DE20321033U1 - Membrane driver for a loudspeaker, especially for automobile and aircraft sound systems, has a larger coil to take the magnet system within it and stabilize membrane vibration - Google Patents

Abstract

Loudspeaker membrane driver works as electrodynamic sound converter, with a magnet within a cage (1) with an oscillating coil (20). The magnet is in a ring, with inner diameter from 5 mm and outer diameter from 10 mm, composed of at least two pole plates of a magnetic material with thickness up to 15 mm, forming an outer (11) and an inner (7) air space The coil of the deep middle tone membrane (3,8) extends into the outer air space. The loudspeaker membrane driver works as an electrodynamic sound converter, with a magnet within a cage (1) with an oscillating coil (20). The magnet is in a ring, with an inner diameter from 5 mm and an outer diameter from 10 mm, composed of at least two pole plates of a magnetic material with a thickness up to 15 mm, forming an outer (11) and an inner (7) air space The coil of the deep middle tone membrane (3,8) extends into the outer air space. The magnet system (13) is positioned within the coil.

Description

The The invention relates to a speaker, which as electrodynamic Sound converter executed is, with at least a first magnet, a first membrane with a membrane outer edge, the one membrane outer edge plane spans, a first bead surrounding the first membrane to flexible storage of the first membrane, wherein the bead of a other material consists of the first membrane, a first voice coil, which is attached directly or indirectly to the first membrane and a magnet system having at least one first magnet, further a support structure (basket) for receiving the magnet system and the first membrane, wherein the first membrane over the first bead with the Support structure is connected, and the supporting structure to the Membrane-oriented front and an oppositely oriented back having.

Similar speakers are well known. By way of example, the German patent application DE 36 03 537 A1 directed. This document shows a full-range speaker with a membrane, which is driven by a voice coil and a permanent magnet, wherein the membrane has at its membrane outer edge a circumferential bead through which the membrane is flexibly supported. The bead is attached to a support structure, also called a basket, attached, wherein the support structure is also used to hold the entire centrally arranged magnet system. The membrane is in this case thus formed opposite to the sound preferred direction of the speaker and forms a kind of funnel, at the top of the magnet system is arranged so that a total of the basket and the magnet system located outside the basket a large installation depth is necessary.

by virtue of the today required problem-free mounting options of speakers, for example in the car or Aerospace industry, however, is required that speakers be as flat as possible and are not very demanding, or as possible flat surfaces, for example on car doors or dressings without special preparation, be attached can. Today's doors a motor vehicle are usually kept very flat and have a variety of wiring harnesses and electrical systems that use the existing space and cavity largely complete. In addition requires the guide and mechanics of the discs and the closing mechanism of the door with the necessary bracing for the side impact protection often huge Space, so that the desired there Installing a speaker often on big Difficulties are encountered.

alternative it is possible, the speakers in other places, for example in the footwell or in the dashboard, to install. However, this also exists in principle a space problem, in addition the acoustic quality unfavorable Positioning badly suffers.

On The market is covered by various flat speaker systems other design principles, however, such systems often have one too low efficiency and too low bandwidth. Of There is also a large one mechanical vulnerability, no temperature resistance or a temperature-dependent acoustic behavior.

It will also continue on to the patent DE 36 38 727 C2 In this embodiment, the acoustic quality is impaired by the fact that in the area of the preferred sound propagation the magnet system is mounted in front of the diaphragm and therefore the undisturbed propagation of sound is hindered. In addition, a stable and attachment of the magnet system is difficult, since a compromise between stability of the carrier for the magnet system and free sound propagation must be received.

It The object of the invention to provide a speaker, the on the one hand after the proven simple system of electrodynamic sound transformation with permanent magnet and voice coil works, however, the modern requirements for flat Construction and high acoustic quality.

The Task is solved by the features of the protection claim 1. advantageous Embodiments of the invention are in the dependent claims and the Figures including Description given.

The inventor has recognized that a solution to the above-mentioned problem can be achieved by providing the loudspeaker with a curved sound propagating membrane driven by a voice coil and a magnet, the magnet system being at least partially immersed in the membrane Volume dips, creating a very flat design of the support structure or basket is possible. In this case, a magnet system is used with at least one permanent magnet which forms an annular gap, optionally by means of the aid of a yoke or another magnet, wherein the voice coil can dip into this annular gap. The magnet system can approach very close to the membrane are brought so that the membrane outer edge surface formed by the outer edge of the membrane is cut by the magnet system. On the one hand, this produces an extremely flat design of the magnet. On the other hand, a very good and broadband acoustic characteristics of the speaker system is obtained.

• – einem ersten Magneten,
• – einer ersten Membran mit einem Membranaußenrand, der eine Membranaußenrandebene aufspannt,
• – einer die erste Membran umlaufenden ersten Sicke zur flexiblen Lagerung der ersten Membran, wobei die Sicke aus einem anderen Material besteht als die erste Membran,
• einer ersten Schwingspule, die mittelbar oder unmittelbar an der ersten Membran befestigt ist, und
• – einem Magnetsystem mit mindestens einem ersten Magneten (Permanentmagneten), weiterhin
• – einer Tragkonstruktion (Korb) zur Aufnahme des Magnetsystems und der ersten Membran, wobei die erste Membran über die erste Sicke mit der Tragkonstruktion verbunden ist, und die Tragkonstruktion eine zur Membran orientierte Vorderseite (Schallausbreitungsvorzugsrichtung) und eine entgegengesetzt orientierte Rückseite aufweist, dahingehend zu verbessern, dass
• – die erste Membran zumindest teilweise nach oben erhaben ausgebildet ist und der Bereich der ersten Membran, an der die erste Schwingspule befestigt ist, vor der Membranaußenrandebene angeordnet ist, wobei
• – die erste Membran einen Durchmesser aufweist, der größer ist als der Durchmesser der ersten Schwingspule, die diese Membran bewegt,
• – der erste Ringspalt in Richtung Membran einen verengten parallelen Bereich aufweist, und
• – das gesamte Magnetsystem vor der Tragkonstruktion (=Korb) angeordnet ist.

On the basis of these underlying considerations, the inventor proposes that the loudspeakers known per se be composed at least of:

• A first magnet,
• A first membrane having a membrane outer edge which spans a membrane outer edge plane,
• A first bead encircling the first membrane for flexibly supporting the first membrane, the bead being made of a different material than the first membrane,
• a first voice coil directly or indirectly attached to the first diaphragm, and
• - A magnet system with at least a first magnet (permanent magnet), continue
• - A supporting structure (basket) for receiving the magnet system and the first membrane, wherein the first membrane is connected via the first bead to the support structure, and the support structure has a membrane-oriented front (sound propagation preferential direction) and an oppositely oriented back to improve to that effect that
• - The first membrane is at least partially raised to the top and the region of the first membrane to which the first voice coil is mounted, is arranged in front of the membrane outer edge plane, wherein
• The first diaphragm has a diameter that is greater than the diameter of the first voice coil that moves this diaphragm,
• - The first annular gap in the direction of the membrane has a narrowed parallel region, and
• - The entire magnet system in front of the supporting structure (= basket) is arranged.

By This construction is extremely flat and also compact design of the speaker system possible, so that he is especially for suitable for mounting in vehicles. However, other applications are also which require a flat design of the speaker system, possible.

In a particularly preferred embodiment of Speaker beats the inventor before that the magnet system, the membrane outer edge plane at least cuts or possibly even above the membrane outer edge plane is arranged. This means So that the magnet system at least partially within the is located by the membrane spanned volume.

The Magnetic system may preferably have a first annular gap, in which the first voice coil can dip. This will be a special good leadership reached. If the voice coil designed sufficiently large, so can stabilize the natural vibration behavior of the membrane much better and the membrane can be made very flat and thin. hereby increases the efficiency of the system and the stroke of the diaphragm can be reduced.

In a further variant of the speaker can additionally be provided be to arrange at least one further membrane within the first membrane, so that thereby a multi-way system can be realized. there can the magnet system as well have at least one further annular gap, in each case one additional voice coil for can immerse another membrane.

The first membrane may also have an internal further bead, which is connected to the magnet system, so that thereby an additional Centering of the membrane is achieved.

The Membrane can also be made in several parts. This has the advantage that thereby the central area designed with other lighter materials can be achieved so that better dynamics at high frequencies becomes.

hereby and by a corresponding embodiment of the magnet system can the speaker not only as a one-way system, but also as a two-way, three- or reusable system be designed.

A further advantageous embodiment of the speaker can therein exist that the magnet system at least one ring magnet and at least a pole plate, which form the at least one air gap.

In addition, can the magnet system consists of several ring magnets, a lower pole plate and each magnet of an upper pole plate are formed, wherein the Air gaps are arranged between the pole plates. Through this Design of the magnet system is a very effective multi-way system possible, wherein the inner annular gap is provided for driving a tweeter.

Even though in the speaker according to the invention It is also possible to dispense with special centerings these in special cases advantageous, especially if the size requires additional centering. The magnets of the magnet system can annular from the respective associated Enclosed voice coil.

Of further it can be cheap be when the pole plates of the magnet system made of magnetic material are manufactured, since this high flux density with well-defined Field lines in the region of the air gap can be generated.

In a special design The magnetic system can be configured such that a Ring magnet within a larger and at the same time outside a smaller voice coil is located. Is particularly favorable it in this case to perform the rear pole plate as a magnetic yoke, so that a narrow air gap through the front and rear pole plate, both inside and outside of the ring magnet is formed.

The materials of the permanent magnet can be very different variants. However, particularly advantageous are neodymium - iron or neodymium - iron - boron or rare earths - cobalt (eg SmCo _5, Sm ₂ Co _{1 7)} or other hard ferrites.

Regarding the Construction of the speaker beats the inventor before that at least one magnet at least one Screw and / or adhesive and / or clamping elements on the membrane basket is attached, and combinations of these mounting options be proposed.

Regarding the Design of the membrane suggests the inventor before that this example of a foamed material may exist, which preferably with a one- or two-sided barrier layer is provided. For example, this may be an aluminum and magnesium foam, polystyrene foam, PVC, polyolefin material, Polyurethane, polyester, styrofoam or sandwich panels with honeycomb construction act.

A another variant of the embodiment of the membrane or a part of Membrane may consist of being made of a shaped film or sandwich products, preferably polyester, polyimide, Bextrenen, polycarbonate, aluminum, magnesium, polypropylene, paper, Fibers, Kevlar, carbon fiber, glass fiber, Nomex or mixed products the aforementioned materials is produced.

In addition, can on at least one membrane, preferably the single membrane, an invers shaped Dust Cap, also Dome, Dome or Dust Cover called, be arranged.

The at least one intended bead can be made of rubber, for example or coated foam material, fiber materials or paper getting produced.

in the central region of a membrane, the above-mentioned "Dust Cap" be attached, wherein behind it a centering, for example made of spring steel or Fiber materials can be located.

In Reference to the supporting structure or the basket suggests the inventor before that this example of plastics or metal materials is made, it is advantageous to the basket with openings to provide a physical coupling to the back Air volume an optionally existing panel or a Housing too cause.

exemplary can the back of the basket executed as a level be so that behind the speaker no openings for installation necessary are. However, there is also the possibility of the back of the basket as a flat truncated cone, preferably with a slope of maximum 20 °, preferably not more than 10 °, across from the level.

To the Furthermore, protection of the membrane can provide a protective grid in front of the membrane be provided, as is common practice in the art.

Regarding the proportions of the speaker in a preferred embodiment, the inventor proposes the ratio B / T of greatest breadth B the largest membrane of the loudspeaker to the greatest depth of the speaker T with respect to the components membrane and magnet system greater than 3/1, preferably greater than 5/1, preferably greater than 10/1, is.

in the The following is the invention with reference to the preferred embodiments with the help of the figures closer described. They show in detail:

1 : One-way speaker with a permanent magnet;

2 : One way speaker with a permanent magnet and dust cap;

3 : Variants of membrane shaping in a one-way loudspeaker with a permanent magnet;

4 : One-way speaker with a permanent magnet and centering as a metal spring;

5 : One-way loudspeaker with a permanent magnet and centering of tissue;

6 : Two-way loudspeakers with a permanent magnet and central tweeter;

7 : One way speaker with two permanent magnets;

8th : One way speaker with two permanent magnets and dust cap;

9 : Two-way loudspeakers with three permanent magnets and central tweeter;

10 : Two-way speaker with three permanent magnets and slightly conical basket;

11 : Magnified magnet system off 5 ;

12 : View from the back on the basket;

13 : Front view of diaphragm and central tweeter with peripheral screw holes;

14 : Front view of diaphragm and central tweeter with no screw holes on the outside.

The 1 shows a section through a simple broadband and inventively designed speaker with a single membrane 2 on a flat basket 1 , which is flat on the back, is stretched. The membrane 2 is on its outer edge 32 through a bead 3 with the basket 1 connected and tensioned by its outer edge 32 an outer edge plane 30 on. On the front of the basket 1 is a magnet system 4 attached, which consists of an annular permanent magnet 5 consists, the front of a likewise annular pole plate 6 and on the back one to a yoke 13 expiring rear pole plate 7 features. Between the yoke 13 the rear pole plate 7 and the front pole plate 6 An air gap is created 8th into the voice coil 9 that with the membrane 2 in the area 28 connected, can dip. Thus, in a known manner by electrical impulses the membrane 2 are stimulated to movements and sound are generated.

The sound propagation preferential direction, which also defines the front of the loudspeaker, is indicated by the arrow 33 indicated. Furthermore, the outer diameter D of the membrane is on the right 2 and the smaller diameter d of the associated voice coil 9 indicated on the right. According to the invention in this embodiment, the magnet system 4 due to the curvature of the membrane 2 and the near attachment of the voice coil 9 moved strongly forward, leaving the front pole plate 6 and the effective area of the yoke 13 that the air gap 8th form in front of the membrane outer edge plane 30 lie; the permanent magnet 5 is from the membrane outer edge plane 30 cut. As a result, an extremely flat design of the speaker is possible.

It should also be noted that, especially in loudspeakers with larger diameters, the permanent magnet 5 or the entire magnet system 4 may even be completely in front of the membrane outer edge plane.

The 2 shows a similar embodiment of a broadband one-way speaker, but in this version is the membrane 2 in a central area by a lighter concave material 12 been replaced. Replacement of the central part of a membrane 2 lighter material has the advantage that the inertial mass of the membrane is thereby reduced and the usable frequency range of the loudspeaker can be extended to higher frequencies.

The 3 shows a further variant of a one-way system, similar to the execution of 1 , In this case, the 3 have been divided into an upper and a lower variant of a membrane design. The upper variant of the membrane design shows a flat conical diaphragm 2 that from the outside beading 3 leads to the area of the voice coil and then has a slightly concave shape in the central area. In addition, the membrane has a centering 20 , which is designed here in the form of a metal spring. The lower parts of the 3 shows another exemplary form of the membrane 2 , which initially runs largely flat on the edge, then experiences an increase with a maximum in the area of the voice coil and is again concave in the central area.

The 4 again shows the same membrane contours as the 3 , however, are the edges arranged beads 3 equipped with several wavy lines while in the 3 only one survey for the bead is provided. The centering 20 the membrane 2 in the 4 is shown here, for example, consists of a fabric material.

Another embodiment of the speaker according to the invention is in the 5 shown. This shows a section through a two-way loudspeaker according to the invention, in which case the outer membrane 2 the execution 2 However, in the central area is an additional tweeter in the magnet system 4 been integrated. For this purpose, the magnet system from the 1 or 2 changed so that the rear pole plate a second, central yoke 14 which, in conjunction with the front pole plate 6 a second air gap 15 forms. In this air gap, a second voice coil 17 immerse which is a thin high-tone membrane 18 drives. The high-tone membrane 18 This is about a bead 19 at the front pole plate 6 of the magnet system 4 attached.

The 6 shows again a modification of the two-way loudspeaker according to the invention from the 5 , in which case the outer membrane 2 in their two illustrated variants of the membrane forms of the 3 equivalent. However, due to the tweeter now centrally located in the magnet system, an additional flexible attachment of the outer membrane 2 through another internal bead 21 made, with the inner part of this bead 21 on the front pole plate 6 of the magnet system 4 is attached. The design of the magnet system again corresponds to that already in 5 shown execution.

In the 7 another variant of a one-way speaker according to the invention is shown. Basically, the shape of the speaker's design matches 1 , where the essential difference is in the magnet system. Here is instead of a single permanent magnet 5 both an inner permanent magnet 5 as well as another outer ring permanent magnet 22 provided, both permanent magnets on front pole plates 6 and 23 between which the only air gap 8th is formed. In this construction, it is now possible to dispense with the rear pole plate, as shown in the previously shown magnetic systems. The advantage of such an embodiment is essentially that this design without reflux makes it possible to significantly reduce the overall height of the magnet system or on the other hand to achieve a very large stroke at the same height.

In the 8th is another sectional view of a one-way speaker shown having the same magnet system with two ring magnets as 7 , wherein the formation of the membrane is in turn designed so that in the central region a so-called "dust cap" is present, which reduces the inertial mass of the oscillating membrane.

According to the design of the magnet system from the 7 and 8th , show the 9 a development with additionally arranged inside tweeters, wherein the voice coil of the tweeter again a third permanent magnet 25 with front pole plate 26 is shown and between the central front pole plate 26 and the middle pole plate 23 the air gap for the voice coil 17 the tweeter 24 is formed.

In contrast to the figures shown above, in the 10 a basket 1 shown, which is not flat on its rear side, but formed curved against the Schallvorzugsrichtung of the speaker. Such a slight curvature, which however should have a maximum angle a from the plane of not more than 20 °, preferably not more than 10 °, preferably not more than 5 °, may be helpful if a particularly flat design of the loudspeaker, due to special installation situations, is necessary.

Basically, the speaker shown here with the execution of the 9 However, it should be noted that such a variation is also possible for all previously shown speakers.

The 11 shows an enlarged view of the magnet system of the 6 , This magnet system has a ring-shaped permanent magnet 5 on. On the back there is a pole plate, which is on both sides in front of the first yoke 13 and a second yoke 14 is trained. On the front of the permanent magnet 5 There is another pole plate, which together with the first and the second yoke, a first air gap 8th and a second internal air gap 15 form. In the outer air gap 8th dives a voice coil 9 one that is responsible for driving the outer membrane 2 is responsible while in the inner air gap 15 the voice coil 17 the tweeter 24 dips. The tweeter 24 is with a high-tone membrane 18 equipped, which at the outer edge over a small bead 19 features that with the pole plate 6 connected is. In addition, in the 11 nor the, of course, in all other speaker systems existing but not explicitly shown, electrical connections 31 represented for the voice coils. In the illustrated version, a damping element is preferably in the central region of the magnet system 27 used, which may for example consist of foam or soft rubber.

The rear view of an exemplary loudspeaker according to the invention is shown in FIG 12 shown. It essentially shows the basket 1 with the here symmetrically arranged rear openings 10 in the basket 1 and the four screw holes 11 , It should be noted that, of course, other designs and contours of the openings are within the scope of the invention. In particular, it is also pointed out that the loudspeaker according to the invention not only has to have a round outer shape, but also oval, quadrangular or other per se known contours are possible.

In the 13 and 14 is the supervision of a two-way speaker according to the invention shown, in which case the optional protective grille is not shown here for a better view. The 13 also has four screw holes 11 , for fixing the speaker, while in the 14 an execution of the basket 1 is shown without screw holes.

It It should also be pointed out that the loudspeaker according to the invention, the principle of the spring-mass system or the dynamic loudspeaker works, so via a voice coil in the air gap has a permanent magnet, across from the usual Systems usually has a much larger voice coil and thereby makes it possible to position the magnet system within the voice coil.

These larger voice coil has the further advantage that the membrane continues on the outer diameter is driven. As a result, the natural vibration behavior of the membrane significantly stabilized or reduced and she can thereby much flatter, lighter and thinner designed. Of the Hub of the voice coil is, for example, depending on the requirements and Size, between 0.5 and 20 mm +/- and the diameter is 10 mm to 100 mm at a winding height from about 1 mm.

In an exemplary embodiment of the speaker with additional tweeter can the air gap for the outer membrane with coil between 0.1 mm to 3 mm and the air gap of the coil for the tweeter accordingly bigger, between 0.2 mm to 4 mm become. This allows one to compare the efficiency of the two systems to adjust. The voice coil for the tweeter can advantageously following dimensions Have diameter between 6 mm and 50 mm, height from 0.1 to 10mm +/- and a stroke of 0.1 to 5 mm +/-.

In addition will noted that the voice coil used with a or more coil layers, preferably two-ply, and also with and without carriers can be trained.

It it is understood that the above features of the invention not only in the specified combination, but also in others Combinations or alone, without the frame to leave the invention.

All in all Thus, the invention provides a very flat speaker system proposed, which is particularly simple and despite all very flat design distinguishes. Due to the use of the very proven and effective dive coil system is also a very high speaker efficiency and big acoustic quality to reach.

1

basket

2

membrane

3

Beading

4

magnet system

5

permanent magnet

6

Front pole plate

7

Rear Pole plate with yoke

8th

air gap

9

voice coil

10

opening

11

screw holes

12

Dust Cap

13

first yoke

14

second yoke

15

second air gap

16

Second membrane

17

Second voice coil

18

Tweeter diaphragm

19

Beading for tweeters

20

centering

21

Second bead of the outer membrane 2

22

second permanent magnet

23

Second front pole plate

24

tweeter

25

third permanent magnet

26

third front pole plate

27

damping element

28

fastening area the first voice coil

29

guard

30

Membrane outer edge plane

31

electrical connection

32

Membrane outer edge

33

Sound propagation preferred direction

D

outer diameter the outer membrane

d

diameter

T

overall depth of membrane and magnet system

α

cone angle of the basket to the plane

Claims (29)

Loudspeaker, designed as an electrodynamic transducer, consisting of at least: 1.1. a first magnet ( 5 1.2. a first membrane ( 2 ) with a membrane outer edge ( 32 ), which has a membrane outer edge plane ( 30 ), 1.3. one the first membrane ( 2 ) circumferential first bead ( 3 ) for flexible storage of the first membrane ( 2 ), wherein the bead is made of a different material than the first membrane, 1.4. a first voice coil ( 9 ) directly or indirectly on the first membrane ( 2 ), and 1.5. a magnet system ( 4 ) with at least one first magnet ( 5 ) and at least one first annular gap, in which the first voice coil dives, continue 1.6. a supporting structure (basket) (basket) 1 ) to record of the first magnet system ( 4 ) and the first membrane, wherein the first membrane is connected to the supporting structure via the first bead, and the supporting structure has a membrane-oriented front side and an oppositely oriented rear side, characterized in that 1.7. the first membrane ( 2 ) in one piece and at least partially to the front, in the direction of the sound preferred direction ( 33 ), has a curvature and the area ( 28 ) of the first membrane ( 2 ), to which the first voice coil is attached, in front of the membrane outer edge plane ( 30 ), 1.8. the first membrane ( 2 ) has a diameter (D) which is greater than the diameter of the first voice coil (d), this membrane ( 2 ), 1.9. the first annular gap ( 8th ) has a narrowed parallel region towards the membrane, and 1.10. the entire magnet system in front of the supporting structure (basket) ( 1 ) is arranged. Loudspeaker according to the above protection claim 1, characterized in that the magnet system ( 4 ) the membrane outer edge plane ( 30 ) cuts. Loudspeaker according to the above protection claim 1, characterized in that the magnet system ( 4 ) in front of the membrane outer edge plane ( 30 ) is arranged. Loudspeaker according to one of the preceding claims 1 to 3, characterized in that within the first diaphragm ( 2 ) at least one further membrane ( 18 ) is arranged. Loudspeaker according to one of the preceding claims 1 to 4, characterized in that the magnet system ( 4 ) at least one further annular gap ( 15 ), in each of which a further voice coil ( 17 ) for another membrane ( 18 ), wherein preferably this further annular gap ( 15 ) has a narrowed parallel region in the direction of the membrane. Loudspeaker according to one of the preceding claims 1 to 5, characterized in that the first diaphragm ( 2 ) an inner further bead ( 21 ), via which they are connected to the magnet system ( 4 ) connected is. Loudspeaker according to one of the preceding claims 1 to 6, characterized in that the magnet system ( 4 ) at least one ring magnet ( 5 ) and at least one pole plate ( 6 ) having the at least one air gap ( 8th ) form. Loudspeaker according to one of the preceding claims 1 to 7 , characterized in that the magnet system comprises a plurality of ring magnets ( 5 . 22 . 25 ), a rear pole plate ( 7 ) and each magnet has a front pole plate ( 6 . 23 . 26 ), wherein the air gaps ( 8th . 15 ) are arranged between the pole plates. Loudspeaker according to one of the preceding claims 1 to 8, characterized in that on at least one membrane ( 2 ) a centering is mounted. Loudspeaker according to one of the preceding claims 1 to 9, characterized in that the magnets ( 5 . 22 . 25 ) in each case annularly from the associated voice coil ( 9 . 17 ) are enclosed. Loudspeaker according to one of the preceding claims 1 to 10, characterized in that the magnet system ( 4 ) Pole plates ( 6 . 7 . 23 . 26 ) of magnetic material. Loudspeaker according to one of the preceding claims 1 to 11, characterized in that at least one ring magnet ( 22 ) within a larger and at the same time outside of a smaller voice coil ( 9 . 17 ) is located. Loudspeaker according to one of the preceding claims 1 to 12, characterized in that a ring magnet ( 5 ) at least two pole plates ( 6 . 7 ), of which the rear pole plate ( 7 ) surrounds the magnet annularly and with the front pole plate ( 6 ) an outer and inner air gap ( 8th . 15 ). Loudspeaker according to one of the preceding claims 1 to 13 in that at least one magnet is made of neodymium iron or neodymium iron boron or rare earth cobalt (SmCo ₅ or Sm ₂ Co ₁₇ ) or hard ferrites. Speakers according to one the preceding claims 1 to 14, characterized in that at least one magnet at least with at least one screw and / or adhesive and / or at least a clamping elements (snap in, clipped) attached to the membrane basket becomes. Speakers according to one the preceding claims 1 to 15, characterized in that at least one membrane made of foamed Material consists, preferably with a one- or two-sided Barrier layer is provided, preferably made of aluminum and magnesium foam, polystyrene - rigid foam, PVC, polyolefin, polyurethane, polyester, styrofoam or sandwich panels with honeycomb construction. Loudspeaker according to one of the preceding claims 1 to 16, characterized in that at least one membrane ( 2 ) consists of specially shaped films or sandwich products, preferably of polyester, polyimide, Bextrenen, polycarbonate, aluminum, magnesium, polypropylene, paper, fiber, carbon fiber, glass fiber, or of mixed products these materials. Loudspeaker according to one of the preceding claims 1 to 17, characterized in that on a membrane ( 2 ) an inverted-shaped Dust Cap (dome, dome or dust cap) ( 12 ) is arranged. Loudspeaker according to one of the preceding claims 1 to 18, characterized in that at least one bead ( 3 . 19 . 21 ) is made of rubber or coated foam material, fiber materials or paper. Loudspeaker according to one of the preceding claims 1 to 19, characterized in that the basket ( 1 ) is made of plastics or metal materials. Loudspeaker according to one of the preceding claims 1 to 20, characterized in that the basket ( 1 ) Openings ( 10 ) for physical coupling to the rear air volume, casing or housing comprises. Loudspeaker according to one of the preceding claims 1 to 21, characterized in that the back of the basket ( 1 ) is flat. Loudspeaker according to one of the preceding claims 1 to 22, characterized in that the back of the basket ( 1 ) is designed as a truncated cone, preferably with a slope of not more than 20 °, preferably not more than 10 °, relative to the plane. Loudspeaker according to one of the preceding claims 1 to 23, characterized in that a protective grid ( 29 ) is provided in front of the membrane. Loudspeaker according to one of the preceding claims 1 to 24, characterized in that the ratio B / T or D / T of greatest width B or diameter D of the outer membrane ( 2 ) of the loudspeaker to the greatest depth of the loudspeaker T in relation to the components membrane and magnet system is greater than 3/1, preferably greater than 5/1, preferably greater than 10/1. Loudspeaker according to one of the preceding claims 1 to 25, characterized in that at least one front pole plate ( 6 . 23 . 26 ) completely in front of the membrane outer edge plane ( 39 ) is arranged. Loudspeaker according to one of the preceding claims 1 to 26, characterized in that at least one permanent magnet ( 5 . 22 . 25 ) in front of the membrane outer edge plane ( 39 ) is arranged. Loudspeaker according to one of the preceding claims 1 to 27, characterized in that the magnet system ( 4 ) has no rear pole plate. Loudspeaker according to one of the preceding claims 1 to 28, characterized in that the outer bead ( 3 ) has on average several surveys.