Compound multi-frequency diffuser reflector
By using a composite multi-frequency diffusion reflector structure, the problems of weak high-frequency diffusion, insufficient sound quality, and monotonous appearance are solved, achieving high-frequency sound energy diffusion effect and sound quality improvement, thus enhancing stage sound effects and aesthetics.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- SHENZHEN TONGSHENG TECHNOLOGY CO LTD
- Filing Date
- 2025-06-17
- Publication Date
- 2026-07-14
AI Technical Summary
Existing acoustic reflectors have weak high-frequency diffusion capabilities, resulting in a less warm sound quality, a monotonous appearance, and a lack of aesthetic appeal.
The structure adopts a composite multi-frequency diffusion acoustic shield, including an acoustic reflector, a diffusion group, and a polymer surface layer. The acoustic reflector consists of a mid-to-high frequency acoustic reflector layer, a high-density sound insulation layer wrapped inside, and a honeycomb core layer. The diffusion group is composed of a diamond-shaped geometric diffuser. By combining multiple layers of materials with aluminum honeycomb panels and damping sound insulation felt, the absorption of low-frequency sound energy is reduced to improve the high-frequency diffusion effect.
It improves the high-frequency sound energy diffusion capability, enhances the warmth and overall aesthetics of the sound quality, and improves the uniformity of the sound field.
Smart Images
Figure CN224501484U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of sheet metal technology, and in particular to a composite multi-frequency diffusion acoustic shield. Background Technology
[0002] As cultural life becomes increasingly richer, people have higher demands for stage effects in performances. When holding concerts in theaters, the vast stage space diffuses and absorbs most of the musical energy. During acoustic performances and singing, the audience receives only a weak amount of music power, resulting in a poor sound effect. To achieve ideal sound quality and sound pressure levels in the audience area, a sound reflector is needed. It extends reverberation time, enhances timbre, and strengthens the performance, allowing the audience to appreciate beautiful sounds.
[0003] Key technologies for acoustic shields include structural and material technologies. Structurally, there are suspended and liftable designs. Suspended designs utilize steel cables and trusses for raising and lowering, while liftable designs can adjust the height to meet different needs. In terms of materials, development has shifted from high-density fiberboard.
[0004] Common acoustic reflectors have a good diffusion effect on mid and low frequencies, but a weak diffusion ability on high frequencies, resulting in a less warm sound quality, a monotonous appearance, and a lack of aesthetic appeal. Utility Model Content
[0005] In view of the above problems, this utility model proposes an embodiment to provide a composite multi-frequency diffusion acoustic shield that overcomes or at least partially solves the above problems:
[0006] A composite multi-frequency diffusion acoustic shield includes an acoustic reflector, a diffusion assembly, and a polymer surface layer.
[0007] The sound reflector is arc-shaped, with the diffusion group disposed on the concave surface of the sound reflector, and the polymer surface layer disposed on the convex surface and both sides of the sound reflector; wherein the concave surface and the convex surface are disposed opposite to each other;
[0008] The sound reflector includes a mid-to-high frequency sound reflector layer, as well as a high-density sound insulation layer, a mid-to-low frequency sound reflector layer, and a honeycomb core layer wrapped inside the mid-to-high frequency sound reflector layer.
[0009] The diffusion group comprises at least two diamond-shaped geometric diffusers.
[0010] Preferably, the diamond-shaped geometric diffuser includes a diamond-shaped high-frequency diffuser, a pin, and a connecting post;
[0011] The pin is provided on the side of the diamond-shaped high-frequency diffuser that is connected to the reflector plate, and the pin is provided with the connecting post; the connecting post and the pin are arranged perpendicularly.
[0012] Preferably, the diffusion group consists of at least two different sizes of diamond-shaped geometric diffusers.
[0013] Preferably, the low-to-medium frequency reflective layer encapsulates the honeycomb core layer;
[0014] The high-density sound insulation layer is disposed on the concave surface of the low-to-mid frequency sound-reflecting layer and the high-to-mid frequency sound-reflecting layer.
[0015] Preferably, the high-density sound insulation layer is a damping sound insulation felt.
[0016] Preferably, the honeycomb core layer is an aluminum honeycomb core.
[0017] Preferably, the polymer surface layer is a polyvinyl chloride resin layer.
[0018] Preferably, the high-density sound insulation layer is connected to the mid-to-high frequency sound reflector and the mid-to-low frequency sound reflector respectively by adhesive.
[0019] Preferably, the thickness of the reflector plate is in the range of 15-80mm.
[0020] Preferably, the thickness of the reflector plate is 40 mm.
[0021] This application specifically includes the following advantages:
[0022] In the embodiments of this application, compared with the problems of weak high-frequency diffusion, insufficient sound warmth, monotonous appearance, and lack of aesthetic appeal in the prior art, this application provides a solution that improves the warmth of the sound quality by reducing the absorption of low-frequency sound energy while increasing the density of the board material. A solution is achieved by connecting the diamond-shaped high-frequency diffuser to the board material via pins, thereby improving the diffusion of high-frequency sound energy. Specifically, it includes a sound reflector, a diffusion group, and a polymer surface layer; the sound reflector is arc-shaped, the diffusion group is disposed on the convex surface of the sound reflector, and the polymer surface layer is disposed on the convex surface and both sides of the sound reflector; wherein the concave surface is disposed opposite to the convex surface; the sound reflector includes a mid-high frequency sound reflector layer, and a high-density sound insulation layer, a mid-low frequency sound reflector layer, and a honeycomb core layer wrapped inside the mid-high frequency sound reflector layer; the diffusion group includes at least two diamond-shaped geometric diffusers. The composite multi-frequency diffuser acoustic enclosure structure addresses the issues of weak high-frequency diffusion, insufficient sound warmth, monotonous appearance, and lack of aesthetic appeal by employing a reflector and a diamond-shaped geometric diffuser. In this application, multiple layers of sheet metal are bonded together with aluminum honeycomb panels and damping sound insulation felt using adhesive. This reduces the absorption of low-frequency sound energy without significantly increasing the density of the sheet metal, thereby improving the warmth of the sound quality. The diamond-shaped geometric diffuser is connected to the sheet metal via pins, further enhancing the diffusion of high-frequency sound energy, improving sound field uniformity, and enhancing the overall aesthetics of the acoustic enclosure. Attached Figure Description
[0023] To more clearly illustrate the technical solution of this application, the drawings used in the description of this application will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0024] Figure 1 This is an enlarged structural schematic diagram of a composite multi-frequency diffusion acoustic shield according to this utility model;
[0025] Figure 2 This is a schematic diagram of the overall structure of a composite multi-frequency diffusion acoustic shield according to this utility model;
[0026] Figure 3 This is a schematic diagram of the diffusion group structure of a composite multi-frequency diffusion acoustic shield according to this utility model;
[0027] Figure 4 This is a schematic diagram of the main structure of the first diamond-shaped geometric diffuser of a composite multi-frequency diffusion acoustic shield according to this utility model.
[0028] Figure 5 This is a side view of the first diamond-shaped geometric diffuser of a composite multi-frequency diffusion acoustic shield according to this utility model.
[0029] Figure 6 This is a side view of the first diamond-shaped geometric diffuser of a composite multi-frequency diffusion acoustic shield according to this utility model.
[0030] 1. Honeycomb core layer; 2. Mid-to-low frequency sound-reflecting layer; 3. High-density sound insulation layer; 4. Mid-to-high frequency sound-reflecting layer; 5. Polymer surface layer; 6. Diffusion group; 61. First diamond-shaped geometric diffuser; 62. Second diamond-shaped geometric diffuser; 63. Third diamond-shaped geometric diffuser; 64. Fourth diamond-shaped geometric diffuser. Detailed Implementation
[0031] To make the objectives, features, and advantages of this application more apparent and understandable, the application will be further described in detail below with reference to the accompanying drawings and specific embodiments. Obviously, the described embodiments are only some, not all, of the embodiments of this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.
[0032] The inventors, through analysis of existing technologies, discovered that as cultural life becomes increasingly richer, people's demands for stage effects in performances are also rising. When holding concerts in theaters, the vast stage space diffuses and absorbs most of the musical energy; during acoustic performances, the audience receives only weak musical power, resulting in a poor musical effect. To achieve ideal sound effects and sound pressure levels in the audience area, a sound reflector is needed. It can extend reverberation time, enhance timbre, and strengthen the performance effect, allowing the audience to appreciate beautiful sounds.
[0033] Key technologies for acoustic reflectors include structural and material technologies. Structurally, there are suspended and height-adjustable designs. Suspended designs utilize steel cables and trusses for raising and lowering, while height-adjustable designs allow for height adjustment to suit different needs. In terms of materials, the technology has evolved from high-density fiberboard to aluminum honeycomb panels. The latter is lightweight, high-strength, and has good flatness, effectively reflecting sound. However, its low density leads to excessive absorption of low frequencies, resulting in a lack of warmth in the sound quality. Furthermore, most common acoustic reflector shapes employ large, curved designs. While this shape provides good diffusion for mid- and low-frequency frequencies, it is weak in high-frequency diffusion. Therefore, the key point of this patent is to address these two weaknesses of conventional acoustic reflectors through innovative designs in materials and shape. By combining multi-layered panels with aluminum honeycomb panels and damping sound insulation felt, the absorption of low-frequency sound energy is reduced without significantly increasing the density of the panels, thereby improving the warmth of the sound quality. By adding small diamond-shaped geometric diffusers to the large curved panels, the effect of high-frequency sound energy diffusion is improved, the uniformity of the sound field is enhanced, and the overall aesthetics of the acoustic reflector are improved.
[0034] Reference Figures 1-6 This diagram illustrates a structural schematic of a composite multi-frequency diffusion acoustic reflector according to the present invention. Specifically, it may include the following structure: an acoustic reflector plate, a diffusion group 6, and a polymer surface layer 5; the acoustic reflector plate is arc-shaped, the diffusion group 6 is disposed on the convex surface of the acoustic reflector plate, and the polymer surface layer 5 is disposed on both the convex surface and both sides of the acoustic reflector plate; wherein the concave surface is disposed opposite to the convex surface; the acoustic reflector plate includes a mid-to-high frequency acoustic reflector layer 4, and a high-density sound insulation layer 3, a mid-to-low frequency acoustic reflector layer 2, and a honeycomb core layer 1 encased within the mid-to-high frequency acoustic reflector layer 4; the diffusion group 6 includes at least two diamond-shaped geometric diffusers. Figure 6 As shown, multiple reflectors are equipped with diffusion groups 6, forming a composite multi-frequency diffusion reflector.
[0035] The following will further describe a composite multi-frequency diffusion acoustic shield in this exemplary embodiment.
[0036] In one embodiment of this application, a composite multi-frequency diffusion acoustic shield includes an acoustic reflector, a diffusion group 6, and a polymer surface layer 5; the acoustic reflector is arc-shaped, the diffusion group 6 is disposed on the convex surface of the acoustic reflector, and the polymer surface layer 5 is disposed on the convex surface and both sides of the acoustic reflector; wherein, the concave surface is disposed opposite to the convex surface; the mid-low frequency acoustic reflector layer 2 wraps the honeycomb core layer 1; the high-density sound insulation layer 3 is disposed on the concave surface of the mid-low frequency acoustic reflector layer 2 and the mid-high frequency acoustic reflector layer 4.
[0037] In one specific embodiment, the composite multi-frequency diffusion acoustic reflector of this application adopts a multi-layer composite structure design. The core is composed of an arc-shaped acoustic reflector plate, whose concave surface integrates a diffusion group 6 to achieve multi-directional scattering of sound waves. The convex surface and both sides are covered with a polymer surface layer 5 to form a gradually changing acoustic impedance interface. The internal structure of the acoustic reflector plate uses a honeycomb core layer 1 as a supporting skeleton, and is surrounded by a mid-to-low frequency acoustic reflector layer 2 to reflect sound energy in the 100-500Hz frequency band. The honeycomb structure combines lightweight and rigidity.
[0038] In one specific embodiment, the high-density sound insulation layer 3 is tightly bonded between the concave surfaces of the low-to-mid frequency reflective layer 2 and the mid-to-high frequency reflective layer 4, blocking the transmission of mid-to-high frequency sound waves in the 500-2000Hz range through the mass law effect. The diffusion group 6 consists of periodically arranged diffusers with varying depth gradients to cover the 250-5kHz frequency band. The polymer surface layer 5 is a polyurethane-rubber composite material with an acoustic impedance between that of air and the reflective plate, achieving a broadband progressive conversion of sound energy. The overall structure achieves sound wave phase interference cancellation through an arc shape, with a diffusion coefficient of 0.92.
[0039] In one embodiment of this application, the honeycomb core layer 1 is an aluminum honeycomb core. The aluminum honeycomb core layer 1 is made of aluminum alloy with a regular hexagonal honeycomb structure, which can have a side length of 5mm and a wall thickness of 0.05mm, possessing both high specific stiffness and excellent acoustic performance. Its honeycomb cavity can induce the Helmholtz resonance effect, effectively absorbing mid-to-low frequency sound waves, while attenuating vibration transmission through structural damping.
[0040] As an example, the honeycomb core layer 1 is located in the middle and is arc-shaped, with a low-to-mid frequency reflective layer 2 wrapped around it.
[0041] In one specific embodiment, the aluminum honeycomb core layer 1 serves as the core support structure, employing an arc-shaped design with the same curvature as the acoustic reflector to precisely conform to the overall acoustic surface. Its aluminum alloy hexagonal honeycomb units are oriented along the arc's normal direction and undergo anodizing treatment to enhance damping performance. The honeycomb core layer 1 is conformally bonded to the outer mid-low frequency acoustic reflector layer 2 using epoxy resin structural adhesive. The mid-low frequency acoustic reflector layer 2 can be a EPDM rubber-based composite material. The anisotropic design of the honeycomb structure achieves a radial stiffness of 120 MPa while retaining 15% tangential flexibility to suppress standing wave formation.
[0042] In one embodiment of this application, the high-density sound insulation layer 3 is a damping sound insulation felt. The high-density sound insulation layer 3 is connected to the mid-high frequency sound reflector and the mid-low frequency sound reflector respectively by adhesive. The high-density sound insulation layer 3 is disposed on the concave surface of the mid-low frequency sound reflector 2 and the mid-high frequency sound reflector 4.
[0043] As an example, the high-density sound insulation layer 3 is only set on the convex surface and not on other surfaces, and the mid-low frequency sound reflection layer 2 is a frame-shaped enclosure of the honeycomb core layer 1.
[0044] In one specific embodiment, the high-density sound insulation layer 3 can be made of lead-rubber composite material and is tightly bonded to the mid-high frequency and mid-low frequency sound reflectors respectively using high-strength polyurethane adhesive. This sound insulation layer is only installed on the convex surface of the sound reflectors; the concave surfaces and sides are not covered, thus achieving directional acoustic control. The mid-low frequency sound reflector 2 adopts a frame structure, forming a broadband sound reflector structure. This frame completely encloses the internal aluminum honeycomb core layer 1 through a dual fixing method of mechanical clips and structural adhesive, ensuring overall structural rigidity. The connection surface between the high-density sound insulation layer 3 and the mid-high frequency sound reflector is sandblasted to enhance adhesion. Simultaneously, a 0.5 mm thick buffer transition layer is provided on the side of the mid-low frequency sound reflector 2 to avoid abrupt changes in acoustic impedance. This layered design allows low-frequency sound waves to be absorbed first by the honeycomb core layer 1 and the mid-low frequency sound reflector 2, the remaining mid-high frequency components are then blocked by the high-density sound insulation layer 3, and finally, the sound energy is dissipated through the concave diffusion group 6, forming a stepped noise reduction mechanism.
[0045] In one embodiment of this application, the sound reflector includes a mid-to-high frequency sound reflector layer 4, and a high-density sound insulation layer 3, a mid-to-low frequency sound reflector layer 2, and a honeycomb core layer 1 encased within the mid-to-high frequency sound reflector layer 4. The mid-to-high frequency sound reflector layer 4 is frame-shaped.
[0046] In one specific embodiment, the mid-to-high frequency sound-reflecting layer 4 adopts a frame structure and can be made of high-rigidity glass fiber reinforced resin. This frame directly wraps the high-density sound insulation layer 3 and the mid-to-low frequency sound-reflecting layer 2, and the overall structure takes into account both mid-to-high frequency sound absorption and mechanical support functions.
[0047] In one embodiment of this application, the convex surface and both sides of the acoustic reflector are provided with the polymer surface layer 5; the polymer surface layer 5 is a polyvinyl chloride resin layer (PVC layer). The thickness of the acoustic reflector is in the range of 15-80mm, and can be any thickness between 15-80mm, such as 15mm, 20mm, 25mm, 30mm, 35mm, 45mm, 50mm, 60mm, 70mm, 80mm, etc. In this application, the thickness of the acoustic reflector is 40mm.
[0048] In one embodiment of this application, the convex surface and both sides of the acoustic reflector are covered with a polyvinyl chloride resin layer, which has excellent weather resistance and acoustic impedance matching characteristics. The total thickness of the acoustic reflector is designed to be 40mm, and from the inside out, it consists of: an aluminum honeycomb core layer 1, a mid-to-low frequency acoustic reflector layer 2, a high-density sound insulation layer 3, and a mid-to-high frequency acoustic reflector frame. The PVC surface layer is composited with the acoustic reflector substrate using a hot-pressing process, and the surface is frosted to optimize sound wave scattering performance. This thickness design achieves optimal acoustic performance while ensuring structural strength.
[0049] In one embodiment of this application, the diffusion group 6 includes at least two diamond-shaped geometric diffusers; each diamond-shaped geometric diffuser includes a diamond-shaped high-frequency diffuser, a pin, and a connecting post; the pin is disposed on the side of the diamond-shaped high-frequency diffuser connected to the reflector, and the connecting post is disposed on the pin; the connecting post and the pin are perpendicularly arranged. The diffusion group 6 is composed of at least two different sizes of diamond-shaped geometric diffusers.
[0050] As an example, the diffuser assembly 6 consists of a diamond-shaped high-frequency diffuser array, containing diffuser units of two different sizes arranged in a staggered pattern. Each diamond-shaped high-frequency diffuser is CNC machined from aerospace-grade aluminum, with cylindrical pins on its facets facing away from the sound field, the pin axis perpendicular to the diffuser surface. Connecting posts of different sizes create a stepped, three-dimensional layout of diffusers of varying sizes. The diffuser surfaces are anodized, and the edges are chamfered, achieving a diffusion coefficient as high as 0.95 in the 2500-8000Hz frequency range. The pins and connecting posts use a transition fit to ensure installation accuracy, and the entire diffuser assembly 6 features a detachable structure for modular maintenance.
[0051] In one specific embodiment, the diamond-shaped geometric diffuser includes four different models: the first diamond-shaped geometric diffuser 61 with a main diagonal of 85mm, the second diamond-shaped geometric diffuser 62 with a main diagonal of 68mm, the third diamond-shaped geometric diffuser 63 with a main diagonal of 57mm, and the fourth diamond-shaped geometric diffuser 61 with a main diagonal of 49mm.
[0052] In one specific embodiment, the first row features a fourth diamond-shaped geometric diffuser 61. The second row is 190mm apart from the first row. The second row features a third diamond-shaped geometric diffuser 63 and two fourth diamond-shaped geometric diffusers 61, with the fourth diamond-shaped geometric diffusers 61 positioned on either side of the third diamond-shaped geometric diffuser 63. The third diamond-shaped geometric diffusers 63 in the second row are coaxial with the fourth diamond-shaped geometric diffusers 61 in the first row. The third row features a second diamond-shaped geometric diffuser 62 at its center, with a third diamond-shaped geometric diffuser 63 and a fourth diamond-shaped geometric diffuser 61 on each side. The fourth row features a first diamond-shaped geometric diffuser 61 at its center, with a second diamond-shaped geometric diffuser 62, a third diamond-shaped geometric diffuser 63, and a fourth diamond-shaped geometric diffuser 61 on each side. The overall shape is triangular and aesthetically pleasing. The distance between the second and third rows is 160mm, and the distance between the third and fourth rows is 130mm.
[0053] In one specific embodiment, the diffuser group 6 adopts a progressive layout of four-stage diamond-shaped geometric diffusers to achieve precise acoustic phase control. The first row features a single 49mm diffuser as the apex, expanding downwards layer by layer: the second row has a 57mm main body that, together with the 49mm units on both sides, forms the basic scattering surface; the third row has a 68mm central body that, together with the 57mm and 49mm units, constitutes the mid-frequency diffusion region; and the fourth row has an 85mm core diffuser that, in conjunction with secondary units, completes broadband coverage. The row spacing decreases in gradients of 190mm, 160mm, and 130mm, ensuring that the diffuser projected area ratio strictly follows a 1:1.25:1.5:2 acoustic wavelength matching relationship. The main diagonal length of each diffuser corresponds to different characteristic frequencies, and coaxial arrangement ensures uniform diffusion of acoustic energy in the vertical direction. The triangular array maintains a diffusion efficiency of over 0.9 in the 8000Hz frequency band.
[0054] Although preferred embodiments of the present invention have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of the present invention.
[0055] Finally, it should be noted that in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or terminal device that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or terminal device. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or terminal device that includes said element.
[0056] The above provides a detailed description of the composite multi-frequency diffusion acoustic shield provided by this utility model. Specific examples have been used to illustrate the principle and implementation of this utility model. The description of the above embodiments is only for the purpose of helping to understand the method and core idea of this utility model. At the same time, for those skilled in the art, there will be changes in the specific implementation and application scope based on the idea of this utility model. Therefore, the content of this specification should not be construed as a limitation of this utility model.
Claims
1. A composite multi-frequency diffusion acoustic shield, characterized in that, Includes a reflector, a diffuser assembly, and a polymer surface layer; The sound reflector is arc-shaped, and the diffusion group is arranged on the convex surface of the sound reflector. The polymer surface layer is arranged on the convex surface and both sides of the sound reflector. The concave surface of the sound reflector is arranged opposite to the convex surface. The sound reflector includes a mid-to-high frequency sound reflector layer, as well as a high-density sound insulation layer, a mid-to-low frequency sound reflector layer, and a honeycomb core layer wrapped inside the mid-to-high frequency sound reflector layer. The diffusion group comprises at least two diamond-shaped geometric diffusers.
2. The composite multi-frequency diffusion acoustic shield according to claim 1, characterized in that, The diamond-shaped geometric diffuser includes a diamond-shaped high-frequency diffuser, a pin, and a connecting post; The pin is provided on the side of the diamond-shaped high-frequency diffuser that is connected to the reflector plate, and the pin is provided with the connecting post; the connecting post and the pin are arranged perpendicularly.
3. The composite multi-frequency diffusion acoustic shield according to claim 1, characterized in that, The diffusion group consists of at least two different sizes of diamond-shaped geometric diffusers.
4. The composite multi-frequency diffusion acoustic shield according to claim 1, characterized in that, The low- and mid-frequency acoustic reflective layer encapsulates the honeycomb core layer; The high-density sound insulation layer is disposed on the concave surface of the low-to-mid frequency sound-reflecting layer and the high-to-mid frequency sound-reflecting layer.
5. The composite multi-frequency diffusion acoustic shield according to claim 1, characterized in that, The high-density sound insulation layer is a damping sound insulation felt.
6. The composite multi-frequency diffusion acoustic shield according to claim 1, characterized in that, The honeycomb core layer is an aluminum honeycomb core.
7. The composite multi-frequency diffusion acoustic shield according to claim 1, characterized in that, The polymer surface layer is a polyvinyl chloride resin layer.
8. The composite multi-frequency diffusion acoustic shield according to claim 1, characterized in that, The high-density sound insulation layer is connected to the mid-to-high frequency sound reflection layer and the mid-to-low frequency sound reflection layer by adhesive.
9. The composite multi-frequency diffusion acoustic shield according to claim 1, characterized in that, The thickness of the reflector plate ranges from 15 to 80 mm.
10. The composite multi-frequency diffusion acoustic shield according to claim 9, characterized in that, The thickness of the reflector plate is 40mm.