AU746673B2 - Panel-form loudspeakers - Google Patents
Panel-form loudspeakers Download PDFInfo
- Publication number
- AU746673B2 AU746673B2 AU74390/98A AU7439098A AU746673B2 AU 746673 B2 AU746673 B2 AU 746673B2 AU 74390/98 A AU74390/98 A AU 74390/98A AU 7439098 A AU7439098 A AU 7439098A AU 746673 B2 AU746673 B2 AU 746673B2
- Authority
- AU
- Australia
- Prior art keywords
- panel
- smaller
- larger
- panels
- attached
- 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.)
- Ceased
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
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
- H04R7/00—Diaphragms for electromechanical transducers; Cones
- H04R7/02—Diaphragms for electromechanical transducers; Cones characterised by the construction
- H04R7/04—Plane diaphragms
- H04R7/045—Plane diaphragms using the distributed mode principle, i.e. whereby the acoustic radiation is emanated from uniformly distributed free bending wave vibration induced in a stiff panel and not from pistonic motion
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
- H04R9/00—Transducers of moving-coil, moving-strip, or moving-wire type
- H04R9/06—Loudspeakers
Landscapes
- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Acoustics & Sound (AREA)
- Signal Processing (AREA)
- Multimedia (AREA)
- Audible-Bandwidth Dynamoelectric Transducers Other Than Pickups (AREA)
- Diaphragms For Electromechanical Transducers (AREA)
- Details Of Audible-Bandwidth Transducers (AREA)
- Obtaining Desirable Characteristics In Audible-Bandwidth Transducers (AREA)
Description
WO 98/52381 PCT/GB98/01362 TITLE: PANEL-FORM LOUDSPEAKERS
DESCRIPTION
FIELD OF THE INVENTION The invention relates to panel-form loudspeakers, and more particularly, but not exclusively, to panel-form loudspeakers of the kind described in our International Application W097/09842 and known as distributed mode loudspeakers.
BACKGROUND ART In theory and given the availability of the right materials, a distributed mode loudspeaker can cover the full audio range in a single panel. Since the current state of the art in materials technology precludes such a solution, our International Application WO/9709846 envisages small distributed mode loudspeaker panel suspended in a larger distributed mode loudspeaker panel of lower cut-off frequency to produce a wider acoustic bandwidth loudspeaker. This requires at least two exciters of appropriate type and also requires careful design of the mechanical interface between the two panels.
As both panels cover a wide frequency range within their individual capabilities, there will also be a broad frequency range within which the outputs of the two panels may overlap. An electrical cross-over network may therefore be desirable, although it may tend to degrade the sound quality and will add to the manufacturing cost.
An object of the invention is to provide arrangements which alleviate or overcome these difficulties.
GENERAL ASPECTS OF THE INVENTION In one aspect of the invention there is provided a panel-form loudspeaker comprising at least two bending wave resonant distributed mode acoustic panels, including a larger low frequency panel and a smaller higher frequency panel, the larger panel having a lower bending wave stiffness than the smaller, wherein both the larger and smaller panels are excited by a common driver arranged such that bending wave energy is efficiently transferred to both of the larger and smaller panels to excite distributed mode resonance in the larger and smaller panels to provide acoustic output and in that the smaller and larger panels are attached together by a material forming a controlling S 20 compliant coupling whereby differentiation of the high and lower frequency parts of the oo. loudspeaker is achieved.
•go• ooo oo rR\I.IBCC10O91' docemn Desirably, the control of the compliance frequency dependent damping of the coupling allows a preferred cross-over point to be determined mechanically.
Preferably the smaller panels is formed within and attached by the compliant coupling to the larger panel, and a driver being attached to the smaller panel.
Alternatively, a coupler passing through and attached to the larger panel, the smaller panel being mounted on one end of the coupler, and the driver being attached to drive the coupler.
The smaller of said panels is desirably positioned eccentrically with respect to the larger panel.
The driver is desirably positioned eccentrically with respect to the smaller of said panels.
o *go rR \BlRCC102)1) doc-mm WO 98/52381 PCTIGB98/01362 4 BRIEF DESCRIPTION OF THE DRAWINGS The above aspects, features and advantages of the invention will become apparent from the following description of embodiments of the invention now made with reference to the accompanying drawings, in which:- Figure 1 shows at A and B respectively rear face and side views of a first panel-form loudspeaker embodying the invention, Figure 2 is a sectional side view of a second panelform loudspeaker embodying the invention, Figure 3 is a sectional side view of a third panelform loudspeaker embodying the present invention, and Figure 4 is a rear face view of a modified form of the loudspeakers shown in Figure 1 to 3.
BEST MODES FOR CARRYING OUT THE INVENTION Figure 1 shows a smaller distributed mode loudspeaker panel (10) driven by an appropriate driver or exciter preferably an electro-dynamic type for greater bandwidth. The smaller panel (10) is attached face to face to a largerdistributed mode loudspeaker panel (14) of appropriately lower stiffness and of dimensions appropriate to cover the required lower frequency range. By the choice of the right materials and driver design it can be shown that when the smaller panel (10) is driven it will continue to produce its useful bandwidth superimposed on the lower range frequency output resulting from the larger panel (14) giving a much wider bandwidth.
WO 98/52381 PCT/GB98/01362 The smaller distributed mode loudspeaker panel may be attached to the larger one by application of suitable adhesives of low mechanical loss in order to maintain efficient transfer of mechanical energy at low frequencies as well as maintaining good high frequency transmissibility with little loss. Epoxy resin adhesives are suitable for this purpose. The position of attachment of the smaller panel (10) to the larger panel (14) will be chosen in accordance with the distributed mode principle as explained in our International Application WO/97/09842, as will the position of attachment of the exciter (12) to the smaller panel Figure 2 illustrates another type of panel-form loudspeaker embodying the invention in which a larger, low frequency optimised distributed mode panel (20) is modified by having a smaller, high frequency optimised panel (22) formed in the region of a driver The common driving point of the driver (24) means that both parts or regions of the panel are excited. The smaller, high frequency part or region of the panel is provided by extra stiffening of the local skin region (26) for example by adding bonded carbon fibre, glass fibre or similar high strength material. Alternatively, by adding new higher stiffness skin sections in that region.
Depending upon the wave propagation properties of the larger panel (20) a natural balance of power division with frequency may be obtained. Additionally a suitable compliant boundary (28) is incorporated to WO 98/52381 PCT/GB98/01362 6 differentiate between the high and lower frequency parts of the panel. Control of the compliance frequency dependent damping of the resilient coupling allows the ideal or preferred cross-over point to be determined mechanically together with beneficial control of the damping at the boundary between the two parts of the panel.
Figure 3 illustrates yet another type of panel-form loudspeaker embodying the invention. In the arrangement of Figure 3 a smaller, high frequency, panel (30) is adhesively fixed to one end of a light weight tubular coupler Coupler passes through a larger, low frequency panel (34) and is resiliently attached to it as shown at The resilient attachment of the coupler to the larger panel (34) acts as a mechanical low pass filter to further define the balance of energy between the two panels (30 and 34). It can be seen that the end of the coupler (32) spaced from the high frequency panel is fixed to a driver exciter (38).
Yet another arrangement embodying the invention is illustrated in Figure 4 where a single large resonant distributed mode acoustic panel (50) has associated with it a number of smaller panels (52) each having an associated driver The smaller panels (52) may be associated with the larger panel (50) in the ways described with reference to Figures 1 to 3. That is to say the smaller panel (52) may be adhesively attached face to face to the larger panel (50) and have mounted WO 98/52381 PCT/GB98/01362 7 thereon its own driver Alternatively, the smaller panels (52) may comprise a number of sections of the larger panel (50) which have been appropriately stiffened and provided with an individual driver (54) the stiffened sections (52) being coupled to the larger panel in the manner described with reference to Figure 2.
Lastly, the smaller panels (52) may comprise panels carried by couplers each associated with an individual driver in the manner described with reference to Figure 3. It will be appreciated that the smaller panels (52) in the arrangement of Figure 4 need not all be associated with the larger panel (50) in the same was. Some may be associated in the way described with reference to Figure 1 whilst others are associated in the way described with reference to Figures 2 and/or 3.
In the described embodiments the driver is in each case attached or coupled to a smaller panel, it will of course be appreciated that the driver may be attached or coupled to the larger of the panels if desired.
INDUSTRIAL APPLICABILITY The distributed mode loudspeakers described have the benefits of enabling full audio bandwidth from one loudspeaker and reducing the number of drivers required and therefore the cost and complexity of the loudspeakers.
A loudspeaker in accordance with the present invention may be applied to an automobile headliner, with the benefit of a reduced component count, which results WO 98/52381 PCT/GB98/01362 in higher reliability, no need for electrical cross-over components, and reduced manufacturing costs.
Claims (12)
1. A panel-form loudspeaker comprising at least two bending wave resonant distributed mode acoustic panels, including a larger low frequency panel and a smaller higher frequency panel, the larger panel having a lower bending wave stiffness than the smaller, wherein both the larger and smaller panels are excited by a common driver arranged such that bending wave energy is efficiently transferred to both of the larger and smaller panels to excite distributed mode resonance in the larger and smaller panels to provide acoustic output and in that the smaller and larger panels are attached together by a 1o material forming a controlling compliant coupling whereby differentiation of the high and lower frequency parts of the loudspeaker is achieved.
2. A panel-form loudspeaker as claimed in claim 1, wherein control of the compliance frequency dependent damping of the coupling allows a preferred cross-over point to be 15 determined mechanically. S
3. A panel-form loudspeaker as claimed in claim 1 or claim 2, wherein the smaller panel is formed within and attached by the compliant coupling to the larger panel, a driver •being attached to the smaller panel.
A panel-form loudspeaker as claimed in claim 1 or claim 2, comprising a coupler passing through and attached to the larger panel, the smaller panel being mounted on one end of the coupler, and the driver being attached to drive the coupler.
5. A panel-form loudspeaker as claimed in claim 4, wherein the controlling compliance coupling is attached between the coupler and the larger panel and acts as a mechanical low pass filter to further define the balance of energy between the two panels.
6. A panel-form loudspeaker as claimed in claim 4 or claim 5, wherein the driver is attached to the end of the coupler opposite to the end attached to the corresponding smaller panel.
7. A panel-form loudspeaker as claimed in any one of claims 4 to 6, wherein the coupler is tubular in section. [R'ITRCC1o10 Q doc'mrn
8. A panel-form loudspeaker is claimed in any preceding claim, wherein the smaller panel is positioned eccentrically with respect to the larger panel.
9. A panel-form loudspeaker as claimed in any preceding claim, wherein said driver is positioned eccentrically with respect to the smaller of said panels.
A panel-form loudspeaker as claimed in any preceding claim, comprising a single large resonant distributed mode acoustic panel having associated therewith a number of smaller panels each having an associated driver.
11. A panel-form loudspeaker according to any one of claims 1 to 9, wherein there are exactly two panels.
12. A panel-form loudspeaker substantially as described herein with reference to the 15 accompanying drawings. •DATED this Thirty-first Day of January, 2002 New Transducers Limited •Patent Attorneys for the Applicant 20 SPRUSON FERGUSON [R:\LIBCC]02919 doc: gmm
Applications Claiming Priority (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GBGB9709959.2A GB9709959D0 (en) | 1997-05-15 | 1997-05-15 | Panel-form loudspeakers |
GB9709959 | 1997-05-15 | ||
PCT/GB1998/001362 WO1998052381A2 (en) | 1997-05-15 | 1998-05-13 | Panel-form loudspeakers |
Publications (2)
Publication Number | Publication Date |
---|---|
AU7439098A AU7439098A (en) | 1998-12-08 |
AU746673B2 true AU746673B2 (en) | 2002-05-02 |
Family
ID=10812418
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
AU74390/98A Ceased AU746673B2 (en) | 1997-05-15 | 1998-05-13 | Panel-form loudspeakers |
Country Status (15)
Country | Link |
---|---|
EP (1) | EP0981928A2 (en) |
JP (1) | JP2002505814A (en) |
KR (1) | KR20010012527A (en) |
CN (1) | CN1255277A (en) |
AR (1) | AR012696A1 (en) |
AU (1) | AU746673B2 (en) |
BR (1) | BR9809642A (en) |
CA (1) | CA2290476A1 (en) |
CO (1) | CO4780081A1 (en) |
GB (1) | GB9709959D0 (en) |
ID (1) | ID20339A (en) |
IL (1) | IL132686A0 (en) |
TW (1) | TW444510B (en) |
WO (1) | WO1998052381A2 (en) |
ZA (1) | ZA983986B (en) |
Families Citing this family (44)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP2178307B1 (en) * | 1998-01-16 | 2013-11-27 | Sony Corporation | Speaker apparatus and electronic apparatus having speaker apparatus enclosed therein |
PL191378B1 (en) | 1998-06-22 | 2006-05-31 | Slab Technology Ltd | Loudspeakers |
GB9826164D0 (en) * | 1998-11-30 | 1999-01-20 | New Transducers Ltd | Acoustic devices |
US6676879B1 (en) | 1999-01-29 | 2004-01-13 | New Transducers Limited | Method of making vehicle interior trim panel with integral loudspeaker |
GB9901895D0 (en) * | 1999-01-29 | 1999-03-17 | New Transducers Ltd | Loudspeakers |
GB9905373D0 (en) * | 1999-03-10 | 1999-05-05 | New Transducers Ltd | Inertial vibration exciters |
GB9915361D0 (en) * | 1999-07-02 | 1999-09-01 | New Transducers Ltd | Acoustic device |
GB0007025D0 (en) * | 2000-03-23 | 2000-05-10 | New Transducers Ltd | Loudspeakers |
US7372968B2 (en) | 2000-11-08 | 2008-05-13 | New Transducers Limited | Loudspeaker driver |
GB0102865D0 (en) | 2001-02-06 | 2001-03-21 | Secr Defence Brit | Panel form loudspeaker |
WO2002082855A2 (en) * | 2001-04-05 | 2002-10-17 | New Transducers Limited | Loudspeaker |
US7245729B2 (en) | 2001-04-05 | 2007-07-17 | New Transducers Limited | Loudspeaker |
US7548854B2 (en) | 2002-01-31 | 2009-06-16 | Awi Licensing Company | Architectural sound enhancement with pre-filtered masking sound |
GB2386026B (en) * | 2002-02-28 | 2005-06-08 | 1 Ltd | Loudspeaker |
US6983819B2 (en) | 2002-04-02 | 2006-01-10 | Awi Licensing Company | Entertainment sound panels |
EP1480489A3 (en) | 2003-05-23 | 2009-07-01 | Alps Electric Co., Ltd. | Exciting device for producing sound |
GB0405475D0 (en) * | 2004-03-11 | 2004-04-21 | New Transducers Ltd | Loudspeakers |
US10158337B2 (en) | 2004-08-10 | 2018-12-18 | Bongiovi Acoustics Llc | System and method for digital signal processing |
US11431312B2 (en) | 2004-08-10 | 2022-08-30 | Bongiovi Acoustics Llc | System and method for digital signal processing |
US8284955B2 (en) | 2006-02-07 | 2012-10-09 | Bongiovi Acoustics Llc | System and method for digital signal processing |
US10848118B2 (en) | 2004-08-10 | 2020-11-24 | Bongiovi Acoustics Llc | System and method for digital signal processing |
JP2006121325A (en) * | 2004-10-20 | 2006-05-11 | Authentic Ltd | Panel-type speaker |
JP2007116422A (en) | 2005-10-20 | 2007-05-10 | Sony Corp | Audio output device and method |
JP2009513051A (en) | 2005-10-21 | 2009-03-26 | エスエフエックス テクノロジーズ リミテッド | Audio device improvements |
US9615189B2 (en) | 2014-08-08 | 2017-04-04 | Bongiovi Acoustics Llc | Artificial ear apparatus and associated methods for generating a head related audio transfer function |
US10069471B2 (en) | 2006-02-07 | 2018-09-04 | Bongiovi Acoustics Llc | System and method for digital signal processing |
US10848867B2 (en) | 2006-02-07 | 2020-11-24 | Bongiovi Acoustics Llc | System and method for digital signal processing |
US11202161B2 (en) | 2006-02-07 | 2021-12-14 | Bongiovi Acoustics Llc | System, method, and apparatus for generating and digitally processing a head related audio transfer function |
US10701505B2 (en) | 2006-02-07 | 2020-06-30 | Bongiovi Acoustics Llc. | System, method, and apparatus for generating and digitally processing a head related audio transfer function |
US9264004B2 (en) | 2013-06-12 | 2016-02-16 | Bongiovi Acoustics Llc | System and method for narrow bandwidth digital signal processing |
US9883318B2 (en) | 2013-06-12 | 2018-01-30 | Bongiovi Acoustics Llc | System and method for stereo field enhancement in two-channel audio systems |
US9906858B2 (en) | 2013-10-22 | 2018-02-27 | Bongiovi Acoustics Llc | System and method for digital signal processing |
US10639000B2 (en) | 2014-04-16 | 2020-05-05 | Bongiovi Acoustics Llc | Device for wide-band auscultation |
US9615813B2 (en) | 2014-04-16 | 2017-04-11 | Bongiovi Acoustics Llc. | Device for wide-band auscultation |
US10820883B2 (en) | 2014-04-16 | 2020-11-03 | Bongiovi Acoustics Llc | Noise reduction assembly for auscultation of a body |
US9564146B2 (en) | 2014-08-01 | 2017-02-07 | Bongiovi Acoustics Llc | System and method for digital signal processing in deep diving environment |
US9638672B2 (en) | 2015-03-06 | 2017-05-02 | Bongiovi Acoustics Llc | System and method for acquiring acoustic information from a resonating body |
GB2539029B (en) * | 2015-06-04 | 2017-06-07 | Amina Tech Ltd | Distributed mode loudspeaker damping oscillations within exciter feet |
JP2018537910A (en) | 2015-11-16 | 2018-12-20 | ボンジョビ アコースティックス リミテッド ライアビリティー カンパニー | Surface acoustic transducer |
US9621994B1 (en) | 2015-11-16 | 2017-04-11 | Bongiovi Acoustics Llc | Surface acoustic transducer |
CA3096877A1 (en) | 2018-04-11 | 2019-10-17 | Bongiovi Acoustics Llc | Audio enhanced hearing protection system |
WO2020028833A1 (en) | 2018-08-02 | 2020-02-06 | Bongiovi Acoustics Llc | System, method, and apparatus for generating and digitally processing a head related audio transfer function |
KR102252696B1 (en) | 2019-10-21 | 2021-05-17 | 삼원액트 주식회사 | Panel with sound reproduction |
KR102215716B1 (en) | 2019-10-21 | 2021-02-18 | 삼원액트 주식회사 | Panel with sound reproduction |
Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4751419A (en) * | 1986-12-10 | 1988-06-14 | Nitto Incorporated | Piezoelectric oscillation assembly including several individual piezoelectric oscillation devices having a common oscillation plate member |
WO1992003024A1 (en) * | 1990-08-04 | 1992-02-20 | The Secretary Of State For Defence In Her Britannic Majesty's Government Of The United Kingdom Of Great Britain And Northern Ireland | Panel-form loudspeaker |
WO1997009846A1 (en) * | 1995-09-02 | 1997-03-13 | New Transducers Limited | Panel-form loudspeakers |
Family Cites Families (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS588000A (en) * | 1981-07-06 | 1983-01-17 | Murata Mfg Co Ltd | Piezoelectric speaker |
-
1997
- 1997-05-15 GB GBGB9709959.2A patent/GB9709959D0/en active Pending
-
1998
- 1998-05-12 ZA ZA983986A patent/ZA983986B/en unknown
- 1998-05-13 IL IL13268698A patent/IL132686A0/en unknown
- 1998-05-13 BR BR9809642-7A patent/BR9809642A/en not_active IP Right Cessation
- 1998-05-13 EP EP98921596A patent/EP0981928A2/en not_active Withdrawn
- 1998-05-13 CN CN98804923A patent/CN1255277A/en active Pending
- 1998-05-13 WO PCT/GB1998/001362 patent/WO1998052381A2/en not_active Application Discontinuation
- 1998-05-13 AU AU74390/98A patent/AU746673B2/en not_active Ceased
- 1998-05-13 CA CA002290476A patent/CA2290476A1/en not_active Abandoned
- 1998-05-13 JP JP54892498A patent/JP2002505814A/en active Pending
- 1998-05-13 KR KR1019997010482A patent/KR20010012527A/en not_active Application Discontinuation
- 1998-05-14 AR ARP980102243A patent/AR012696A1/en unknown
- 1998-05-15 TW TW087107535A patent/TW444510B/en not_active IP Right Cessation
- 1998-05-15 ID IDP980712A patent/ID20339A/en unknown
- 1998-05-15 CO CO98027492A patent/CO4780081A1/en unknown
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4751419A (en) * | 1986-12-10 | 1988-06-14 | Nitto Incorporated | Piezoelectric oscillation assembly including several individual piezoelectric oscillation devices having a common oscillation plate member |
WO1992003024A1 (en) * | 1990-08-04 | 1992-02-20 | The Secretary Of State For Defence In Her Britannic Majesty's Government Of The United Kingdom Of Great Britain And Northern Ireland | Panel-form loudspeaker |
WO1997009846A1 (en) * | 1995-09-02 | 1997-03-13 | New Transducers Limited | Panel-form loudspeakers |
Also Published As
Publication number | Publication date |
---|---|
KR20010012527A (en) | 2001-02-15 |
EP0981928A2 (en) | 2000-03-01 |
AR012696A1 (en) | 2000-11-08 |
GB9709959D0 (en) | 1997-07-09 |
AU7439098A (en) | 1998-12-08 |
CN1255277A (en) | 2000-05-31 |
JP2002505814A (en) | 2002-02-19 |
TW444510B (en) | 2001-07-01 |
BR9809642A (en) | 2000-07-11 |
ID20339A (en) | 1998-11-26 |
CA2290476A1 (en) | 1998-11-19 |
IL132686A0 (en) | 2001-03-19 |
CO4780081A1 (en) | 1999-05-26 |
ZA983986B (en) | 1999-02-19 |
WO1998052381A3 (en) | 1999-02-18 |
WO1998052381A2 (en) | 1998-11-19 |
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Legal Events
Date | Code | Title | Description |
---|---|---|---|
FGA | Letters patent sealed or granted (standard patent) | ||
MK14 | Patent ceased section 143(a) (annual fees not paid) or expired |