US3780824A - Acoustic loading system - Google Patents
Acoustic loading system Download PDFInfo
- Publication number
- US3780824A US3780824A US00280403A US3780824DA US3780824A US 3780824 A US3780824 A US 3780824A US 00280403 A US00280403 A US 00280403A US 3780824D A US3780824D A US 3780824DA US 3780824 A US3780824 A US 3780824A
- Authority
- US
- United States
- Prior art keywords
- diaphragm
- radiator
- passive
- mass
- enclosure
- 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 - Lifetime
Links
- 239000000725 suspension Substances 0.000 claims abstract description 11
- 230000009467 reduction Effects 0.000 claims description 5
- 238000006073 displacement reaction Methods 0.000 description 17
- 230000004044 response Effects 0.000 description 6
- 230000000737 periodic effect Effects 0.000 description 3
- 230000005855 radiation Effects 0.000 description 2
- 241000725028 Kuwayama Species 0.000 description 1
- 241000489861 Maximus Species 0.000 description 1
- 230000001133 acceleration Effects 0.000 description 1
- 230000003213 activating effect Effects 0.000 description 1
- 238000004026 adhesive bonding Methods 0.000 description 1
- QVZZPLDJERFENQ-NKTUOASPSA-N bassianolide Chemical compound CC(C)C[C@@H]1N(C)C(=O)[C@@H](C(C)C)OC(=O)[C@H](CC(C)C)N(C)C(=O)[C@@H](C(C)C)OC(=O)[C@H](CC(C)C)N(C)C(=O)[C@@H](C(C)C)OC(=O)[C@H](CC(C)C)N(C)C(=O)[C@@H](C(C)C)OC1=O QVZZPLDJERFENQ-NKTUOASPSA-N 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 238000012505 colouration Methods 0.000 description 1
- 230000006835 compression Effects 0.000 description 1
- 238000007906 compression Methods 0.000 description 1
- 230000003111 delayed effect Effects 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 230000003993 interaction Effects 0.000 description 1
- 238000001228 spectrum Methods 0.000 description 1
- 230000002463 transducing effect Effects 0.000 description 1
- 230000001052 transient effect Effects 0.000 description 1
- 239000002023 wood Substances 0.000 description 1
Images
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
- H04R1/20—Arrangements for obtaining desired frequency or directional characteristics
- H04R1/22—Arrangements for obtaining desired frequency or directional characteristics for obtaining desired frequency characteristic only
- H04R1/28—Transducer mountings or enclosures modified by provision of mechanical or acoustic impedances, e.g. resonator, damping means
- H04R1/2807—Enclosures comprising vibrating or resonating arrangements
- H04R1/283—Enclosures comprising vibrating or resonating arrangements using a passive diaphragm
- H04R1/2834—Enclosures comprising vibrating or resonating arrangements using a passive diaphragm for loudspeaker transducers
Definitions
- FIG 3A FREQUENCY V HZ.
- the present invention relates to passive, radiators and more particularly to a massive passive radiator having an additional predetermined mass to improvethe low frequency reproduction capability of an active radiator used in conjunction therewith.
- Passive radiators heretofore known are utilized to simulate the mechanical characteristics of the low frequency active radiator to smooth out its response.
- the passive radiators are also constructed with minimum mass. At low frequencies I6 -50 Hz) within the audible range the output of the passive radiator will shift completely out of phase with the active radiator resulting in distortion and loss of gain.
- loudspeaker system which will provide a more closely linear response from BASS to MEDIUM by means of radical reduction of resonance peaks; improvement in bass transient response; reduction in unnatural colouration in bass frequencies and a reduction in cabinet resonant output (due to pressure build-up in the cabinet); direct the pressure build-up energy to be spent in useful sound radiation instead of producing spurious box resonances; and provide better bass handling power.
- the present invention provides a loudspeaker system comprising an enclosure having at least one active radiator and at least one passive radiator mounted in respective openings in the enclosure.
- the passive radiator has a diaphragm supported by a highly compliant suspension.
- a mass is coaxially distributed and attached to the passive diaphragm. The mass is chosen so that the movement of the passive radiator will be substantially in phase with the movement of the active radiator within the frequency range of between approximately 20 Hz -100 Hz. This mass is sufficient to reduce the natural resonance frequency of the loudspeaker system to a frequency substantially lower than its natural resonance frequency without the added mass attached to the passive diaphragm.
- the reduction in the natural resonance frequency is approximately one octave.
- FIGS. 1A and 1B are front and rear views respectively, of a passive radiator constructed in accordance with the present invention
- FIGS. 1C and ID are sectional side views of a passive massive diaphragm showing the suspensions
- FIG. 2 is a schematic cross-sectional view of a suggested enclosed loudspeaker system having an active radiator and a passive massive radiator;
- FIG. 3A is an actual frequency response curve of a system embodying the present invention.
- FIG. 3B is an actual power input curve of a loudspeaker embodying the present invention.
- FIGS. 4A and 4B are actual frequency response and power input curves of the same loudspeaker system as in FIGS. 3A and 3B but with the passive radiator having no additional mass, and
- FIGS. 5 shows response curves representing the phase relation of the displacement values of the active radiator, the pressure values of the enclosure, the velocity values of the massive passive radiator and the displacement values of the massive passive radiator DESCRIPTION OF PREFERRED EMBODIMENTS
- massive passive radiator is intended to mean a diaphragm mounted or suspended in an acoustic enclosure so that it will be as free as possible to move inward or outward inthe enclosure port much like the diaphragm of an ordinary loudspeaker, but loaded with a suitable mass.
- the diaphragm is passive because it contains no motor or motive power source of its own and is actuated only by the pressure impulses generated in the enclosure by the back of an active radiator associated with it, while it is delayed or retarded in its motion by the reaction of its mass which offers resistance to all change in its state either of rest or motion.
- FIGS. 1A to 1D there is shown a massive passive radiator 10 having a diaphragm 20 supported between an exterior suspension 9 and an interior suspension 8.
- the diaphragm 20 is supported within a frame 7.
- a mass herein shown as an element 23 having a predetermined weight is secured to the diaphragm 20 and equally distributed about the center thereof. This mass may be secured to the diaphragm 20 and the suspension 8 by gluing it circumferentially in the diaphragm 20 and suspension 8 as illustrated by the example shown in FIG. 1C, or else could be glued or secured by other suitable means to the back of the diaphragm as illustrated in FIG. 2.
- FIG. 2 there is shown a suggested loudspeaker system incorporating a massive passive radiator 10, according to the present invention.
- the system comprises preferably an air-tight enclosure 11 having two radiator ports 12 and 13 in the front wall 14 thereof.
- An active radiator 15, having a motor 17, is mounted within port 12 and the massive passive radiator 10 in port 13.
- the diaphragm 20 of the massive passive radiator 10 is supported in port 13 preferably by a suitably flexible high-compliance air-tight suspension as shown schematically by numeral 21. It is possible, however, to obtain good results with a stiffer suspension.
- the massive passive radiator 10 may have a short or a long throw excursion.
- the diaphragm of the massive passive radiator 10 can be of any shape, i.e., conic, dome, oval, square or oblong or flat piston type.
- the weight of the mass 23 is determined in acc0rdance with the inner volume of the enclosure 11 being utilized for the particular loudspeaker system and calculated to make the fundamental resonant frequency of the passive diaphragm 20 equal to or lower than the I lowest desired frequency to be reproduced by the active radiator 15.
- This mass can be determined, for example, by adding increments of weight to the passive radiator diaphragm 20 whilst subjecting it to predetermined frequency pressure impulses until the diaphragm is in phase with that predetermined frequency.
- the passive radiator diaphragm 20 ' may have a surface area and excursion approximately equal to or greater than that of the active radiator.
- Simple Harmonic Motion is the name given to the periodic motion, in a straight line, in which the acceleration is in the opposite direction to the displacement (from the rest position), and proportional wit. it is usually the result of interaction between inertia and elasticity, as in the case of a bob or mass suspended from a light spring. It is also found to be the component, along any line, of a uniform circular motion) and any simple harmonic motion is most readily described in terms of the uniform circular motion of which it is a component.
- K.E. Kinetic Energy
- A is amplitude in feet to is angular velocity in radians per second is phase angle of displacement from rest position. Therefore the kinetic energy varies from zero to a maximum corresponding to the phase angle of the displacement. It is zero when the displacement is extreme (90) and (270) and it is maximum when the displacement is zero (0) and (180). Both these maximums and minimums happen twice in each cycle.
- Curve 31 plots the enclosure pressure values on the Y axis.
- Curve 32 plots the velocity values of the massive passive diaphragm on the Y axis, and curve 33 plots the displacement values of the massive passive diaphragm on the Y axis.
- On the X axis are plotted the time or angular values of all the above values.
- the present invention makes use of the out-of-phase energy lost in the back by the active radiator and adds it in phase to the front radiation without loss of waveform. Also a high degree of efficiency is obtained in relatively small enclosures, in proportion to the volume delivered. Still further, the massive passive radiator is non-resonant within its frequency range. A still further important feature of the present invention is that it provides for a system permitting increased power input capabilities within the massive passive radiator frequency range. Further, any type and shape of enclosure can be used and the massive passive radiator can be mounted on any surface of the enclosure. Also, the massive passive radiator has a substantially constant time delay within its frequency range.
- a loudspeaker system comprising an enclosure having at least one active radiator and at least one passive radiator mounted in respective openings in said enclosure, said passive radiator having a diaphragm supported by a highly compliant suspension and a mass coaxially distributed and attached to said passive diaphragm, said mass being chosen so that the movement of the passive radiator will be substantially in phase with the movement of the active radiator within the fre- 6 phase of the back pressure of said active radiator, by said additional mass.
Landscapes
- Health & Medical Sciences (AREA)
- Otolaryngology (AREA)
- Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- Acoustics & Sound (AREA)
- Signal Processing (AREA)
- Obtaining Desirable Characteristics In Audible-Bandwidth Transducers (AREA)
Applications Claiming Priority (4)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US28040372A | 1972-08-14 | 1972-08-14 | |
CA149412A CA938561A (en) | 1972-08-14 | 1972-08-14 | Acoustic loading system |
FR7336494A FR2247867A1 (is) | 1972-08-14 | 1973-10-12 | |
DE19732354614 DE2354614A1 (de) | 1972-08-14 | 1973-10-31 | Passive abstrahlungsmembran |
Publications (1)
Publication Number | Publication Date |
---|---|
US3780824A true US3780824A (en) | 1973-12-25 |
Family
ID=27425608
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US00280403A Expired - Lifetime US3780824A (en) | 1972-08-14 | 1972-08-14 | Acoustic loading system |
Country Status (4)
Country | Link |
---|---|
US (1) | US3780824A (is) |
CA (1) | CA938561A (is) |
DE (1) | DE2354614A1 (is) |
FR (1) | FR2247867A1 (is) |
Cited By (20)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS5136334U (is) * | 1974-09-10 | 1976-03-18 | ||
JPS5177127U (is) * | 1974-12-16 | 1976-06-17 | ||
JPS5245437U (is) * | 1975-09-26 | 1977-03-31 | ||
JPS52136627U (is) * | 1976-04-12 | 1977-10-17 | ||
US4076097A (en) * | 1976-08-04 | 1978-02-28 | Thomas Lowe Clarke | Augmented passive radiator loudspeaker |
US4139075A (en) * | 1976-08-31 | 1979-02-13 | Sansui Electric Co., Ltd. | Loudspeaker device |
US4206830A (en) * | 1977-11-22 | 1980-06-10 | Pioneer Electronic Corporation | Vehicle speaker system provided with a passive radiator |
US5216210A (en) * | 1992-02-27 | 1993-06-01 | Kammer Brent T | Loudspeaker system with passive sound reflective intensifier |
US5731552A (en) * | 1996-05-21 | 1998-03-24 | Tsao; Ye-Ming | Speaker system with sound absorbing diaphragm |
WO2004089036A2 (en) * | 2003-04-04 | 2004-10-14 | Audio Products International Corp. | Outdoor loudspeaker with passive radiator |
US20050157900A1 (en) * | 2004-01-15 | 2005-07-21 | Roman Litovsky | Acoustic passive radiator rocking mode reducing |
US20070127760A1 (en) * | 2004-04-13 | 2007-06-07 | Shuji Saiki | Speaker system |
US20110176701A1 (en) * | 2010-01-16 | 2011-07-21 | Collins William E | Autoaugmented Speaker Port |
US20120279796A1 (en) * | 2011-05-06 | 2012-11-08 | Cheng Uei Precision Industry Co., Ltd. | Passive radiator |
EP2405674A3 (en) * | 2010-07-09 | 2014-08-20 | Siemens Hearing Instruments, Inc. | A hearing aid with occlusion reduction |
US20150304746A1 (en) * | 2014-04-18 | 2015-10-22 | Bose Corporation | Acoustic Element for a Speaker |
US9402126B2 (en) * | 2014-04-17 | 2016-07-26 | Merry Electronics (Shenzhen) Co., Ltd. | Earphone with passive radiator |
US9913012B2 (en) * | 2014-09-12 | 2018-03-06 | Bose Corporation | Acoustic device with curved passive radiators |
WO2022053165A1 (de) * | 2020-09-14 | 2022-03-17 | Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V. | Mems-bauelement, hearable, mems-pumpe, lautsprecher und verfahren zum ansteuern eines mems-bauelements |
US11368787B1 (en) * | 2018-08-17 | 2022-06-21 | Sound Edge LLC | Speaker systems including forward and backward facing passive radiators |
Families Citing this family (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FR2428950A1 (fr) * | 1978-06-15 | 1980-01-11 | Andrieu Michel | Systeme de reproduction sonore resistant aux deflagrations |
DE3326446A1 (de) * | 1983-07-22 | 1985-01-31 | Standard Elektrik Lorenz Ag, 7000 Stuttgart | Verfahren zur herstellung eines passivstrahlers |
DE9306941U1 (de) * | 1993-05-07 | 1993-07-22 | Nokia (Deutschland) GmbH, 7530 Pforzheim | Am Gehäuse oder Chassis eines Gerätes der Unterhaltungselektronik befestigter Lautsprecher |
FR2738442B1 (fr) * | 1995-09-01 | 1997-11-28 | Degreane Ets | Transducteur electrodynamique compense |
Citations (11)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US1787946A (en) * | 1925-05-14 | 1931-01-06 | Victor Talking Machine Co | Means for converting electrical vibrations into sound waves |
US1988250A (en) * | 1934-02-17 | 1935-01-15 | Rca Corp | Loud speaker and method of propagating sound |
US2059929A (en) * | 1935-06-17 | 1936-11-03 | Philco Radio & Television Corp | Sound reproducing apparatus |
US2121008A (en) * | 1936-07-16 | 1938-06-21 | Paul H Bilhuber | Acoustic translating device |
FR1095563A (fr) * | 1953-12-11 | 1955-06-03 | Elipson | Enceinte à résonance compensée pour haut-parleur |
US2757751A (en) * | 1952-04-07 | 1956-08-07 | Ernest A Tavares | Small extended-low-frequency-response loudspeaker enclosure |
US3074504A (en) * | 1961-05-25 | 1963-01-22 | Liberty Mfg Corp | Loud-speaker |
US3115947A (en) * | 1962-02-23 | 1963-12-31 | Warren R Wood | High fidelity sound reproducer |
US3194340A (en) * | 1964-05-15 | 1965-07-13 | Kuwayama Zennosuke | Speaker enclosure system |
US3240289A (en) * | 1963-10-25 | 1966-03-15 | Sony Corp | Sound system |
US3578104A (en) * | 1968-05-20 | 1971-05-11 | Nippon Musical Instruments Mfg | Loudspeaker |
-
1972
- 1972-08-14 CA CA149412A patent/CA938561A/en not_active Expired
- 1972-08-14 US US00280403A patent/US3780824A/en not_active Expired - Lifetime
-
1973
- 1973-10-12 FR FR7336494A patent/FR2247867A1/fr not_active Withdrawn
- 1973-10-31 DE DE19732354614 patent/DE2354614A1/de active Pending
Patent Citations (11)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US1787946A (en) * | 1925-05-14 | 1931-01-06 | Victor Talking Machine Co | Means for converting electrical vibrations into sound waves |
US1988250A (en) * | 1934-02-17 | 1935-01-15 | Rca Corp | Loud speaker and method of propagating sound |
US2059929A (en) * | 1935-06-17 | 1936-11-03 | Philco Radio & Television Corp | Sound reproducing apparatus |
US2121008A (en) * | 1936-07-16 | 1938-06-21 | Paul H Bilhuber | Acoustic translating device |
US2757751A (en) * | 1952-04-07 | 1956-08-07 | Ernest A Tavares | Small extended-low-frequency-response loudspeaker enclosure |
FR1095563A (fr) * | 1953-12-11 | 1955-06-03 | Elipson | Enceinte à résonance compensée pour haut-parleur |
US3074504A (en) * | 1961-05-25 | 1963-01-22 | Liberty Mfg Corp | Loud-speaker |
US3115947A (en) * | 1962-02-23 | 1963-12-31 | Warren R Wood | High fidelity sound reproducer |
US3240289A (en) * | 1963-10-25 | 1966-03-15 | Sony Corp | Sound system |
US3194340A (en) * | 1964-05-15 | 1965-07-13 | Kuwayama Zennosuke | Speaker enclosure system |
US3578104A (en) * | 1968-05-20 | 1971-05-11 | Nippon Musical Instruments Mfg | Loudspeaker |
Cited By (31)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS5136334U (is) * | 1974-09-10 | 1976-03-18 | ||
JPS5177127U (is) * | 1974-12-16 | 1976-06-17 | ||
JPS5245437U (is) * | 1975-09-26 | 1977-03-31 | ||
JPS52136627U (is) * | 1976-04-12 | 1977-10-17 | ||
US4131180A (en) * | 1976-04-12 | 1978-12-26 | Trio Kabushiki Kaisha | Speaker system |
US4076097A (en) * | 1976-08-04 | 1978-02-28 | Thomas Lowe Clarke | Augmented passive radiator loudspeaker |
US4139075A (en) * | 1976-08-31 | 1979-02-13 | Sansui Electric Co., Ltd. | Loudspeaker device |
US4206830A (en) * | 1977-11-22 | 1980-06-10 | Pioneer Electronic Corporation | Vehicle speaker system provided with a passive radiator |
US5216210A (en) * | 1992-02-27 | 1993-06-01 | Kammer Brent T | Loudspeaker system with passive sound reflective intensifier |
US5731552A (en) * | 1996-05-21 | 1998-03-24 | Tsao; Ye-Ming | Speaker system with sound absorbing diaphragm |
WO2004089036A2 (en) * | 2003-04-04 | 2004-10-14 | Audio Products International Corp. | Outdoor loudspeaker with passive radiator |
US20040231911A1 (en) * | 2003-04-04 | 2004-11-25 | Welker Andrew C. | Outdoor loudspeaker with passive radiator |
WO2004089036A3 (en) * | 2003-04-04 | 2005-07-14 | Audio Products Int Corp | Outdoor loudspeaker with passive radiator |
EP1555849A3 (en) * | 2004-01-15 | 2007-03-07 | Bose Corporation | Acoustic passive radiator with rocking-mode reduction |
US20050157900A1 (en) * | 2004-01-15 | 2005-07-21 | Roman Litovsky | Acoustic passive radiator rocking mode reducing |
US7568552B2 (en) | 2004-01-15 | 2009-08-04 | Bose Corporation | Acoustic passive radiator rocking mode reducing |
CN101969594B (zh) * | 2004-01-15 | 2012-07-04 | 伯斯有限公司 | 降低摆动模式的无源声辐射器 |
US20070127760A1 (en) * | 2004-04-13 | 2007-06-07 | Shuji Saiki | Speaker system |
US7477755B2 (en) * | 2004-04-13 | 2009-01-13 | Panasonic Corporation | Speaker system |
US20110176701A1 (en) * | 2010-01-16 | 2011-07-21 | Collins William E | Autoaugmented Speaker Port |
US9794700B2 (en) | 2010-07-09 | 2017-10-17 | Sivantos Inc. | Hearing aid with occlusion reduction |
EP2405674A3 (en) * | 2010-07-09 | 2014-08-20 | Siemens Hearing Instruments, Inc. | A hearing aid with occlusion reduction |
US20120279796A1 (en) * | 2011-05-06 | 2012-11-08 | Cheng Uei Precision Industry Co., Ltd. | Passive radiator |
US9402126B2 (en) * | 2014-04-17 | 2016-07-26 | Merry Electronics (Shenzhen) Co., Ltd. | Earphone with passive radiator |
US20150304746A1 (en) * | 2014-04-18 | 2015-10-22 | Bose Corporation | Acoustic Element for a Speaker |
US9674602B2 (en) * | 2014-04-18 | 2017-06-06 | Bose Corporation | Acoustic element for a speaker |
US20170245049A1 (en) * | 2014-04-18 | 2017-08-24 | Bose Corporation | Acoustic Element for a Speaker |
US10080079B2 (en) * | 2014-04-18 | 2018-09-18 | Bose Corporation | Acoustic element for a speaker |
US9913012B2 (en) * | 2014-09-12 | 2018-03-06 | Bose Corporation | Acoustic device with curved passive radiators |
US11368787B1 (en) * | 2018-08-17 | 2022-06-21 | Sound Edge LLC | Speaker systems including forward and backward facing passive radiators |
WO2022053165A1 (de) * | 2020-09-14 | 2022-03-17 | Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V. | Mems-bauelement, hearable, mems-pumpe, lautsprecher und verfahren zum ansteuern eines mems-bauelements |
Also Published As
Publication number | Publication date |
---|---|
FR2247867A1 (is) | 1975-05-09 |
CA938561A (en) | 1973-12-18 |
DE2354614A1 (de) | 1975-05-15 |
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