plate 6 will move significantly in response to movement of the diaphragm of the earphone 8. This creates an acoustic short which limits the sound pressure that can be achieved in the open volume lb of the earpiece 1. Referring to Figure 3, wherein like numbers indicate the same structure as in Figure 2, a telephone handset is shown, which includes a body 10 with a microphone 11 mounted at one end, and an earpiece shell structure 12 at the other end. The earpiece shell structure 12 defines a volume which is divided into a sealed rear chamber 12a and a front chamber 12b by a compliantly mounted baffle plate 6. The front chamber 12b is open to atmosphere through a plurality of holes 13. Although the invention is described with reference to a handset, the invention may be embodied in other telephone headsets, such as "hands free" headsets.
Referring to both Figs. 2 and 3, it should be noted the compliance of the seal 7 provides extra acoustic isolation between the diaphragm of the earphone 8 and the shell 4, 12. It is anticipated that this extra acoustic isolation may be achieved in other ways, for example, by use of a flexibly resilient baffle plate sealed directly to the shell 4, 12. Such an embodiment may be practiced within the scope of this invention.
As can be appreciated with a system as described above, an active ear defender can be constructed to give a total attenuation level of 40 to 45 dB from 200 Hz upwards which represents a significant and surprising improvement over the prior art.
Although the invention has been described in detail with particular reference to a preferred embodiment thereof, it should be understood that the invention is capable of other and different embodiments, and its details are capable of modifications in various obvious respects. As is readily apparent to those skilled in the art, variations and modifications can be affected while remaining within the spirit and scope of the invention. Accordingly, the foregoing disclosure, description, and figures are for illustrative purposes only, and do not in any way limit the invention, which is defined only by the claims.

Claims

1. An active noise cancellation earpiece assembly, comprising: a shell having a concave interior; a baffle extending across said concave interior of said shell to define a closed volume therein; and a sound producer mounted on said baffle for generating anti- noise, wherein said baffle is sufficiently compliant to enhance passive attenuation of sound having a frequency above a selected threshold.
2. An earpiece assembly according to claim 1, wherein said baffle includes: a rigid baffle plate; and a resilient seal for connecting said baffle plate to said shell.
3. An earpiece assembly according to claim 1, wherein said sound producer includes a moving sound producing diaphragm structure, and wherein the resonant frequency of said baffle is below that of said diaphragm structure.
4. An earpiece assembly according to claim 1, including a microphone positioned in the propagation path of said anti- noise generated by said sound producer.
5. A headset for active ear defense, comprising: first and second earpieces for respective ears of a user, wherein each of said earpieces comprises: a shell; a baffle extending across said shell to define a closed volume therein, wherein said baffle is sufficiently compliant to enhance passive attenuation of sound at frequencies above 200 Hz; and a sound producer mounted on said baffle for generating anti-noise within said shell; and a headband coupling said earpieces.
6. A headset according to claim 5, wherein said baffle comprises: a rigid baffle plate; and a resilient seal coupling said baffle plate to said shell.
7. A headset according to claim 5, wherein the sound producer includes a moving sound producing diaphragm structure, and wherein the resonant frequency of said baffle is below that of said diaphragm structure.
8. A headset according to claim 5, wherein each earpiece includes a microphone positioned in the propagation path of said anti-noise generated by said sound producer.
9. An active noise cancellation earpiece, comprising: a shell; a baffle extending across said shell to define a closed volume therein, wherein said baffle is sufficiently compliant to enhance passive attenuation of sound having a frequency above 200 Hz; a sound producer mounted on said baffle; a microphone mounted within said shell; and an electronic controller for producing signals to drive said sound producer to produce anti-noise in response to sound detected by said microphone.
10. An earpiece according to claim 9, wherein said baffle comprises: a rigid baffle plate; and a resilient seal coupling said baffle plate to said shell.
11. An earpiece according to claim 9, wherein said sound producer includes a moving sound producing diaphragm structure, and wherein the resonant frequency of said baffle is below that of said diaphragm structure.
12. An active noise cancelling system, comprising: a shell; a baffle extending across said shell to define a closed volume therein, wherein said baffle is sufficiently compliant to enhance passive attenuation of sound at frequencies above 200 Hz; a sound producer mounted on said baffle; a microphone mounted in the propagation path of sound produced by said sound producer; and an electronic controller for producing signals to drive said sound producer to produce anti-noise in response to sound detected by said microphone.
13. A system according to claim 12, wherein said baffle comprises: a rigid baffle plate; and a compliant seal coupling said baffle plate to said shell.
14. A system according to claim 12, wherein said sound producer includes a moving sound producing diaphragm structure, and wherein the resonant frequency of said baffle is below that of said diaphragm structure.
15. The earpiece assembly of claim 1, wherein said earpiece further comprises a telephone handset attached to said shell.
16. The earpiece assembly of claim 9, wherein said earpiece further comprises a telephone handset attached to said shell.
17. The earpiece assembly of claim 12, wherein said earpiece further comprises a telephone handset attached to said shell.
PCT/US1994/000849 1993-01-29 1994-01-28 Earpiece for active noise cancelling headset WO1994017513A1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AU61274/94A AU6127494A (en) 1993-01-29 1994-01-28 Earpiece for active noise cancelling headset

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US1142793A 1993-01-29 1993-01-29
US08/011,427 1993-01-29

Publications (1)

Publication Number Publication Date
WO1994017513A1 true WO1994017513A1 (en) 1994-08-04

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2008084035A1 (en) * 2007-01-08 2008-07-17 Sennheiser Electronic Gmbh & Co. Kg Headset with active noise compensation
EP3185241A1 (en) * 2015-12-23 2017-06-28 Harman Becker Automotive Systems GmbH Externally coupled loudspeaker system

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1989000746A1 (en) * 1987-07-20 1989-01-26 Plessey Overseas Limited Improvements relating to noise reduction systems
SU1697798A1 (en) * 1987-12-02 1991-12-15 Киевский Политехнический Институт Им.50-Летия Великой Октябрьской Социалистической Революции Anti-noise ear-phones
GB2265790A (en) * 1992-04-02 1993-10-06 Polural Limited Earphone apparatus with active noise reduction

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1989000746A1 (en) * 1987-07-20 1989-01-26 Plessey Overseas Limited Improvements relating to noise reduction systems
SU1697798A1 (en) * 1987-12-02 1991-12-15 Киевский Политехнический Институт Им.50-Летия Великой Октябрьской Социалистической Революции Anti-noise ear-phones
GB2265790A (en) * 1992-04-02 1993-10-06 Polural Limited Earphone apparatus with active noise reduction

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
EDGAR SHAW ET AL.: "Acoustics of circumaural earphones", JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA, vol. 34, no. 9, September 1962 (1962-09-01), NEW YORK US, pages 1233 - 1246 *
SOVIET PATENTS ABSTRACTS Week 9240, Derwent World Patents Index; AN 92-329384, "Anti-noise earphones" *

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2008084035A1 (en) * 2007-01-08 2008-07-17 Sennheiser Electronic Gmbh & Co. Kg Headset with active noise compensation
EP3185241A1 (en) * 2015-12-23 2017-06-28 Harman Becker Automotive Systems GmbH Externally coupled loudspeaker system
US10235985B2 (en) 2015-12-23 2019-03-19 Harman Becker Automotive Systems Gmbh Externally coupled loudspeaker system for a vehicle

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