Omnidirectional loudspeaker and compression driver therefor

Abstract

A compression driver for an omnidirectional loudspeaker includes a motor assembly and a dome diaphragm coaxially disposed above and operably connected to the motor assembly, the diaphragm having a convex surface and a concave surface. The compression driver includes a phase plug having a top portion and a bottom portion, the bottom portion having a concave bottom surface disposed adjacent to the convex surface of the diaphragm and defining a compression chamber therebetween. The phase plug includes a plurality of conduits extending through the bottom portion for sound wave travel and converging to form an annular outlet, the top portion including a plurality of radially expanding channels acoustically connected to the annular outlet. Actuation of the diaphragm by the motor assembly generates sound waves within the compression chamber, the sound waves traveling through the annular outlet and the radially expanding channels to produce a generally horizontal 360° radiation pattern of sound waves from the compression driver.

Description

Technical Field

[0001] The implementation scheme relates to an omnidirectional loudspeaker and a compression driver with a dome diaphragm for the omnidirectional loudspeaker. Background Technology

[0002] An ideal omnidirectional loudspeaker radiates sound similarly in all directions and, from an acoustic point of view, behaves like a pulsating sphere. Typically, in practical applications, omnidirectionality is provided in the horizontal plane. Omnidirectional transducers and the loudspeaker systems containing them are used in a variety of applications, such as Hi-Fi loudspeakers, alarm systems, landscape loudspeaker systems, and Bluetooth-based portable audio loudspeakers.

[0003] A typical omnidirectional loudspeaker system consists of a direct-radiating transducer with a conical or dome-shaped diaphragm and a corresponding "diffuser" that propagates sound waves omnidirectionally. The transducer is oriented vertically along the diaphragm axis, thus converting the sound radiation into a distribution in the horizontal plane. Unfortunately, direct-radiating transducers are inefficient, at best only a few percent. This limits the efficiency, sensitivity, and maximum sound pressure level of transducers and loudspeaker systems that provide omnidirectional radiation. Furthermore, existing loudspeaker systems for omnidirectional purposes typically include directional loudspeaker arrays, and these systems have cancellation regions between the individual loudspeakers, which result in non-uniform coverage patterns and performance degradation. Summary of the Invention

[0004] In one or more embodiments, a compression driver for an omnidirectional loudspeaker includes a motor assembly and a domed diaphragm coaxially disposed above and operatively connected to the motor assembly, the diaphragm having convex and concave surfaces. The compression driver also includes a phase-shifting plug having a bottom portion and a top portion, the bottom portion having a concave bottom surface disposed adjacent to the convex surface of the diaphragm and defining a compression chamber therebetween. The phase-shifting plug includes a plurality of converging conduits extending through the bottom portion for sound wave propagation, the converging conduits forming an annular outlet, and the top portion including a plurality of radially extending channels acoustically connected to the annular outlet. Actuation of the diaphragm by the motor assembly generates sound waves within the compression chamber, the sound waves traveling through the annular outlet and the radially extending channels to produce a generally horizontal 360° radiation pattern of sound waves from the compression driver.

[0005] In one or more embodiments, the omnidirectional loudspeaker includes a lower horn member having a generally convex, upward-facing outer wall and an upper horn member spaced apart from the lower horn member and having a generally convex, downward-facing outer wall. At least one compression driver is connected along a central axis to one of the lower or upper horn members and includes: a motor assembly; a dome diaphragm operatively connected to the motor assembly and having a convex and a concave surface; and a phase-modulating plug having a bottom portion and a top portion, the bottom portion having a concave bottom surface adjacent to the convex surface of the diaphragm and defining a compression chamber therebetween. The lower and upper horn members are spaced apart along a central axis via at least one compression driver to define a channel for radiating sound waves generated by at least one compression driver in a generally horizontal 360° radiation pattern.

[0006] In one or more embodiments, the omnidirectional loudspeaker includes a lower horn member having a generally convex, upward-facing outer wall and an upper horn member spaced apart from the lower horn member and having a generally convex, downward-facing outer wall. A compression actuator is connected along a central axis to one of the lower or upper horn members and includes a motor assembly; a dome diaphragm operatively connected to the motor assembly and having a convex and a concave surface; and a phase-shifting plug having a bottom portion and a top portion. The bottom portion has a concave bottom surface adjacent to the convex surface of the diaphragm, thereby defining a compression chamber therebetween. The phase-shifting plug includes a plurality of converging conduits extending through the bottom portion for sound wave propagation, the converging conduits converging to form an annular outlet, and the top portion including a plurality of radially extending channels acoustically connected to the annular outlet. Sound waves are generated within the compression chamber by actuation of the diaphragm by the motor assembly, the sound waves traveling through the annular outlet and the radially extending channels. The lower and upper horn components are connected in a spaced-apart relationship along the central axis via a compression driver to define a channel for radiating sound waves generated by the compression driver in a generally horizontal 360° radiation pattern. Attached Figure Description

[0007] Figure 1 It is a cross-sectional view of a compression driver for an omnidirectional loudspeaker according to one or more embodiments;

[0008] Figure 2 yes Figure 1 A perspective view of the compression drive;

[0009] Figure 3 It is a top view of the phase-shifting plug of a compression driver according to one or more embodiments;

[0010] Figure 4 yes Figure 3 A bottom view of the phase-shifting plug;

[0011] Figure 5It is an exploded perspective view of a compression driver according to one or more implementation schemes;

[0012] Figure 6 yes Figure 5 Bottom exploded perspective view of the compression drive;

[0013] Figure 7 It is an exploded view of an omnidirectional loudspeaker including a compression driver, a lower horn component, and an upper horn component;

[0014] Figure 8 It is a cross-sectional view of an omnidirectional loudspeaker assembled according to one or more embodiments;

[0015] Figure 9 It is a cross-sectional view of an omnidirectional loudspeaker with dual compression drivers; and

[0016] Figure 10 It is a perspective view of an omnidirectional loudspeaker assembled according to one or more embodiments. Detailed Implementation

[0017] As requested, detailed embodiments of the invention are disclosed herein; however, it should be understood that the disclosed embodiments are merely examples of the invention that may be embodied in various alternative forms. The drawings are not necessarily drawn to scale; some features may be enlarged or minimized to show details of specific components. Therefore, the specific structural and functional details disclosed herein should not be construed as limiting, but merely as a representative basis for teaching those skilled in the art to apply the invention in different ways.

[0018] Existing omnidirectional loudspeakers are typically based on direct radiating transducers. In one or more embodiments, this document discloses an omnidirectional loudspeaker that efficiently and effectively generates sound using a compression driver with a generally horizontal 360° radiation pattern. Specifically, the embodiments disclosed herein are based on a compression driver with a dome diaphragm, wherein the disclosed compression driver has significantly higher efficiency compared to direct radiating transducers.

[0019] There are differences between compression drivers based on annular and dome diaphragms. Annular diaphragms are typically thermoformed from polymer films, while dome diaphragms are typically made from stamped aluminum, magnesium, titanium, or beryllium foil. Therefore, annular diaphragms have higher internal damping. Due to the lower density of polymer films, annular diaphragms have lower moving mass for a voice coil of the same diameter. Furthermore, dome diaphragms typically have a larger effective area for a voice coil of the same diameter. Annular diaphragms have higher mechanical compliance than dome diaphragms. In other words, dome diaphragms are generally stiff and heavy, while annular diaphragms are generally soft and light. Generally, for a voice coil of the same diameter, compression drivers using dome diaphragms are a better choice for bidirectional loudspeaker systems because they have a lower fundamental resonance compared to drivers based on annular curved diaphragms.

[0020] However, existing dome-diaphragm-based compression drivers typically have multiple concentric inputs to a phase-shifting plug, which merge into a circular outlet of the driver. This configuration prevents the phase-shifting plug from having a radial outlet. The embodiments disclosed herein include a compression driver consisting of a dome diaphragm and an annular outlet that radially directs sound waves for use with an omnidirectional loudspeaker.

[0021] First refer to Figures 1 to 6 The diagram illustrates a compression driver 100, which includes a motor assembly 102, a dome diaphragm 104 disposed above and operatively connected to the motor assembly 102, and a phase-shifting plug 106 coaxially disposed above the diaphragm 104 along a central axis 108. In one or more embodiments, the motor assembly 102 may include an annular permanent magnet 110 disposed between an annular top plate 112 and a back plate 114, but the motor assembly 102 is not limited to this configuration. As is known in the art, the motor assembly 102 provides a permanent magnetic field for electrically coupled to a voice coil (not shown), wherein the voice coil is mechanically coupled to the diaphragm 104 and generates movement of a flexible portion of the diaphragm 104 to convert a received electrical signal into sound waves propagating from the compression driver 100.

[0022] The phase-shifting plug 106 includes a bottom portion 116 and a top portion 118 arranged generally symmetrically about a central axis 108. The top portion 118 may have a generally constant height above the bottom portion 116, and the top portion 118 may be integrally formed with or attached to the bottom portion 116 by any suitable means. The bottom portion 116 may be generally circular or may have any other suitable geometry. The bottom portion 116 may be coupled to or mounted to the backplate 114 of the motor assembly 102. The motor assembly 102, diaphragm 104, and phase-shifting plug 106 may be, for example, connected via a mounting hole 120 (…). Figure 5 The fasteners are connected together.

[0023] The dome diaphragm 104 has a concave lower surface 122 and a convex upper surface 124. Unlike typical compression actuators with dome diaphragms where the acoustic signal is guided by a phase-modulating plug adjacent to the dome's concave surface, in one or more embodiments disclosed herein, the acoustic signal can enter the phase-modulating plug 106 from the convex surface 124 of the dome diaphragm 104. This configuration advantageously increases the total effective area of ​​the diaphragm 104 without increasing the moving mass, as the surrounding area can also be used as a radiating area. The bottom portion 116 of the phase-modulating plug 106 includes a bottom surface 126 facing the convex surface 124 of the diaphragm 104 and an opposing top surface 128. The bottom surface 126 may be generally concave, complementary to the convex surface 124 of the diaphragm 104, while the top surface 128 may be generally planar. It should be understood that any directional terms used herein are used only to indicate the relative placement of the various components of the compression actuator 100 and are not intended to be limiting.

[0024] In the compression actuator, diaphragm 104 is loaded by a compression chamber, which is a thin layer of air separating diaphragm 104 from phase-shifting plug 106. In one or more embodiments, compression chamber 130 is defined in the space between the convex surface 124 of diaphragm 104 and the concave bottom surface 126 of the bottom portion 116 of phase-shifting plug. The volume of air trapped in compression chamber 130 is characterized by acoustic compliance proportional to the volume of compression chamber 130. In practice, the height of compression chamber 130 can be very small (e.g., about 0.5 mm or less), resulting in a small volume of compression chamber 130. According to the invention, the area above the surrounding area also becomes part of compression chamber 130. With this wider compression chamber 130, the resonance within compression chamber 130 will be shifted to a lower frequency, and the position of its node (zero point of pressure) will also change.

[0025] like Figures 1 to 6 As shown, the bottom portion 116 of the phasing plug 106 also includes at least one conduit 132 extending from the bottom surface 126 to the top surface 128 as a passage through the bottom portion 116, through which acoustic waves generated by the diaphragm 104 can travel. As depicted herein, a plurality of conduits 132 may be provided as concentric annular passages arranged circumferentially around a central axis 108, thereby forming concentric circles adjacent to the convex surface 124 of the diaphragm 104. The conduits 132 may be positioned at selected concentric radii to provide suppression of resonances (e.g., the first three resonances) in the compression chamber 130. In one or more embodiments, the conduits 132 may be positioned at the node of the highest resonance mode to be suppressed, while the remaining resonance modes may be suppressed by setting different areas or widths of the conduits 132. Since the surrounding material becomes part of the compression chamber 130, the conduits 132 may be offset toward the periphery of the bottom portion 116 of the phasing plug 106.

[0026] Actuation of diaphragm 104 generates a high-intensity sound pressure signal within compression chamber 130, and this signal travels as a sound wave through conduit 132 across the bottom portion 116 of phase-modulated plug 106. Conduit 132 is used to carry sound waves from all areas of the convex surface 124 of diaphragm 104 through the bottom portion 116 of phase-modulated plug. Each conduit 132 has a first end 134 adjacent to the convex surface 124 of diaphragm 104 and communicating with compression chamber 130, and a second end 136 at the top surface 128 of bottom portion 116. Conduits 132 may each have substantially similar lengths from their first end 134 to their second end 136, wherein the second ends 136 of conduits 132 converge to form an annular outlet 138 to compression actuator 100, such that each sound pulse exits the bottom portion 116 of phase-modulated plug as a coherent wavefront. The substantially similar lengths of conduits 132 eliminate high-frequency interference caused by the different propagation times of the signal from compression chamber 130 through conduits 132. In one or more embodiments, the catheter 132 may have different shapes so as to have substantially similar lengths from its first end 134 to its second end 136. For example, Figure 1 The central catheter 132 may alternatively have a curved shape so that its length is substantially similar to the length of the catheter 132 on either side. It should be understood that while three catheters 132 are shown herein, more or fewer catheters 132 are also fully contemplated.

[0027] In one or more embodiments, the top portion 118 of the phase-shifting plug 106 includes a plurality of radially extending channels 140 acoustically connected to an annular outlet 138. For example... Figures 1 to 3 and Figure 5 As shown, the top portion 118 may have a central segment 142 and a plurality of arms 144 extending outward therefrom, wherein a pair of adjacent arms 144 defines one of a plurality of radially expanding channels 140 therebetween. An outer edge 146 of the central segment 142 may be disposed inside the annular outlet 138, defining an aperture 148 between each pair of adjacent arms 144. In a top view, each arm 144 may have a thin-walled construction of substantially constant width, wherein this thin-walled spacing between the channels 140 ensures no contraction or narrowing as the signal exits the compression chamber 130. It should be understood, of course, that the phase-shifting plug 106 is not limited to the embodiments described herein, and that the bottom portion 116 and the top portion 118 may include other suitable shapes and configurations.

[0028] Therefore, the annular outlet 138 is joined and acoustically connected to a corresponding radially extended channel 140 defined between each pair of adjacent arms 144 and the bottom portion 116 of the phase-shifting plug 106. The channel 140 has an extended width and merges at the periphery 150 of the bottom portion 116, thus merging at the periphery of the compression driver 100. Actuation of the diaphragm 104 by the motor assembly 102 generates sound waves within the compression chamber 130, which travel through the annular outlet 138 and the radially extended channel 140 to produce a generally horizontal 360° radiation pattern of sound waves from the compression driver 100. The channel 140 can be used to ensure a uniform distribution of sound pressure around the entire compression driver 100 to achieve omnidirectional radiation of sound. In addition to the embodiments described herein, it is contemplated that the phase-shifting plug 106 may include fewer or more channels 140.

[0029] Figure 7 This is an exploded view of an omnidirectional loudspeaker 200 according to one or more embodiments, the omnidirectional loudspeaker including a compression driver 100 and an exponential horn including a first or lower horn member 202 and a second or upper horn member 204. The lower horn member 202 may be generally bowl-shaped, having a generally convex, upward-facing outer wall 206 and a generally concave, downward-facing inner wall 208 defining a lower cavity 210. Correspondingly, the upper horn member 204 may be generally bowl-shaped, having a generally convex, downward-facing outer wall 212 and a generally concave, upward-facing inner wall 214 defining an upper cavity 216. Both the upper horn member 204 and the lower horn member 202 may be rotationally symmetrical about a central axis 108.

[0030] At least one of the lower horn member 202 and the upper horn member 204 includes a recess 218, which may be generally cylindrical and sized to at least partially receive the compression driver 100. The recess 218 may be defined by a generally planar base plate member 220 and an upright wall structure 222 connected to and at least partially surrounding the base plate member, wherein the recess 218 includes an opening 224 adjacent to the outer walls 206, 212 of the corresponding horn members 202, 204. The compression driver 100 may be disposed or mounted within the recess 218, such as by engaging the floor member 220 with one or more fasteners to generate acoustic energy.

[0031] Figure 8This is a cross-sectional view of an omnidirectional loudspeaker 200 comprising a compression driver 100 and an upper horn member 202 and an upper horn member 204. With the compression driver 100 received in the lower horn member 202, the upper horn member 204 is mounted and secured to the compression driver 100 by fasteners such as mounting screws. Alternatively, if the compression driver 100 is received in the upper horn member 204, the lower horn member 202 can be secured to the compression driver 100. During assembly, the compression driver 100 is typically centered within the omnidirectional loudspeaker 200, and the lower horn member 202 and the upper horn member 204 may be spaced apart, for example, by the height of the top portion 118 of the phase-modulating plug 106. Sound waves generated by the diaphragm 104 propagate through a conduit 132 into a radially extending annular waveguide formed by a radially extending air passage 140 of the top portion 118 of the phase-modulating plug 106 and the outer walls 206, 212 of the lower horn member 202 and the upper horn member 204.

[0032] refer to Figure 1 The compression chamber 130 is located in the space between the diaphragm 104 and the bottom surface 126 of the phase-modulating plug bottom portion 116. In practice, the height of the compression chamber 130 can be very small (e.g., approximately 0.5 mm or less), resulting in a small volume. Actuation of the diaphragm 104 generates a high sound pressure level signal within the compression chamber 130, and this signal travels as a sound wave through the bottom surface 116 of the phase-modulating plug 106 via a conduit 132 that provides a passage from the bottom surface 126 to the top surface 128. With the conduit 132, the inlet area of ​​the phase-modulating plug 106 is significantly smaller than the area of ​​the diaphragm 104. The air path of the phase-modulating plug 106 essentially forms the starting point of the loudspeaker, used to control directivity (i.e., the coverage of sound pressure in a specific listening area) and increase the reproduced sound pressure level within a specific frequency range. The total acoustic cross-sectional area of ​​the air path, including the conduit 132 and the outward radiation channel 140, in the phase-tuning plug 106, as well as the total acoustic cross-sectional area of ​​the horn components 202 and 204, gradually increases to provide a smooth transition of sound waves. Sound waves radiate outward from the conduit 132 and the orifice 148 along the radially expanding channel 140, through the passage 226 between the compression driver 100 and the horn components 202 and 204, and propagate omnidirectionally into the surrounding environment.

[0033] The lower horn member 202 restricts the propagation of acoustic energy in a first axial direction (i.e., downward), while the upper horn member 204 restricts the propagation of acoustic energy in a second axial direction (i.e., upward). Therefore, the lower horn member 202 and the upper horn member 204 provide acoustic load for the compression driver 100 and control the directivity in the vertical plane. The lower horn member 202 and the upper horn member 204 are connected in a spaced-apart relationship along the central axis 108 via the compression driver 100, such that, in combination, the lower horn member 202 and the upper horn member 204 define a passage 226 therebetween to guide the flow of acoustic energy radially. Thus, the lower horn member 202 and the upper horn member 204 can function as radial horns, thereby providing omnidirectional coverage extending 360° around the central axis 108 to guide the flow of acoustic energy generated by the compression driver 100, thereby radiating horizontally outward 360° in all directions.

[0034] Of course, it should be understood that directional identifiers such as up, down, and upward and downward used herein are not restrictive, but simply used to provide an exemplary environment for the components of the omnidirectional loudspeaker 200 disclosed herein.

[0035] Figure 9 This is a cross-sectional view of an embodiment of an omnidirectional loudspeaker 200 including dual compression drivers 100. As shown, a first compression driver 100a is disposed within a lower horn member 202, while a second compression driver 100b is disposed within an upper horn member 204 with opposite axial orientations, wherein the first compression driver 100a and the second compression driver 100b can be fixed to each other. Thus, the first compression driver 100a generates sound in a first axial direction, while the second compression driver 100b generates sound in a second or opposite axial direction. The compression drivers 100a and 100b are vertically arranged in a very compact space within opposing recesses 218, and their outputs are mixed, wherein the drivers 100a and 100b can be directly fixed to each other, or both can be connected to an intermediate plate (not shown). This configuration also increases the sound pressure output and maximum sound pressure level of the omnidirectional loudspeaker 200, wherein the compression drivers 100a and 100b are vertically arranged in a very compact space within opposing recesses 218.

[0036] In another embodiment, compression drivers 100a and 100b of different sizes and frequency ranges can be used. For example, the high-frequency driver 100a can be disposed within the lower speaker member 202, while the mid-frequency driver 100b can be disposed within the upper speaker member 204. However, the omnidirectional loudspeaker 200 is not limited to this type and placement of drivers 100a and 100b. In such a configuration, two compression drivers 100a and 100b with different sized voice coils and diaphragms can be connected such that a summation of signals is provided at the output of the phase-shifting plug 106, and the outputs of the two drivers 100a and 100b pass through the passageway 226 formed between the speaker members 202 and 204, and then radiate uniformly in the horizontal plane, distributing the sound evenly in a 360° pattern. Thus, the omnidirectional loudspeaker 200 functions as a bidirectional system, thereby extending its frequency range.

[0037] Figure 10 An omnidirectional loudspeaker 200 is depicted, having a cover 228 enclosing a lower horn member 202 and an upper horn member 204. Each omnidirectional loudspeaker 200 is suitable as an independent acoustic unit; however, if a system with a higher sound pressure level output is desired, multiple omnidirectional loudspeakers 200 can be assembled modularly or stacked vertically, one on top of another, to form an omnidirectional loudspeaker array. The modularity of the omnidirectional loudspeaker 200 disclosed herein advantageously allows for the construction of loudspeaker systems with a wide range of potential strengths by assembling an appropriate number of loudspeaker units 200, each loudspeaker unit having the same size, mating and mounting surfaces, and fastening structure.

[0038] Figures 7 to 10 An axisymmetric horn 202, 204 with constant directivity (in the vertical plane) is shown, having a tapered extension at the beginning and a wider opening at the end to compensate for the "waist effect," which is the narrowing of the directional response of the tapered horn in its mid-range frequency band. Specifically, this effect is compensated by opening the flare of the horn 202, 204 at the beginning or end of the passageway 226. In an alternative embodiment, the horn 202, 204 may, for example, have an exponential profile or other profile, or may be asymmetrical in the vertical plane, oriented at a "downward and outward" angle, which may be more optimized for ceiling speakers.

[0039] The applications of the compression driver 100 and omnidirectional speaker 200 described herein include, but are not limited to, landscape sound systems, Hi-Fi systems, home lifestyle speaker systems, public address systems, alarm and warning sound systems, portable Bluetooth audio speakers, high-power suspended speakers, negative directional ceiling speakers, or other applications where omnidirectionality is desired or required. The use of the compression driver 100 in the omnidirectional speaker 200 disclosed herein advantageously results in increased efficiency compared to direct-radiating dome speakers. The compression driver 100 and omnidirectional speaker 200 provide uniform sound radiation at all frequencies throughout a 360° coverage area, are easily scalable for different sized voice coils and diaphragms, and provide a modular system for the construction of custom speaker arrays.

[0040] In the embodiments disclosed herein, a dome diaphragm provides a larger effective area than a ring diaphragm, increasing the maximum SPL output of the compression driver. Additionally, the dome diaphragm has a relatively low resonant frequency, and the combination of these characteristics makes the transducer well-suited for bidirectional linear arrays. Furthermore, the smaller cross-sectional size of the acoustic path improves directional control at high frequencies compared to drivers with circular exits.

[0041] While exemplary embodiments have been described above, they do not imply that these embodiments describe all possible forms of the invention. In fact, the wording used in this specification is descriptive rather than limiting, and it should be understood that various changes can be made without departing from the spirit and scope of the invention. Furthermore, features of various embodiments can be combined to form other embodiments of the invention.

Claims

1. A compression driver for an omnidirectional loudspeaker, the compression driver comprising: Motor assembly; A dome diaphragm, which is coaxially disposed above the motor assembly and operably connected to the motor assembly, the diaphragm having a convex surface and a concave surface; as well as A phase-modulating plug having a bottom portion and a top portion, the bottom portion having a concave bottom surface disposed adjacent to and defining a compression chamber therebetween the convex surface of the diaphragm, the phase-modulating plug including a plurality of conduits extending through the bottom portion for acoustic wave propagation, the plurality of conduits converging to form an annular outlet, and the top portion including a plurality of radially extending channels acoustically connected to the annular outlet. The actuation of the diaphragm by the motor assembly generates sound waves in the compression chamber, which travel through the annular outlet and the radially expanding channel to produce a horizontal 360° radiation pattern of sound waves from the compression driver; The top portion has a central segment and a plurality of arms extending outward therefrom, wherein a pair of adjacent arms defines one of the plurality of radially extending channels therebetween; The outer edge of the central segment is disposed inside the annular outlet, defining a hole between each pair of adjacent arms.

2. The compression actuator of claim 1, wherein the plurality of conduits comprises concentric annular passages.

3. The compression actuator of claim 1, wherein each of the plurality of conduits has a similar length from its first end to its second end.

4. The compression drive of claim 1, wherein each arm has a constant width.

5. The compression drive of claim 1, wherein the top portion has a constant height above the bottom portion.

6. An omnidirectional loudspeaker, the omnidirectional loudspeaker comprising: The lower horn component has a convex, upward-facing outer wall; An upper horn member, which is spaced apart from the lower horn member and has a convex, downward-facing outer wall; as well as At least one compression actuator connected along a central axis to one of the lower horn member or the upper horn member and comprising: a motor assembly; a dome diaphragm operably connected to the motor assembly and having a convex surface and a concave surface; a phase-shifting plug having a bottom portion and a top portion, the bottom portion having a concave bottom surface adjacent to the convex surface of the diaphragm and defining a compression chamber therebetween, wherein the phase-shifting plug includes a plurality of conduits extending through the bottom portion for acoustic wave propagation, the plurality of conduits converging to form an annular outlet; The lower horn member and the upper horn member are connected in a spaced-apart relationship along the central axis via the at least one compression driver to define a channel for radiating sound waves generated by the at least one compression driver in a horizontal 360° radiation pattern; The top portion has a central segment and a plurality of arms extending outward therefrom, wherein a pair of adjacent arms define one of the plurality of radially expanding channels therebetween; The outer edge of the central segment is disposed inside the annular outlet, defining a hole between each pair of adjacent arms.

7. The omnidirectional loudspeaker of claim 6, wherein the plurality of conduits comprises concentric annular pathways.

8. The omnidirectional loudspeaker of claim 6, wherein each of the plurality of conduits has a similar length from its first end to its second end.

9. The omnidirectional loudspeaker of claim 6, wherein the top portion includes a plurality of radially extending channels acoustically connected to the annular outlet, wherein sound waves are generated in the compression chamber by actuation of the diaphragm by the motor assembly, the sound waves traveling through the annular outlet and the radially extending channels.

10. The omnidirectional loudspeaker of claim 6, wherein each arm has a constant width.

11. The omnidirectional loudspeaker of claim 6, wherein the top portion has a constant height above the bottom portion.

12. The omnidirectional loudspeaker of claim 6, wherein at least one of the lower horn member or the upper horn member includes a recess for at least partially receiving the at least one compression driver.

13. The omnidirectional loudspeaker of claim 6, wherein the lower horn member includes a concave, downward-facing inner wall defining a lower cavity, and wherein the upper horn member includes a concave, upward-facing inner wall defining an upper cavity.

14. The omnidirectional loudspeaker of claim 6, wherein the at least one compression driver comprises a first compression driver disposed in the lower horn member and a second compression driver disposed in the upper horn member with opposite axial orientations.

15. An omnidirectional loudspeaker, the omnidirectional loudspeaker comprising: The lower horn component has a convex, upward-facing outer wall; An upper horn member, which is spaced apart from the lower horn member and has a convex, downward-facing outer wall; as well as A compression driver, the compression driver being connected along a central axis to one of the lower horn member or the upper horn member and comprising... Motor assembly, A dome-shaped diaphragm, operably connected to the motor assembly and having convex and concave surfaces, and A phase-modulating plug has a bottom portion and a top portion, the bottom portion having a concave bottom surface adjacent to and defining a compression chamber therebetween the convex surface of the diaphragm. The phase-modulating plug includes a plurality of conduits extending through the bottom portion for acoustic wave propagation, the plurality of conduits converging to form an annular outlet. The top portion includes a plurality of radially extending channels acoustically connected to the annular outlet, wherein acoustic waves are generated in the compression chamber by actuation of the diaphragm by the motor assembly, the acoustic waves traveling through the annular outlet and the radially extending channels. The lower horn member and the upper horn member are connected in a spaced-apart relationship along the central axis via the compression driver to define a channel for radiating sound waves generated by the compression driver in a horizontal 360° radiation pattern; The top portion has a central segment and a plurality of arms extending outward therefrom, wherein a pair of adjacent arms define one of the plurality of radially expanding channels therebetween; The outer edge of the central segment is disposed inside the annular outlet, defining a hole between each pair of adjacent arms.

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