EP0101031A2 - Disposition pour sources sonores évitant des courts-circuits acoustiques dans des haut-parleurs - Google Patents
Disposition pour sources sonores évitant des courts-circuits acoustiques dans des haut-parleurs Download PDFInfo
- Publication number
- EP0101031A2 EP0101031A2 EP83107746A EP83107746A EP0101031A2 EP 0101031 A2 EP0101031 A2 EP 0101031A2 EP 83107746 A EP83107746 A EP 83107746A EP 83107746 A EP83107746 A EP 83107746A EP 0101031 A2 EP0101031 A2 EP 0101031A2
- Authority
- EP
- European Patent Office
- Prior art keywords
- loudspeakers
- air
- sound
- resonance
- membrane
- 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.)
- Withdrawn
Links
Images
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; ELECTRIC HEARING AIDS; 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
- H04R1/2853—Enclosures comprising vibrating or resonating arrangements using an acoustic labyrinth or a transmission line
- H04R1/2857—Enclosures comprising vibrating or resonating arrangements using an acoustic labyrinth or a transmission line for loudspeaker transducers
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; ELECTRIC HEARING AIDS; 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
- H04R1/26—Spatial arrangements of separate transducers responsive to two or more frequency ranges
Definitions
- the invention relates to a device by means of which the mutual cancellation of antiphase sound waves, which are generated by the front and rear membrane surfaces of loudspeakers, can be prevented.
- the device can primarily be used with woofers.
- baffles formed by a rigid, flat plate, the edge of which is outside a circle around the axis of the loudspeaker with the Radius ⁇ / 4, where A is the wavelength of the lowest frequency to be emitted.
- the smallest linear dimension of the baffle is 5.7 to 4.3 meters, so that such baffles cannot be used in practice.
- woofers are operated with loudspeakers that are softly suspended and have a small diaphragm diameter with a large impact. They are also closed in such a way that the acoustic short circuit disappears and the box dimensions are relatively small.
- the lower limit frequency of such sound emitters depends primarily on the housing volume down. Such a housing must be well sealed and manufactured in first-class carpentry work with rigid walls.
- the sound emitter used should have a small diameter in order to achieve a low lower cut-off frequency, as a result of which the load capacity is greatly influenced.
- the characteristic features of an average quality studio control sound source are as follows: lower cut-off frequency 35 Hz, load capacity 40 VA, volume 0.15 m 3 .
- the design of the reflex housing is more complicated than that of a closed housing; however, its efficiency is generally better.
- Known good quality bass radiators are the various embodiments with exponential funnel coupling, which are of particularly good quality - their efficiency is an order of magnitude better than that of radiators with a closed housing - because they not only eliminate the acoustic short circuit, but also because can solve optimal coupling between the speaker and the external sound space.
- Their dimensions are simpler with conical funnels: however, these have a self-resonance that can be remedied by using sound-absorbing material, but this reduces the efficiency.
- Sound emitters with a lower cut-off frequency and a feed path of length A or ⁇ / 4 are also known (A means the wavelength which belongs to the self-resonance frequency of the loudspeaker used).
- A means the wavelength which belongs to the self-resonance frequency of the loudspeaker used.
- these can transform an excessively low load impedance on the loudspeaker membrane into the area of the self-resonance frequency or they cause the increase in the transmission characteristics present here to disappear by canceling signals of the opposite phase.
- the feed path of length A also adds the signals of the two halves of the membrane in phase at half the self-resonance frequency.
- the self-resonances and other internal reflections are also remedied here by installing sound-absorbing material, but this reduces the efficiency.
- This efficiency is lower than that of the baffle, but is better than that of the closed reflex housing.
- the volume of the feed path with the length ⁇ / 4 is approximately the same as that of the reflex housing in the case of the same load capacity; the construction is complicated, but much smaller and simpler than that of the funnel designs.
- the volume of the feed path with a length ⁇ is four times - but is still smaller than that of the funnel designs.
- a very young special solution is described in DE-A-29 34 473.
- a feed line is used here for each frequency to be broadcast, which is referred to as a balanced resona goal works.
- the spectrum image of the electrical signals of the closed generator that is to say the timbre, is shaped with the aid of the resonance. This spotlight can therefore only be used for special electronic instruments, but not for linear transmission.
- a starting point of the invention is that the undesirable resonances of the feed paths%, ⁇ / 4 are not dampened by built-in sound-absorbing materials.
- several loudspeakers of different self-resonance frequencies, and accordingly several feed paths of different lengths, are used simultaneously. Even transmission is ensured by an even distribution of the resonance points.
- the dimensions of the feed paths can thus be independent of the self-resonance frequency of the loudspeakers and the length of the shortest feed path is determined by the requirement to eliminate the acoustic short circuit.
- the lengths of the other feed paths are chosen such that the fundamental resonances of the feed path resonances are at one Area larger than a frequency interval with a ratio of 3: 2 are evenly distributed.
- At least three loudspeakers are provided in a device according to the invention for 5-beam radiators, in particular for emitting deep hairdryers with a characteristic of uniform frequency transmission and good efficiency.
- Each of the loudspeakers is connected to a rigid wall having a closed outer surface in such a way that one end of the air column bounded by the outer surface is closed off by the membrane of the loudspeakers, whereas the other end of the air columns is connected to the outer air space.
- the longitudinal dimensions of the outer surface are chosen such that the shortest air connection between the front and the rear of the respective membrane is not shorter than 1/3 of the wavelength of the sound wave to be emitted with the lowest frequency, the length of the air columns from each other and from half and a quarter of the wavelength of the self-resonance of the connected speakers are different and the inputs of the speakers are connected to a low-impedance generator.
- the embodiments characteristic of the invention are technologically very simple.
- PVC, paper or asbestos cement pipes with the final diameter of the conical membrane of the speakers used are cut to the required lengths (in the case of a cut-off frequency of 30 Hz to 2 to 3 meters) and the speakers are attached at one end by screws . This eliminates the time-consuming and demanding carpentry work.
- the device according to the invention with good efficiency is suitable for transmitting such low frequencies (16 Hz) that cannot be transmitted with the help of baffle, reflex housing and funnel.
- the volume of the device according to the invention larger than the volume of a closed reflex housing, but smaller than that of a baffle or an exponential funnel.
- the invention is suitable for realizing lower limit frequencies as in the known feed paths with a length of ⁇ or A / 4, however their efficiency is better. With the same lower limit frequency and load capacity, their volume is smaller than that of the length A feed path and is generally somewhat larger than that of the length ⁇ / 4 feed path.
- the feed paths of length ⁇ or ⁇ / 4 can also be produced in the described simple form and technology. In this case, the manufacturing costs correspond approximately to the manufacturing costs of the radiator according to the invention
- the manufacturing costs of the other known sound radiators are higher than that of the sound radiator according to the invention (in this comparison, of course, the same lower cut-off frequency and the same load capacity are required).
- An embodiment according to the German publication already mentioned is externally similar to the device according to the invention, since a separate loudspeaker is also used there for each resonance tube (feed path).
- the dimensions of the feed routes according to the invention are different. According to the invention, shorter feed paths are present in any case than in the known embodiment (assuming the same lower cut-off frequency).
- the known embodiment does not require the inputs of the loudspeakers to be connected to a low-impedance generator .
- the bandwidth of the food resonance ie the characteristic of the frequency transmission, may differ from the characteristic of the frequency transmission according to the invention.
- the known construction in general cannot be used for broadband transmission either, but only for amplifying the resonance of the radiation from certain frequencies, for transforming tones with electric organs, configured according to the given timbres.
- the invention consists of a plurality - at least three - speakers 1 having sound emitters, the conical membrane 3 of each speaker 1 is connected to a rigid closed jacket-shaped or tubular wall 2 such that the membrane 3 of the speaker 1 one end of the the circumferential surface of the air column 4 is completed, while the other end of the air column 4 is connected to the outer air space.
- the lateral surface and the air column 4 enclosed therein are referred to here as the "feed path”.
- the German publication mentioned above refers to this construction as a "resonance pipe”.
- the front and back of the loudspeaker membrane are separated from each other by the jacket surfaces. Their lengths should be chosen so that the shortest, through the air, connecting the two sides of the membrane Link (see the dashed line in Fig. 1) should not be shorter than a third of the wavelength of the cut-off frequency to be transmitted for any loudspeaker, and that the lengths of the air columns differ from each other.
- the loudspeakers are to be driven with a generator of low impedance.
- the air columns can be bent straight or arbitrarily, turned, bent with their sections adjoining one another and the like (see FIG. 2).
- the lower limit frequency of the sound system is decisively determined by the shortest feed path (it is less influenced by the longer feed paths). If the two ends of the feed paths are close to each other, the shortest air connection between the two sides of the membrane is reduced compared to such a connection with a straight feed path. Through these feed paths, however, the volume velocities become in phase at their own self-resonance frequency, so that a higher degree of efficiency is achieved. It is obvious that the longest feed paths should be designed in this way in a sound emitter system.
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)
- Circuit For Audible Band Transducer (AREA)
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| HU251482 | 1982-08-05 | ||
| HU251482A HU186101B (en) | 1982-08-05 | 1982-08-05 | Sound radiator without effect of acoustic short circuit of the loadspeakers |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| EP0101031A2 true EP0101031A2 (fr) | 1984-02-22 |
| EP0101031A3 EP0101031A3 (fr) | 1986-04-09 |
Family
ID=10959778
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| EP83107746A Withdrawn EP0101031A3 (fr) | 1982-08-05 | 1983-08-05 | Disposition pour sources sonores évitant des courts-circuits acoustiques dans des haut-parleurs |
Country Status (2)
| Country | Link |
|---|---|
| EP (1) | EP0101031A3 (fr) |
| HU (1) | HU186101B (fr) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5170435A (en) * | 1990-06-28 | 1992-12-08 | Bose Corporation | Waveguide electroacoustical transducing |
| EP0624045A1 (fr) * | 1993-05-06 | 1994-11-09 | Bose Corporation | Amortisseur pour guide d'ondes acoustique, sélectif en fréquence |
| DE19601217C1 (de) * | 1996-01-15 | 1997-07-24 | Mark Iv Audio Deutschland Gmbh | Baßreflexbox |
| WO2008056258A3 (fr) * | 2006-11-10 | 2008-07-03 | Pss Belgium Nv | Système de haut-parleur |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US1912454A (en) * | 1932-03-03 | 1933-06-06 | William H Hutter | Acoustic apparatus |
| US3993162A (en) * | 1975-06-20 | 1976-11-23 | Kenneth Juuti | Acoustic speaker system |
-
1982
- 1982-08-05 HU HU251482A patent/HU186101B/hu not_active IP Right Cessation
-
1983
- 1983-08-05 EP EP83107746A patent/EP0101031A3/fr not_active Withdrawn
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5170435A (en) * | 1990-06-28 | 1992-12-08 | Bose Corporation | Waveguide electroacoustical transducing |
| EP0624045A1 (fr) * | 1993-05-06 | 1994-11-09 | Bose Corporation | Amortisseur pour guide d'ondes acoustique, sélectif en fréquence |
| US6278789B1 (en) | 1993-05-06 | 2001-08-21 | Bose Corporation | Frequency selective acoustic waveguide damping |
| DE19601217C1 (de) * | 1996-01-15 | 1997-07-24 | Mark Iv Audio Deutschland Gmbh | Baßreflexbox |
| WO2008056258A3 (fr) * | 2006-11-10 | 2008-07-03 | Pss Belgium Nv | Système de haut-parleur |
Also Published As
| Publication number | Publication date |
|---|---|
| HU186101B (en) | 1985-06-28 |
| EP0101031A3 (fr) | 1986-04-09 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| DE3883624T2 (de) | Lautsprechersystem. | |
| DE4446690B4 (de) | Lautsprecheranordnung | |
| DE3404655A1 (de) | Vorrichtung zur uebertragung von druckwellen | |
| EP0657630B1 (fr) | Arrangement d'atténuation active de son | |
| DE3410134A1 (de) | Lautsprecher-system mit einem mit mehreren schalloeffnungen versehenen gehaeuse | |
| DE3637910C2 (fr) | ||
| DE3317518A1 (de) | Lautsprecherbox mit integriertem akustischem bandpassfilter | |
| DE2536439A1 (de) | Lautsprechersystem | |
| DE69225328T2 (de) | Lautsprecher mit einem gehäuse in form eines hexagonalen-prismas | |
| DE3818366A1 (de) | Lautsprecheranlage | |
| DE624049C (de) | In ein Gehaeuse eingebauter Flaechenlautsprecher | |
| DE1159028B (de) | Lautsprechersystem fuer stereophonische Wiedergabe | |
| DE2509369A1 (de) | Offenes lautsprecher-gehaeuse | |
| DE2801227B2 (de) | Lautsprecherbox mit Hornresonator | |
| DE2236306B2 (de) | Schallstrahler | |
| EP0101031A2 (fr) | Disposition pour sources sonores évitant des courts-circuits acoustiques dans des haut-parleurs | |
| DE3144545A1 (de) | Lautsprechersystem | |
| DE19601217C1 (de) | Baßreflexbox | |
| EP0692922B1 (fr) | Enceinte acoustique pour haut-parleur basse-fréquence | |
| DE588363C (de) | Lautwiedergabegeraet mit Exponentialtrichter | |
| DE4109758A1 (de) | Lautsprecherbox | |
| DE899679C (de) | Schallwandleranordnung mit gemeinsamem Wandlersystem | |
| DE1044890B (de) | Lautsprechergehaeuse | |
| DE102005030712B4 (de) | Lautsprecherbox | |
| DE4307655C2 (de) | Lautsprecheranordnung |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PUAI | Public reference made under article 153(3) epc to a published international application that has entered the european phase |
Free format text: ORIGINAL CODE: 0009012 |
|
| AK | Designated contracting states |
Designated state(s): AT DE FR IT |
|
| PUAL | Search report despatched |
Free format text: ORIGINAL CODE: 0009013 |
|
| AK | Designated contracting states |
Kind code of ref document: A3 Designated state(s): AT DE FR IT |
|
| STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: THE APPLICATION IS DEEMED TO BE WITHDRAWN |
|
| 18D | Application deemed to be withdrawn |
Effective date: 19860303 |
|
| RIN1 | Information on inventor provided before grant (corrected) |
Inventor name: ALBERT, TAMAS Inventor name: ALBERT, PETER, DIPL. Inventor name: OTOLTICS, VIDOR |