EP3278330B1 - Acoustic impedance matching device and loudspeaker provided with such a device - Google Patents
Acoustic impedance matching device and loudspeaker provided with such a device Download PDFInfo
- Publication number
- EP3278330B1 EP3278330B1 EP16712972.5A EP16712972A EP3278330B1 EP 3278330 B1 EP3278330 B1 EP 3278330B1 EP 16712972 A EP16712972 A EP 16712972A EP 3278330 B1 EP3278330 B1 EP 3278330B1
- Authority
- EP
- European Patent Office
- Prior art keywords
- loudspeaker
- chamber
- section
- absorbent material
- horn
- 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.)
- Active
Links
- 239000000463 material Substances 0.000 claims description 50
- 230000002745 absorbent Effects 0.000 claims description 39
- 239000002250 absorbent Substances 0.000 claims description 39
- 239000002657 fibrous material Substances 0.000 claims description 5
- 239000006260 foam Substances 0.000 claims description 5
- 238000010521 absorption reaction Methods 0.000 description 21
- 239000012528 membrane Substances 0.000 description 16
- 230000006978 adaptation Effects 0.000 description 12
- 239000002245 particle Substances 0.000 description 10
- 230000008901 benefit Effects 0.000 description 7
- 230000007423 decrease Effects 0.000 description 7
- 230000033001 locomotion Effects 0.000 description 7
- 230000000750 progressive effect Effects 0.000 description 6
- 230000006835 compression Effects 0.000 description 4
- 238000007906 compression Methods 0.000 description 4
- 230000000694 effects Effects 0.000 description 4
- 230000009467 reduction Effects 0.000 description 3
- 239000004753 textile Substances 0.000 description 3
- 238000013016 damping Methods 0.000 description 2
- 230000006837 decompression Effects 0.000 description 2
- 230000004044 response Effects 0.000 description 2
- 230000005236 sound signal Effects 0.000 description 2
- 240000008415 Lactuca sativa Species 0.000 description 1
- 239000006096 absorbing agent Substances 0.000 description 1
- 239000000470 constituent Substances 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 230000001747 exhibiting effect Effects 0.000 description 1
- 239000000835 fiber Substances 0.000 description 1
- -1 fibrous Substances 0.000 description 1
- 239000003365 glass fiber Substances 0.000 description 1
- 230000003993 interaction Effects 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000003071 parasitic effect Effects 0.000 description 1
- 235000012045 salad Nutrition 0.000 description 1
- 239000000725 suspension Substances 0.000 description 1
- 239000012209 synthetic fiber Substances 0.000 description 1
- 229920002994 synthetic fiber Polymers 0.000 description 1
- 230000009466 transformation Effects 0.000 description 1
- 238000004804 winding Methods 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
- H04R1/2869—Reduction of undesired resonances, i.e. standing waves within enclosure, or of undesired vibrations, i.e. of the enclosure itself
- H04R1/2876—Reduction of undesired resonances, i.e. standing waves within enclosure, or of undesired vibrations, i.e. of the enclosure itself by means of damping material, e.g. as cladding
- H04R1/288—Reduction of undesired resonances, i.e. standing waves within enclosure, or of undesired vibrations, i.e. of the enclosure itself by means of damping material, e.g. as cladding for loudspeaker transducers
-
- 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
- G10K11/002—Devices for damping, suppressing, obstructing or conducting sound in acoustic devices
-
- 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
- H04R1/2861—Enclosures comprising vibrating or resonating arrangements using a back-loaded horn
- H04R1/2865—Enclosures comprising vibrating or resonating arrangements using a back-loaded horn for loudspeaker transducers
-
- 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
- H04R1/30—Combinations of transducers with horns, e.g. with mechanical matching means, i.e. front-loaded horns
Definitions
- the invention relates to the field of acoustics, and more precisely to that of loudspeakers. It relates more specifically to a particular design of an acoustic impedance matching device forming a horn or a horn arranged at the rear of a loudspeaker.
- loudspeakers are electroacoustic devices, which comprise a movable membrane which moves according to the sound signal to be reproduced.
- This mobile membrane generates a pressure wave by setting in motion the mass of air located at the front of the speaker.
- the mass of air which is located at the rear of the diaphragm is also set in motion, thus generating a pressure wave in the rear part of the loudspeaker.
- this rear wave can be reflected towards the rear face of the membrane and thus disturb its vibratory behavior, this can introduce undesirable distortions and a modification of the response in frequency.
- the acoustic absorption obtained within a fibrous, textile or open-cell foam type material is a transformation of acoustic energy into mechanical energy due to the interactions between the molecules of air in motion and the material structure.
- the higher the particle velocity the higher the sound absorption will be. This is the reason why all the previous solutions presented below are based on a reduction in section which results in a higher speed and thus a stronger sound absorption.
- the invention described below proposes a solution which makes it possible to reduce all these phenomena while benefiting from a good level of sound absorption.
- the postulate of the study is based on the fact that a high particle velocity associated with a high absorbent density can be sources of unwanted nonlinear phenomena.
- the invention therefore proposes a progressive absorption solution where the particle velocity decreases as the density of acoustic absorbent increases.
- the invention relates to an acoustic impedance matching device intended to be installed at the rear of a loudspeaker, the device comprising an end of smaller section, intended to be connected to an opening of a loudspeaker. , and an opposite end, the device comprising a chamber at least partially filled with an absorbent material.
- This device is characterized in that the section of the chamber increases between the end of smaller section and the opposite end. Additionally, the density of the absorbent material is also increasing between the end of smaller section and the opposite end.
- the invention consists in using a geometry of the horn opposite to those of the prior art, in order to reduce the particle speed when approaching the end of the horn.
- the amount and density of absorbent material filling the horn increases as it moves away from the loudspeaker, which compensates for the drop in particle velocity in terms of sound absorption.
- the invention consists in controlling the phenomena of sound absorption by the presence of an absorber which is relatively sparse in the immediate vicinity of the loudspeaker, and which becomes denser on approaching the opposite end.
- absorbent materials and in particular fibrous materials, do not have linear acoustic behavior, because of the viscoelastic effect of the fibers.
- the phenomena of friction of the air at the entrance of the horn are reduced and the sound absorption within the horn is therefore more progressive.
- the low density of the absorbent material near the entrance to the pavilion limits sound reflection phenomena.
- the absorption is however effectively ensured then by a higher density of the absorbent material when the acoustic waves progress in the pavilion.
- the widening of the section of the roof makes it possible to reduce the air speed in the zone where the absorbent material is more dense, which thus limits non-linear phenomena while ensuring satisfactory absorption.
- the progressive and simultaneous variation of the absorbent density and of the particle speed allows the invention to limit the reflection phenomena, to benefit from a good level of acoustic absorption and to reduce the non-linearities inherent in the use of materials such as fibrous, textiles and open cell foams.
- the absorbent material can fill the whole of the chamber, or even only part of this chamber.
- the end of the chamber opposite the loudspeaker may be either closed or open.
- the two solutions each have distinct advantages.
- the open solution allows a total absence of reflection of sound waves towards the rear face of the speaker membrane, which improves performance in terms of sound absorption.
- a residual part of the rear wave can be found outside the device, that is to say the listening space, and therefore come to be superimposed on the front wave generated by the speaker, which may in some cases slightly interfere with the acoustic response of the device. This drawback can however be considered marginal with regard to the good sound absorption performance.
- the solution with a closed horn ensures a total absence of the rear wave in the listening space. This can be an advantage in certain configurations, even if the residual part of the back wave which will not be completely absorbed by the device will be reflected against the closed wall and may slightly disturb the vibratory behavior of the loudspeaker membrane.
- the choice of an open or closed solution will therefore depend on other parameters such as the type of loudspeaker concerned (tweeter, medium, woofer), the type of cabinet used, and finally the type of loudspeaker to be produced. .
- the density ratios of the absorbent materials used good results have been observed in practice when the ratio between the maximum and minimum densities of the absorbent material is greater than five. In other words, the density of absorbent material is five times higher at the end of the horn opposite the speaker, compared to the density of the absorbent material at the entrance of the horn.
- the ratio between the maximum and minimum sections of the chamber is advantageously greater than five.
- the horn section widens by a ratio greater than five, between the horn entrance on the speaker side and the opposite end. It should be noted that this increase in the section can be done in one or two directions, so that the overall size of the pavilion is not excessive.
- the absorbent material is generally chosen from among fibrous materials, textiles and open cell foams.
- the chamber has two walls between which the absorbent material is located, the two walls having parallel external faces, and non-parallel internal faces.
- the material of homogeneous density is compressed between the two walls, the outer faces of which are kept parallel, the compression takes place with a progression which generates the desired spatial variation in density.
- the invention also relates to an assembly formed by a loudspeaker and an acoustic absorption device as described above.
- the input of the chamber has a section substantially equal to the rear section of the loudspeaker.
- the characteristic chamber is located in the extension of the opening at the rear of the loudspeaker through which the air set in motion by the membrane is expelled.
- the association of the loudspeaker and the horn may include an additional connection element, connecting the mounting area to the loudspeaker and the chamber itself, so that the difference in section between the area of connection and entry to the chamber is as gradual as possible, and that section rungs which are sources of unwanted reflections are avoided.
- the loudspeaker is incorporated in a box, and in this case, the absorption chamber is mounted on the box.
- the shape of the box and the opening of the chamber are chosen so that the section presented to the acoustic waves is as progressive as possible, and limits parasitic reflection phenomena.
- the invention relates to an acoustic impedance matching device, which is intended to be installed at the rear of a loudspeaker.
- Different configurations can be envisaged, in particular the one illustrated on figure 1 .
- the system shown in figure 1 comprises a loudspeaker 1 which in a simplified manner comprises a membrane 2 movable relative to a salad bowl 6 , via the suspension 7.
- the membrane 2 comprises at its center a cylinder 4 on which is mounted a coil 3 through which it passes. a current representative of the sound signal to be reproduced.
- This winding 3 is bathed in a magnetic field generated by the magnetic motor 5 .
- This magnetic motor has an opening 8 oriented towards the rear, so that the volume 9 located at the rear of the membrane 2 communicates with the outside of the loudspeaker.
- the impedance matching device 10 comprises a horn 11 , the end of which is smaller in section 12 and connected to the opening 8 at the rear of the loudspeaker 1 .
- the section of the opening 12 located on the side of the loudspeaker 1 is smaller than the section at the level of the opposite end 13 .
- the end 13 is open, but it is possible that it is blocked, thus preventing any air from escaping.
- the internal volume of the pavilion 11 is filled with an absorbent material 14 , which may be a fibrous material, for example based on glass fibers or synthetic fibers, or else based on a cell foam. open, or more generally any material consisting of elementary particles capable of moving under the effect of the air circulation generated by the movement of the membrane, and thereby absorbing part of this acoustic energy.
- an absorbent material 14 which may be a fibrous material, for example based on glass fibers or synthetic fibers, or else based on a cell foam. open, or more generally any material consisting of elementary particles capable of moving under the effect of the air circulation generated by the movement of the membrane, and thereby absorbing part of this acoustic energy.
- the filling material 14 occupies only a fraction of the pavilion, now emptying a fraction 16 of the entrance to the pavilion.
- This region 16 thus forms an extension of the rear volume of the loudspeaker, thus limiting the compression, and facilitating the operation of the loudspeaker in the low frequencies.
- the absorbent material can also fill the entire volume of the horn.
- the filling material is placed inside the horn so that its density increases by moving from the end 12 near the loudspeaker, in the direction of the loudspeaker. 'end 13 opposite.
- the damping effect is progressive, and the impact of the absorbent material on the acoustic waves at the start of the horn is less than it is near the opposite end 13 .
- the damping material 14 is a material homogeneous in material, which undergoes progressive compression up to the end 13 of the horn.
- the damping material 14 it is possible in certain variants to use several different materials, therefore exhibiting increasing densities, or more generally gradual absorption capacities, which are arranged in layers superimposed inside the roof.
- the figure 2 illustrates a configuration of the shape of the flag 14 . More precisely, this horn has a rectangular cross section, the width w and the height h of which vary between the end 12 which will be connected to the rear of the loudspeaker and the free end 13 .
- the width and the height can respectively increase and decrease linearly.
- the lateral flanks 21, 22 of the pavilion have a geometry substantially flat, to be compared with the concave geometry, with an outwardly oriented curvature for the side walls 18 , 19 of the roof of the figure 2 , which exhibit an exponential type section growth or the like.
- the pavilion may have a shape such that its side walls have a convexity, that is to say a short curvature oriented inwards, corresponding to a growth of the parameters of logarithmic, parabolic or similar type.
- the progressiveness of the density of the absorbent material inserted inside the horn can be obtained in different ways, and in particular as illustrated in figures 8 and 9 .
- the main faces 30, 31 of the roof are assembled around a layer of uniform thickness of an absorbent material 32 .
- one of the walls, for example the upper wall 30 has a variable thickness, due to the fact that its upper 35 and lower 36 faces are not parallel. More precisely, this thickness increases between the rear face 37 intended to come into contact with the loudspeaker and the face 38 situated opposite the loudspeaker.
- the opposite wall 31 for its part, has a constant thickness, such that its upper face 39 and the lower face 36 of the other wall 30 define a volume of increasing section as it moves away from the loudspeaker.
- the layer 32 is made of a homogeneous material, when the two walls 30 , 31 are brought together, keeping their external faces parallel, the intermediate layer 32 is then compressed to a greater extent in the zone intended to be furthest from the top. speaker.
- the law of variation of the density of the absorbent material can be determined as a function of the desired performance, in accordance with the variation of the section of the horn. This compression can thus be linear, exponential, or conversely logarithmic.
- the acoustic impedance matching device may be connected to the loudspeaker either directly as illustrated in figure 1 , or by means of an additional volume, which as illustrated in figure 10 can be formed by an additional element 50 , of frustoconical shape, of which the inlet section 52 corresponds to the section of the opening 53 located at the rear of the loudspeaker 1, and whose outlet section 54 corresponds to that of the inlet 55 of the chamber 10 .
- an additional element 50 of frustoconical shape, of which the inlet section 52 corresponds to the section of the opening 53 located at the rear of the loudspeaker 1, and whose outlet section 54 corresponds to that of the inlet 55 of the chamber 10 .
- the progressiveness of the section of the chamber is to some extent extended by that of the additional element.
- the shapes and dimensions of this additional element may vary depending on the geometries of the loudspeaker and of the chamber.
- this tubular portion can be variable, depending on the regions connected, and can take on a frustoconical shape or more generally flared in one direction or the other.
- This connecting piece 50 can also have sections of different geometries between its inlet and its outlet. This may in particular be the case where the loudspeaker has a circular decompression opening, and the acoustic adaptation device has a rectangular input section.
- the impedance matching device is connected not directly to the rear opening of the magnetic motor, but to an opening formed in the rear of a box receiving the loudspeaker.
- the loudspeaker 1 is mounted inside a box 60 .
- This box 60 has an opening 62 at which the bowl 56 of the speaker 1 is fixed.
- the box has a wall 64 of substantially constant section, for example rectangular or cylindrical around the loudspeaker.
- the rear wall 66 of the box 60 has an opening 61 of dimensions substantially equal to those of the end 69 of the roof 10 .
- This type of assembly is particularly suitable for loudspeakers whose bowl 56 is perforated, so that the volume of air located at the rear of the membrane 2 communicates with the outside of the loudspeaker not only through the opening 8 for decompression of the magnetic motor, but also through the recesses 57 of the bowl 56 . In this case, the acoustic waves generated by the movement of the membrane and which propagate at the rear of the latter are confined inside the box 60 , and reach the characteristic horn 10 .
- FIG. 12 An alternative embodiment illustrated on figure 12 is composed of a box 70 , the opening 72 of which receives the perforated bowl 56 of speaker 1 .
- the main wall 74 of the box 70 is frustoconical in shape, and ends at the rear, with an opening 71 .
- This opening 71 also has dimensions adapted to the connection of an acoustic adaptation device 10 .
- the frustoconical shape of the box 70 makes it possible to have a progressivity of the section seen by the acoustic waves, with a positive influence on the reflection phenomena.
- the main wall of the box can take other various shapes. It is possible to envisage a shape of substantially constant section, for example cylindrical or parallelepiped, with a characteristic bell whose opening is of suitable geometry, and can in particular have a section similar to that of the box.
- the invention can also be applied to loudspeakers which have a magnetic motor which is not pierced in its center, and in which the air present at the rear of the membrane flows only through through the openings formed in the bowl.
- the impedance matching device has the advantage of ensuring a virtual absence of reflection of sound waves on the rear of the speaker membrane, while at the same time reducing the non-linearities inherent in the usual use of high density absorbent materials. Indeed, the progression of the absorbent effect by the increasing density of the filling material means that the speed of the particles of the air coming into contact with this absorbent material is lower than in the prior art.
- the improvements obtained are reflected in particular by a reduction in distortion and better conservation of the loudspeaker's acoustic performance regardless of the sound level.
Landscapes
- Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- Acoustics & Sound (AREA)
- Health & Medical Sciences (AREA)
- Otolaryngology (AREA)
- Signal Processing (AREA)
- Multimedia (AREA)
- Obtaining Desirable Characteristics In Audible-Bandwidth Transducers (AREA)
- Details Of Audible-Bandwidth Transducers (AREA)
Description
L'invention se rattache au domaine de l'acoustique, et plus précisément à celui des haut-parleurs. Elle vise plus spécifiquement une conception particulière de dispositif d'adaptation d'impédance acoustique formant un cornet ou un pavillon disposé à l'arrière d'un haut-parleur.The invention relates to the field of acoustics, and more precisely to that of loudspeakers. It relates more specifically to a particular design of an acoustic impedance matching device forming a horn or a horn arranged at the rear of a loudspeaker.
De façon générale, les haut-parleurs sont des dispositifs électroacoustiques, qui comportent une membrane mobile qui se déplace en fonction du signal sonore à reproduire. Cette membrane mobile génère une onde de pression en mettant en mouvement la masse d'air situé à l'avant du haut-parleur. Ce faisant, la masse d'air qui est située à l'arrière de la membrane est également mise en mouvement, générant ainsi une onde de pression dans la partie arrière du haut-parleur. Dans certains cas, notamment lors que le haut-parleur est enfermé dans un coffret, cette onde arrière peut être réfléchie vers la face arrière de la membrane et ainsi perturber son comportement vibratoire, cela peut introduire des distorsions indésirables et une modification de la réponse en fréquence. Pour limiter ou annuler ces phénomènes, il est connu de disposer à l'arrière du haut-parleur un dispositif d'adaptation d'impédance acoustique, qui absorbe tout ou partie de l'énergie acoustique générée à l'arrière du haut-parleur.In general, loudspeakers are electroacoustic devices, which comprise a movable membrane which moves according to the sound signal to be reproduced. This mobile membrane generates a pressure wave by setting in motion the mass of air located at the front of the speaker. In doing so, the mass of air which is located at the rear of the diaphragm is also set in motion, thus generating a pressure wave in the rear part of the loudspeaker. In certain cases, in particular when the loudspeaker is enclosed in a cabinet, this rear wave can be reflected towards the rear face of the membrane and thus disturb its vibratory behavior, this can introduce undesirable distortions and a modification of the response in frequency. To limit or cancel out these phenomena, it is known practice to place at the rear of the loudspeaker an acoustic impedance matching device, which absorbs all or part of the acoustic energy generated at the rear of the loudspeaker.
On rappellera ici que l'absorption acoustique obtenue au sein d'un matériau type fibreux, textile, ou mousse à cellules ouvertes, est une transformation de l'énergie acoustique en énergie mécanique due aux interactions entre les molécules d'airs en mouvement et la structure du matériau. Ainsi, plus la vitesse particulaire est élevée, plus l'absorption acoustique sera élevée. C'est la raison pour laquelle toutes les solutions antérieures présentées ci-dessous sont basées sur une réduction de section qui entraine une vitesse plus élevée et ainsi une plus forte absorption acoustique.It will be recalled here that the acoustic absorption obtained within a fibrous, textile or open-cell foam type material is a transformation of acoustic energy into mechanical energy due to the interactions between the molecules of air in motion and the material structure. Thus, the higher the particle velocity, the higher the sound absorption will be. This is the reason why all the previous solutions presented below are based on a reduction in section which results in a higher speed and thus a stronger sound absorption.
Différentes solutions ont déjà été proposées, comme celle décrite dans le document
Une solution équivalente a été décrite dans le document
Une variante a été décrite dans le document
L'ensemble de ces solutions présentent donc des cornets dont la section est globalement décroissante en s'éloignant du haut-parleur, ceci afin de bénéficier des avantages d'une vitesse particulaire élevée dans les matériaux absorbants.All of these solutions therefore have cones, the section of which decreases overall as it moves away from the loudspeaker, in order to benefit from the advantages of a high particle speed in absorbent materials.
Ces solutions permettent en effet d'obtenir ainsi des niveaux d'absorption acoustique très élevés, mais ceci parfois au détriment de la linéarité. En effet, l'utilisation simultanée d'une grande vitesse particulaire et d'une haute densité d'absorbant entraine des phénomènes non linéaires liés au comportement viscoélastique des matériaux utilisés. On rappellera ici aussi que l'utilisation d'un matériau absorbant de densité élevée favorise l'absorption acoustique, mais favorise aussi la réflexion d'ondes sonores résiduelles vers la face arrière de la membrane,These solutions in fact make it possible to thus obtain very high sound absorption levels, but this sometimes to the detriment of linearity. Indeed, the simultaneous use of a high particle speed and a high absorbent density leads to nonlinear phenomena linked to the viscoelastic behavior of the materials used. It will also be recalled here that the use of an absorbent material of high density promotes sound absorption, but also promotes the reflection of residual sound waves towards the rear face of the membrane,
L'invention décrite ci-dessous propose une solution qui permet de réduire tous ces phénomènes tout en bénéficiant d'un bon niveau d'absorption acoustique.The invention described below proposes a solution which makes it possible to reduce all these phenomena while benefiting from a good level of sound absorption.
Comme décrit précédemment, le postulat de l'étude est basé sur le fait qu'une vitesse particulaire élevée associée à une densité d'absorbant élevée peuvent être sources de phénomènes non linéaires non désirés. L'invention propose donc une solution d'absorption progressive où la vitesse particulaire décroit au fur et à mesure que la densité d'absorbent acoustique augmente.As described above, the postulate of the study is based on the fact that a high particle velocity associated with a high absorbent density can be sources of unwanted nonlinear phenomena. The invention therefore proposes a progressive absorption solution where the particle velocity decreases as the density of acoustic absorbent increases.
L'invention concerne un dispositif d'adaptation d'impédance acoustique destiné à être implanté à l'arrière d'un haut-parleur, le dispositif comportant une extrémité de moindre section, destinée à être reliée à une ouverture d'un haut-parleur, et une extrémité opposée, le dispositif comportant une chambre au moins partiellement remplie d'un matériau absorbant.The invention relates to an acoustic impedance matching device intended to be installed at the rear of a loudspeaker, the device comprising an end of smaller section, intended to be connected to an opening of a loudspeaker. , and an opposite end, the device comprising a chamber at least partially filled with an absorbent material.
Ce dispositif se caractérise en ce que la section de la chambre est croissante entre l'extrémité de moindre section et l'extrémité opposée. Complémentairement, la densité du matériau absorbant est également croissante entre l'extrémité de moindre section et l'extrémité opposée.This device is characterized in that the section of the chamber increases between the end of smaller section and the opposite end. Additionally, the density of the absorbent material is also increasing between the end of smaller section and the opposite end.
Autrement dit, l'invention consiste à utiliser une géométrie de pavillon opposée à celles de l'art antérieur, ceci pour réduire la vitesse particulaire en se rapprochant de l'extrémité du pavillon. Toutefois, grâce à l'invention, la quantité et la densité de matière absorbante remplissant le pavillon augmentent en s'éloignant du haut-parleur, ce qui compense la baisse de vitesse particulaire en termes d'absorption acoustique.In other words, the invention consists in using a geometry of the horn opposite to those of the prior art, in order to reduce the particle speed when approaching the end of the horn. However, thanks to the invention, the amount and density of absorbent material filling the horn increases as it moves away from the loudspeaker, which compensates for the drop in particle velocity in terms of sound absorption.
En d'autres termes, l'invention consiste à contrôler les phénomènes d'absorption acoustique par la présence d'un absorbant qui est relativement peu dense à proximité immédiate du haut-parleur, et qui se densifie en se rapprochant de l'extrémité opposée. Le Demandeur a constaté que les matériaux absorbants, et en particulier les matériaux fibreux, n'ont pas un comportement acoustique linéaire, à cause de l'effet viscoélastique des fibres.In other words, the invention consists in controlling the phenomena of sound absorption by the presence of an absorber which is relatively sparse in the immediate vicinity of the loudspeaker, and which becomes denser on approaching the opposite end. . The Applicant has observed that absorbent materials, and in particular fibrous materials, do not have linear acoustic behavior, because of the viscoelastic effect of the fibers.
Grâce à la configuration de l'invention, et en particulier la faible densité du matériau absorbant à proximité du haut-parleur, les phénomènes de frottements de l'air à l'entrée du pavillon sont réduits et l'absorption acoustique au sein du pavillon est donc plus progressive. La faible densité du matériau absorbant à proximité de l'entrée du pavillon limite les phénomènes de réflexion sonore. L'absorption est toutefois efficacement assurée ensuite par une plus forte densité du matériau absorbant lorsque les ondes acoustiques progressent dans le pavillon. L'élargissement de la section du pavillon permet de diminuer la vitesse d'air dans la zone où le matériau absorbant est plus dense, ce qui limite ainsi les phénomènes non linéaires tout en assurant une absorption satisfaisante.Thanks to the configuration of the invention, and in particular the low density of the absorbent material near the loudspeaker, the phenomena of friction of the air at the entrance of the horn are reduced and the sound absorption within the horn is therefore more progressive. The low density of the absorbent material near the entrance to the pavilion limits sound reflection phenomena. The absorption is however effectively ensured then by a higher density of the absorbent material when the acoustic waves progress in the pavilion. The widening of the section of the roof makes it possible to reduce the air speed in the zone where the absorbent material is more dense, which thus limits non-linear phenomena while ensuring satisfactory absorption.
En résumé, la variation progressive et simultanée de la densité d'absorbant et de la vitesse particulaire permet à l'invention de limiter les phénomènes de réflexion, de bénéficier d'un bon niveau d'absorption acoustique et de réduire les non linéarités inhérentes à l'utilisation de matériaux tels que fibreux, textiles et mousses à cellules ouvertes.In summary, the progressive and simultaneous variation of the absorbent density and of the particle speed allows the invention to limit the reflection phenomena, to benefit from a good level of acoustic absorption and to reduce the non-linearities inherent in the use of materials such as fibrous, textiles and open cell foams.
On constate ainsi une meilleure conservation des performances acoustiques du haut-parleur quel que soit le niveau sonore.There is thus a better conservation of the acoustic performance of the loudspeaker whatever the sound level.
Différentes configurations, géométries et conceptions peuvent être envisagées.Different configurations, geometries and designs can be considered.
En fonction du type de haut-parleur utilisé et des performances à atteindre en termes d'absorption, le matériau absorbant peut emplir l'intégralité de la chambre, ou bien encore une partie seulement de cette chambre.Depending on the type of loudspeaker used and the performance to be achieved in terms of absorption, the absorbent material can fill the whole of the chamber, or even only part of this chamber.
Selon une autre caractéristique de l'invention, l'extrémité de la chambre opposée au haut-parleur peut-être soit obturée soit ouverte. Les deux solutions présentent chacune des avantages distincts. La solution ouverte permet une totale absence de réflexion des ondes sonores vers la face arrière de la membrane du haut-parleur, ce qui améliore les performances en termes d'absorption acoustique. On notera toutefois qu'une partie résiduelle de l'onde arrière peut se retrouver à l'extérieur du dispositif, c'est-à-dire l'espace d'écoute, et venir donc se superposer à l'onde avant générée par le haut-parleur, ce qui peut dans certains cas, perturber légèrement la réponse acoustique du dispositif. Cet inconvénient peut toutefois être considéré comme marginal au regard des bonnes performances d'absorption acoustique.According to another characteristic of the invention, the end of the chamber opposite the loudspeaker may be either closed or open. The two solutions each have distinct advantages. The open solution allows a total absence of reflection of sound waves towards the rear face of the speaker membrane, which improves performance in terms of sound absorption. Note, however, that a residual part of the rear wave can be found outside the device, that is to say the listening space, and therefore come to be superimposed on the front wave generated by the speaker, which may in some cases slightly interfere with the acoustic response of the device. This drawback can however be considered marginal with regard to the good sound absorption performance.
La solution avec un pavillon fermé assure une totale absence de l'onde arrière dans l'espace d'écoute. Ceci peut constituer un avantage dans certaines configurations, même si la partie résiduelle de l'onde arrière qui ne sera pas totalement absorbée par le dispositif viendra se réfléchir contre la paroi fermée et pourra perturber légèrement le comportement vibratoire de la membrane du haut-parleur. Le choix d'une solution ouverte ou fermée se fera donc en fonction d'autres paramètres comme le type de haut-parleur concerné (tweeter, médium, woofer), le type de coffret utilisé, et enfin le type d'enceinte acoustique à réaliser.The solution with a closed horn ensures a total absence of the rear wave in the listening space. This can be an advantage in certain configurations, even if the residual part of the back wave which will not be completely absorbed by the device will be reflected against the closed wall and may slightly disturb the vibratory behavior of the loudspeaker membrane. The choice of an open or closed solution will therefore depend on other parameters such as the type of loudspeaker concerned (tweeter, medium, woofer), the type of cabinet used, and finally the type of loudspeaker to be produced. .
Concernant les rapports de densité des matériaux absorbants utilisés, on a observé en pratique de bons résultats lorsque le rapport entre les densités maximale et minimale du matériau absorbant est supérieur à cinq. En d'autres termes, la densité en matériau absorbant est cinq fois plus élevée au niveau de l'extrémité du pavillon opposée au haut-parleur, par rapport à la densité du matériau absorbant à l'entrée du pavillon.Regarding the density ratios of the absorbent materials used, good results have been observed in practice when the ratio between the maximum and minimum densities of the absorbent material is greater than five. In other words, the density of absorbent material is five times higher at the end of the horn opposite the speaker, compared to the density of the absorbent material at the entrance of the horn.
De même manière, le rapport entre les sections maximale et minimale de la chambre est avantageusement supérieur à cinq. En d'autres termes, la section du pavillon s'élargit d'un rapport supérieur à cinq, entre l'entrée du pavillon du côté du haut-parleur et l'extrémité opposée. Il est à noter que cette augmentation de la section peut se faire dans une ou deux directions, de sorte que l'encombrement global du pavillon n'est pas excessif.Likewise, the ratio between the maximum and minimum sections of the chamber is advantageously greater than five. In other words, the horn section widens by a ratio greater than five, between the horn entrance on the speaker side and the opposite end. It should be noted that this increase in the section can be done in one or two directions, so that the overall size of the pavilion is not excessive.
En pratique, le matériau absorbant est généralement choisi parmi les matériaux fibreux, les textiles et les mousses à cellules ouvertes.In practice, the absorbent material is generally chosen from among fibrous materials, textiles and open cell foams.
Il est possible d'utiliser un matériau qui a été fabriqué avec la progressivité de densité souhaitée. Il est également possible d'utiliser un matériau de densité homogène dont la progressivité est obtenue lors de la fabrication de la chambre elle-même. Dans ce cas, la chambre comporte deux parois entre lesquelles est situé le matériau absorbant, les deux parois présentant des faces externes parallèles, et des faces internes non parallèles. Lorsque le matériau de densité homogène est comprimé entre les deux parois dont les faces externes sont maintenues parallèles, la compression se fait avec une progression qui engendre la variation spatiale de densité souhaitée.It is possible to use a material which has been manufactured with the desired progressiveness in density. It is also possible to use a material of homogeneous density, the progressiveness of which is obtained during the manufacture of the chamber itself. In this case, the chamber has two walls between which the absorbent material is located, the two walls having parallel external faces, and non-parallel internal faces. When the material of homogeneous density is compressed between the two walls, the outer faces of which are kept parallel, the compression takes place with a progression which generates the desired spatial variation in density.
L'invention concerne également un ensemble formé d'un haut-parleur et d'un dispositif d'absorption acoustique tel que décrit plus haut. En pratique, pour assurer une variation d'impédance continue, on privilégiera les solutions dans laquelle l'entrée de la chambre présente une section sensiblement égale à la section arrière du haut-parleur. En d'autres termes, la chambre caractéristique se trouve dans le prolongement de l'ouverture de l'arrière du haut-parleur par lequel est expulsé l'air mis en mouvement par la membrane.The invention also relates to an assembly formed by a loudspeaker and an acoustic absorption device as described above. In practice, to ensure a continuous variation of impedance, we will favor solutions in which the input of the chamber has a section substantially equal to the rear section of the loudspeaker. In other words, the characteristic chamber is located in the extension of the opening at the rear of the loudspeaker through which the air set in motion by the membrane is expelled.
En pratique, l'association du haut-parleur et du pavillon peut inclure un élément additionnel de raccordement, reliant la zone de montage au haut-parleur et la chambre à proprement parler, de manière à ce que la différence de section entre la zone de raccordement et l'entrée de la chambre soit la plus progressive possible, et que l'on évite les échelons de section qui sont des sources de réflexions intempestives.In practice, the association of the loudspeaker and the horn may include an additional connection element, connecting the mounting area to the loudspeaker and the chamber itself, so that the difference in section between the area of connection and entry to the chamber is as gradual as possible, and that section rungs which are sources of unwanted reflections are avoided.
Il est également possible que le haut-parleur soit incorporé dans un caisson, et dans ce cas, la chambre d'absorption est montée sur le caisson. De préférence, la forme du caisson et l'ouverture de la chambre sont choisies pour que la section présentée aux ondes acoustiques soit la plus progressive possible, et limite les phénomènes de réflexion parasites.It is also possible that the loudspeaker is incorporated in a box, and in this case, the absorption chamber is mounted on the box. Preferably, the shape of the box and the opening of the chamber are chosen so that the section presented to the acoustic waves is as progressive as possible, and limits parasitic reflection phenomena.
La manière de réaliser l'invention, ainsi que les avantages qui en découlent ressortiront bien de la description des modes de réalisation qui suit, à l'appui des figures annexées dans lesquelles :
- la
figure 1 est une vue en coupe longitudinale simplifiée d'un moteur de haut-parleur associé à un dispositif d'adaptation acoustique conforme à l'invention. - la
figure 2 est une vue en perspective sommaire du dispositif d'adaptation acoustique de lafigure 1 - les
figures 3, 4 sont des vues en coupe transversale du dispositif de laet 5figure 2 , respectivement selon les plans de coupe III-III', IV-IV', V-V' ; - les
figures 6 et 7 sont des vues en perspective sommaire de variantes de réalisation du dispositif d'adaptation acoustique - les
figures 8 et 9 sont des vues en perspective sommaire montrant les différents éléments constitutifs d'une variante de réalisation du dispositif d'adaptation acoustique, respectivement avant et après assemblage ; - les
figures 10, 11 et 12 sont des vues en coupe longitudinale de trois variantes de réalisation d'un haut-parleur équipé d'un dispositif d'adaptation acoustique conforme à l'invention.
- the
figure 1 is a simplified longitudinal sectional view of a loudspeaker motor associated with an acoustic adaptation device according to the invention. - the
figure 2 is a summary perspective view of the acoustic adaptation device of thefigure 1 - the
figures 3, 4 and 5 are cross-sectional views of the device of thefigure 2 , respectively according to the section planes III-III ', IV-IV', VV '; - the
figures 6 and 7 are summary perspective views of alternative embodiments of the acoustic adaptation device - the
figures 8 and 9 are summary perspective views showing the different constituent elements of an alternative embodiment of the acoustic adaptation device, respectively before and after assembly; - the
figures 10, 11 and 12 are views in longitudinal section of three variant embodiments of a loudspeaker equipped with an acoustic adaptation device according to the invention.
Comme déjà évoqué, l'invention concerne un dispositif d'adaptation d'impédance acoustique, qui est destiné à être implanté à l'arrière d'un haut-parleur. Différentes configurations peuvent être envisagées, en particulier celle illustrée à la
Le système illustré à la
Au niveau de cette ouverture 8, on note la présence du dispositif d'adaptation d'impédance 10. Ce dispositif comporte un pavillon 11 dont l'extrémité de moindre section 12 et reliée à l'ouverture 8 de l'arrière du haut-parleur 1. Conformément à l'invention, la section de l'ouverture 12 située du côté du haut-parleur 1 est inférieure à la section au niveau de l'extrémité opposée 13. Dans la forme illustrée, l'extrémité 13 est ouverte, mais il est possible qu'elle soit obturée, empêchant ainsi toute sortie d'air.At this
Conformément à l'invention, le volume intérieur du pavillon 11 est rempli d'un matériau absorbant 14, pouvant être un matériau fibreux, à base par exemple de fibres de verre de fibres synthétiques, ou bien encore à base d'une mousse à cellules ouvertes, ou de manière plus générale tout matériau constitué de particules élémentaires susceptibles de se déplacer sous l'effet de la circulation de l'air engendrée par le mouvement de la membrane, et ce faisant d'absorber une partie de cette énergie acoustique.According to the invention, the internal volume of the
Dans la forme illustrée, le matériau de remplissage 14 n'occupe qu'une fraction du pavillon, maintenant vide une fraction 16 de l'entrée du pavillon. Cette région 16 forme ainsi un prolongement du volume arrière du haut-parleur, limitant ainsi la compression, et facilitant le fonctionnement du haut-parleur dans les basses fréquences. Dans d'autres modes de réalisation, le matériau absorbant peut aussi remplir l'intégralité du volume du pavillon.In the form illustrated, the filling
Selon une caractéristique de l'invention, le matériau de remplissage est mis en place à l'intérieur du pavillon de telle sorte que sa densité s'accroît en se dirigeant depuis l'extrémité 12 à proximité du haut-parleur, en direction de l'extrémité 13 opposée. De la sorte, l'effet d'amortissement est progressif, et l'impact du matériau absorbant sur les ondes acoustiques au début du pavillon est moindre qu'il ne l'est à proximité de l'extrémité opposée 13.According to one characteristic of the invention, the filling material is placed inside the horn so that its density increases by moving from the
De manière préférée, le matériau amortissant 14 est un matériau homogène en matière, qui subit une compression progressive jusqu'à l'extrémité 13 du pavillon. Toutefois, il est envisageable dans certaines variantes d'utiliser plusieurs matériaux différents, présentant donc des densités croissantes, ou plus généralement des capacités d'absorption graduelle, qui sont agencés par couche superposées à l'intérieur du pavillon.Preferably, the damping
La
On note comme illustré aux
Différentes lois de croissance peuvent être envisagées pour les différents paramètres permettant d'obtenir la progression souhaitée de la section. Ainsi, comme illustré à la
A l'inverse, comme illustré à la
La progressivité de la densité du matériau absorbant inséré à l'intérieur du pavillon peut être obtenue de différentes manières, et en particulier tel qu'illustré aux
La paroi opposée 31 présente quant à elle une épaisseur constante, de telle sorte que sa face supérieure 39 et la face inférieure 36 de l'autre paroi 30, définissent un volume de section croissante en s'éloignant du haut-parleur. La couche 32 est réalisée en un matériau homogène, lorsque les deux parois 30,31 sont rapprochées, en maintenant leurs faces externes parallèles, la couche intermédiaire 32 est alors comprimée de manière plus importante dans la zone destinée à être la plus éloignée du haut-parleur.The
La loi de variation de la densité du matériau absorbant peut être déterminée en fonction des performances souhaitées, en accord avec la variation de la section du pavillon. Cette compression peut ainsi être linéaire, exponentielle, ou à l'inverse logarithmique.The law of variation of the density of the absorbent material can be determined as a function of the desired performance, in accordance with the variation of the section of the horn. This compression can thus be linear, exponential, or conversely logarithmic.
Selon un autre aspect de l'invention, le dispositif d'adaptation d'impédance acoustique peut-être reliée au haut-parleur soit directement comme illustré à la
Bien entendu, la forme de cette portion tubulaire peut être variable, en fonction des régions raccordées, et peut épouser une forme tronconique ou plus généralement évasée dans un sens ou dans l'autre. Cette pièce de raccordement 50 peut aussi présenter des sections de géométries différentes entre son entrée et sa sortie. Il peut en particulier s'agir du cas où le haut-parleur présente une ouverture de décompression circulaire, et le dispositif d'adaptation acoustique possède une section d'entrée rectangulaire.Of course, the shape of this tubular portion can be variable, depending on the regions connected, and can take on a frustoconical shape or more generally flared in one direction or the other. This connecting
Il est également possible que le dispositif d'adaptation d'impédance soit relié non pas directement sur l'ouverture arrière du moteur magnétique, mais à une ouverture formée dans l'arrière d'un caisson recevant le haut-parleur.It is also possible that the impedance matching device is connected not directly to the rear opening of the magnetic motor, but to an opening formed in the rear of a box receiving the loudspeaker.
Ainsi, comme illustré à la
Une variante de réalisation illustrée à la
Il est évident que l'invention peut également s'appliquer aux haut-parleurs qui présentent un moteur magnétique qui n'est pas percé en son centre, et dans lequel l'air présent à l'arrière de la membrane s'écoule uniquement à travers les ouvertures formées dans le saladier.It is obvious that the invention can also be applied to loudspeakers which have a magnetic motor which is not pierced in its center, and in which the air present at the rear of the membrane flows only through through the openings formed in the bowl.
Il ressort de ce qui précède que le dispositif d'adaptation d'impédance conforme à l'invention présente l'avantage d'assurer une quasi-absence de réflexion des ondes sonores sur l'arrière de la membrane du haut-parleur ceci tout en réduisant les non linéarités inhérentes à l'utilisation habituelle de matériaux absorbants de forte densité. En effet, la progression de l'effet absorbant par la densité croissante du matériau de remplissage fait que la vitesse des particules de l'air entrant en contact avec ce matériau absorbant est moindre que dans l'art antérieur.It emerges from the foregoing that the impedance matching device according to the invention has the advantage of ensuring a virtual absence of reflection of sound waves on the rear of the speaker membrane, while at the same time reducing the non-linearities inherent in the usual use of high density absorbent materials. Indeed, the progression of the absorbent effect by the increasing density of the filling material means that the speed of the particles of the air coming into contact with this absorbent material is lower than in the prior art.
Les améliorations obtenues se traduisent notamment par une réduction de la distorsion et une meilleure conservation des performances acoustiques du haut-parleur quel que soit le niveau sonore.The improvements obtained are reflected in particular by a reduction in distortion and better conservation of the loudspeaker's acoustic performance regardless of the sound level.
Claims (11)
- Acoustic impedance matching device (10) intended to be implanted behind a loudspeaker (1), said device comprising an end of small section, intended to be connected to an opening of a loudspeaker (1), and an opposite end (13), said device comprising a chamber (11) at least partially filled with an absorbent material (14), characterized in that:- the cross-section of the chamber (11) increases between the end of small section and the opposite end (13);- the density of the absorbent material (14) increases between the end of small section and the opposite end (13).
- Device according to claim 1, characterized in that the absorbent material fills the entire chamber (11).
- Device according to claim 1, characterized in that the absorbent material (14) fills only a part of the chamber.
- Device according to claim 1, characterized in that the end of the chamber opposite the loudspeaker is closed.
- Device according to claim 1, characterized in that the opposite end (13) is open.
- Device according to claim 1, characterized in that the ratio between the maximum and minimum densities of the absorbent material (14) is greater than five.
- Device according to claim 1, characterized in that the ratio between the maximum and minimum sections of the chamber (11) is greater than five.
- Device according to claim 1, characterized in that the absorbent material (14) is selected from the group consisting of fibrous materials and open cell foams.
- Device according to claim 1, characterized in that it has two walls between which the absorbent material is located, the two walls having parallel external faces and non-parallel internal faces.
- Assembly formed by a speaker and a device according to claims 1 to 9, characterized in that it has a connection element (50) connecting the loudspeaker (1) and the chamber (11).
- Assembly according to claim 10, characterized in that the entrance to the chamber (11) has a cross-section substantially equal to the cross-section behind the loudspeaker.
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
FR1552852A FR3034564B1 (en) | 2015-04-02 | 2015-04-02 | ACOUSTIC IMPEDANCE ADAPTING DEVICE AND SPEAKER EQUIPPED WITH SUCH A DEVICE |
PCT/FR2016/050615 WO2016156697A1 (en) | 2015-04-02 | 2016-03-18 | Acoustic impedance matching device and loudspeaker provided with such a device |
Publications (2)
Publication Number | Publication Date |
---|---|
EP3278330A1 EP3278330A1 (en) | 2018-02-07 |
EP3278330B1 true EP3278330B1 (en) | 2021-03-03 |
Family
ID=53200186
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP16712972.5A Active EP3278330B1 (en) | 2015-04-02 | 2016-03-18 | Acoustic impedance matching device and loudspeaker provided with such a device |
Country Status (4)
Country | Link |
---|---|
US (1) | US10306353B2 (en) |
EP (1) | EP3278330B1 (en) |
FR (1) | FR3034564B1 (en) |
WO (1) | WO2016156697A1 (en) |
Families Citing this family (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB2590656A (en) * | 2019-12-23 | 2021-07-07 | Gp Acoustics International Ltd | Loudspeakers |
Family Cites Families (13)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2293181A (en) | 1940-07-17 | 1942-08-18 | Int Standard Electric Corp | Sound absorbing apparatus |
JPS5151926A (en) * | 1974-11-01 | 1976-05-07 | Sansui Electric Co | Supiikasochi |
US4139076A (en) * | 1978-01-30 | 1979-02-13 | Hruby Jr John O | Loudspeaker enclosure with enhanched bass response |
DE3117693A1 (en) * | 1981-04-29 | 1982-11-18 | Mario Brescia Cesati | Method for manufacturing loudspeakers with angle radiation and loudspeaker manufactured in accordance with this method |
US4410064A (en) * | 1982-01-27 | 1983-10-18 | Taddeo Anthony R | Bass response speaker housing and method of tuning same |
GB8503389D0 (en) * | 1985-02-09 | 1985-03-13 | B & W Loudspeakers | Loudspeaker enclosures |
FR2704675B1 (en) * | 1993-04-27 | 1995-07-07 | Lecompte Roland | Device for attenuating the energy of acoustic waves emitted by a sound source in at least one determined direction. |
US5828759A (en) * | 1995-11-30 | 1998-10-27 | Siemens Electric Limited | System and method for reducing engine noise |
GB2324928B (en) | 1997-05-02 | 2001-09-12 | B & W Loudspeakers | Loudspeaker systems |
US6700984B1 (en) | 1999-12-07 | 2004-03-02 | California Institute Of Technology | Non-linearly tapering transmission line speakers |
JP2007262282A (en) * | 2006-03-29 | 2007-10-11 | Toshiba Corp | Acoustic material, method for producing the same and method for regenerating acoustic material |
EP2040483B1 (en) * | 2007-09-21 | 2013-02-27 | Laurence George Dickie | Ported loudspeaker enclosure with tapered waveguide absorber |
EP2737721A4 (en) * | 2011-07-25 | 2015-06-03 | G Licensing Llc Dr | Ultra-low profile loudspeakers |
-
2015
- 2015-04-02 FR FR1552852A patent/FR3034564B1/en not_active Expired - Fee Related
-
2016
- 2016-03-18 EP EP16712972.5A patent/EP3278330B1/en active Active
- 2016-03-18 WO PCT/FR2016/050615 patent/WO2016156697A1/en active Application Filing
- 2016-03-18 US US15/561,277 patent/US10306353B2/en active Active
Non-Patent Citations (1)
Title |
---|
None * |
Also Published As
Publication number | Publication date |
---|---|
US20180124501A1 (en) | 2018-05-03 |
FR3034564A1 (en) | 2016-10-07 |
US10306353B2 (en) | 2019-05-28 |
FR3034564B1 (en) | 2017-04-28 |
EP3278330A1 (en) | 2018-02-07 |
WO2016156697A1 (en) | 2016-10-06 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
EP0008274B1 (en) | Unidirectional acoustical enclosure | |
EP1222653B1 (en) | Underwater broadband acoustic transducer | |
EP3384486B1 (en) | Reflective acoustic metamaterial | |
FR2717031A1 (en) | Acoustic enclosure provided with an internal passive radiator. | |
EP3039672B1 (en) | Acoustic panel | |
EP3868602B1 (en) | Headrest comprising at least one speaker system | |
FR3043241A1 (en) | MULTI-WINDOW WINDOW INTEGRATING AN ACTIVE NOISE REDUCTION DEVICE | |
WO2017077236A1 (en) | Multi-glazed window incorporating a noise reduction device | |
WO1980001128A1 (en) | Electro acoustic transducer | |
EP3278330B1 (en) | Acoustic impedance matching device and loudspeaker provided with such a device | |
FR2955731A1 (en) | Acoustic enclosure for emitting acoustic waves, has viscoelastic membrane displaced under action of wavy excitation to attenuate stationary acoustic wave created by cavity, at or around resonance frequency | |
EP3469812B1 (en) | Electrodynamic broad band transducer for audio headphone and respective audio headphone | |
FR2504520A1 (en) | Composite formable panels for acoustic isolation of HF noise - involving macro:cellular layer with shaped perforation of one cover | |
EP3677051B1 (en) | Aquatic acoustic enclosure | |
FR2953635A1 (en) | Sound absorption device for aeronautic industry, has displacing unit displacing central block and plates between coincidence positions in which two intersecting sections of openings correspond to maximum absorption frequencies | |
EP2700247B1 (en) | Device for emitting an acoustic wave | |
FR2941122A1 (en) | Acoustic enclosure for emitting acoustic waves, has cavity originating stationary acoustic wave based on acoustic waves, and acoustic absorption unit including acoustic absorption at resonant frequency or around resonant frequency | |
FR2818421A1 (en) | Acoustic sandwich panel with several degrees of freedom has two or more cellular layers of different dimensions with porous separators | |
EP0335892B1 (en) | Method for correcting the amplitude/frequency response of an electro-acoustic transducing system and corresponding transducer assembly | |
EP2015391A1 (en) | Coaxial attenuator | |
FR2889021A1 (en) | Loudspeaker e.g. electromagnetic speaker, enclosure, has ports each extending along height of case and communicating with S-shaped baffle having input channel that converges so that output channel is terminated by diverging towards port | |
FR2664782A1 (en) | Omnidirectional acoustic enclosure | |
FR2941837A1 (en) | MOBILE CREW AND ELECTRODYNAMIC TRANSDUCER EQUIPPED WITH SUCH MOBILE CREW. | |
FR3068167A1 (en) | INSTRUMENT OF WIND MUSIC WITH FREE REEDS | |
FR3090206A1 (en) | Electromechanical actuator, vibrotactile button and surface loudspeaker comprising such an electromechanical actuator |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: THE INTERNATIONAL PUBLICATION HAS BEEN MADE |
|
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 |
|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: REQUEST FOR EXAMINATION WAS MADE |
|
17P | Request for examination filed |
Effective date: 20170928 |
|
AK | Designated contracting states |
Kind code of ref document: A1 Designated state(s): AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR |
|
AX | Request for extension of the european patent |
Extension state: BA ME |
|
RIN1 | Information on inventor provided before grant (corrected) |
Inventor name: HOSOI, SHINTARO |
|
DAV | Request for validation of the european patent (deleted) | ||
DAX | Request for extension of the european patent (deleted) | ||
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: EXAMINATION IS IN PROGRESS |
|
17Q | First examination report despatched |
Effective date: 20181017 |
|
REG | Reference to a national code |
Ref country code: DE Ref legal event code: R079 Ref document number: 602016053517 Country of ref document: DE Free format text: PREVIOUS MAIN CLASS: G10K0011160000 Ipc: G10K0011000000 |
|
GRAP | Despatch of communication of intention to grant a patent |
Free format text: ORIGINAL CODE: EPIDOSNIGR1 |
|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: GRANT OF PATENT IS INTENDED |
|
RIC1 | Information provided on ipc code assigned before grant |
Ipc: H04R 1/30 20060101ALI20201125BHEP Ipc: G10K 11/00 20060101AFI20201125BHEP Ipc: H04R 1/28 20060101ALI20201125BHEP |
|
INTG | Intention to grant announced |
Effective date: 20201217 |
|
GRAS | Grant fee paid |
Free format text: ORIGINAL CODE: EPIDOSNIGR3 |
|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: GRANT OF PATENT IS INTENDED |
|
GRAA | (expected) grant |
Free format text: ORIGINAL CODE: 0009210 |
|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: THE PATENT HAS BEEN GRANTED |
|
AK | Designated contracting states |
Kind code of ref document: B1 Designated state(s): AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR |
|
REG | Reference to a national code |
Ref country code: GB Ref legal event code: FG4D Free format text: NOT ENGLISH |
|
REG | Reference to a national code |
Ref country code: AT Ref legal event code: REF Ref document number: 1368068 Country of ref document: AT Kind code of ref document: T Effective date: 20210315 Ref country code: CH Ref legal event code: EP |
|
REG | Reference to a national code |
Ref country code: DE Ref legal event code: R096 Ref document number: 602016053517 Country of ref document: DE |
|
REG | Reference to a national code |
Ref country code: IE Ref legal event code: FG4D Free format text: LANGUAGE OF EP DOCUMENT: FRENCH |
|
REG | Reference to a national code |
Ref country code: LT Ref legal event code: MG9D |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: HR Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20210303 Ref country code: GR Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20210604 Ref country code: FI Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20210303 Ref country code: NO Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20210603 Ref country code: BG Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20210603 Ref country code: LT Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20210303 |
|
REG | Reference to a national code |
Ref country code: NL Ref legal event code: MP Effective date: 20210303 |
|
REG | Reference to a national code |
Ref country code: AT Ref legal event code: MK05 Ref document number: 1368068 Country of ref document: AT Kind code of ref document: T Effective date: 20210303 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: RS Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20210303 Ref country code: LV Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20210303 Ref country code: PL Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20210303 Ref country code: SE Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20210303 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: NL Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20210303 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: SM Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20210303 Ref country code: AT Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20210303 Ref country code: EE Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20210303 Ref country code: CZ Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20210303 |
|
REG | Reference to a national code |
Ref country code: CH Ref legal event code: PL |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: IS Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20210703 Ref country code: PT Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20210705 Ref country code: SK Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20210303 Ref country code: RO Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20210303 |
|
REG | Reference to a national code |
Ref country code: DE Ref legal event code: R097 Ref document number: 602016053517 Country of ref document: DE |
|
REG | Reference to a national code |
Ref country code: BE Ref legal event code: MM Effective date: 20210331 |
|
PLBE | No opposition filed within time limit |
Free format text: ORIGINAL CODE: 0009261 |
|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: DK Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20210303 Ref country code: AL Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20210303 Ref country code: CH Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20210331 Ref country code: MC Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20210303 Ref country code: LI Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20210331 Ref country code: LU Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20210318 Ref country code: ES Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20210303 Ref country code: IE Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20210318 |
|
26N | No opposition filed |
Effective date: 20211206 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: SI Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20210303 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: IS Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20210703 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: BE Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20210331 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: CY Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20210303 |
|
P01 | Opt-out of the competence of the unified patent court (upc) registered |
Effective date: 20230527 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: HU Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT; INVALID AB INITIO Effective date: 20160318 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: MK Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20210303 |
|
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: DE Payment date: 20240307 Year of fee payment: 9 Ref country code: GB Payment date: 20240325 Year of fee payment: 9 |
|
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: IT Payment date: 20240312 Year of fee payment: 9 Ref country code: FR Payment date: 20240328 Year of fee payment: 9 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: TR Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20210303 |