CN111951749A - Soundboard with sound beam and sound tunnel in an upright piano - Google Patents

Abstract

A soundboard with a sound beam and a sound tunnel in an upright piano, the outer wall of the soundboard is provided with a first groove and a second groove, the first groove is arranged laterally in the length direction of the soundboard, and the second groove is arranged in the width of the soundboard The two grooves are crossed and penetrate each other, dividing the outer wall of the soundboard into four resonance areas equally; the center of the outer wall of the soundboard is also provided with a sound beam assembly, including a plurality of strip-shaped sound-beam members. They are arranged in pairs on both sides of the first groove and on both sides of the second groove; the first groove forms a transverse sound tunnel on the outer wall of the soundboard, and the second groove forms a longitudinal sound tunnel on the outer wall of the soundboard. The invention changes the soundboard from the previous free vibration mode to the current standard vibration mode, and solves the problem that the high-pitched area of the upright piano cannot be bright and the low-pitched area is not rich and round enough from the perspective of vibration, resonance and sound production, especially for the bass. Area pronunciation has been improved. Practice has proved that the improved design scheme has outstanding substantive features and significant technological progress.

Description

Soundboard with sound beam and sound tunnel in an upright piano

technical field

The invention relates to an upright piano, in particular to a soundboard with a sound beam and a sound tunnel in an upright piano.

Background technique

The piano is a keyboard instrument in Western classical music, and is known as the "king of musical instruments". Consists of 88 keys (52 white keys, 36 black keys) and metal soundboard.

The piano has a total of six main structures, including strings, iron row skeleton, soundboard, action system, wooden shell, and pedals. The soundboard (see Figure 1) is composed of a resonance board (also known as a large soundboard), a support wood (also known as a gear), a soundboard frame and a chord code. The resonant plate is like a thin plate, with the help woods arranged at a certain distance below it, and the soundboard frame is pasted around it, and the middle and high-pitched strings and the bass strings are fixed on it. When the strings vibrate, through the transmission of the strings attached to the soundboard, the soundboard vibrates and the soundboard starts to work. The soundboard is one of the components that plays an important role in the sound quality of the piano. After the strings are struck by the hammers, they vibrate and produce sound. Through the transmission of the string code, the soundboard is subjected to the vibration from the strings to enhance the sound radiation, strengthen its original sound, and maximize the energy it obtains from the vibrating strings as much as possible. broadcast in the air.

The sound range of a piano is usually seven octaves, of which the upper range occupies about half an octave, the middle range occupies about four octaves, and the low range occupies about two and a half octaves.

The common problem of traditional upright pianos is that when the upright piano is sounding, its soundboard has a natural resonance frequency. After a certain range of the resonance frequency region, the high-pitched area cannot be bright, and the low-pitched area is not rich and round enough. In particular, the sound quality in the bass region has always been a shortcoming of the piano, even limiting the composer's creative width. The main reason is that the soundboard of the current upright piano cannot satisfy the good broadband vibration from the treble region to the bass region, that is, it cannot simultaneously adapt to the resonance and vibration of the wide frequency changes in the treble region, the mid-range region and the bass region. To sum up, the structural design of the soundboard of the traditional upright piano is unreasonable, which is not conducive to the soundboard to exert good sound wave vibration from the treble region to the bass region.

Therefore, how to solve the above-mentioned deficiencies in the prior art becomes the subject to be solved by the present invention.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide a soundboard with a sound beam and a sound tunnel in an upright piano.

To achieve the above object, the technical scheme adopted in the present invention is:

A soundboard with a sound beam and a sound tunnel in an upright piano, the soundboard is rectangular, and its inner wall is arranged toward the strings of the piano;

The outer wall of the soundboard is provided with a first groove and a second groove, wherein the first groove is arranged transversely in the length direction of the soundboard, and the second groove is arranged longitudinally in the width direction of the soundboard;

The first groove and the second groove are crossed on the outer wall of the soundboard and pass through each other, the intersection is located in the center of the soundboard, and then the outer wall of the soundboard is equally divided into four resonance areas;

A sound beam assembly is also provided in the center of the outer wall of the soundboard, and the sound beam assembly includes a plurality of strip-shaped sound beam members, and the strip-shaped sound beam members are arranged in pairs on both sides of the first groove and the second groove. both sides of the slot;

The first groove forms a transverse sound tunnel on the outer wall of the soundboard, and the second groove forms a longitudinal sound tunnel on the outer wall of the soundboard.

The relevant contents in the above technical solutions are explained as follows:

1. In the above solution, the first groove and the second groove are crossed on the outer wall of the soundboard and pass through each other, which helps to quickly pass the vibration of the strings through the cross-shaped sound tunnel (that is, the sound tunnel) formed by the groove. Pass around the soundboard.

2. In the above solution, the intersection of the first groove and the second groove is located at the center of the soundboard, so as to improve the sound quality and timbre of the soundboard.

3. In the above solution, a connecting beam is arranged between two adjacent sound beam members, and the connecting beam spans the top of the first groove and the second groove, forming the sound beam assembly. and each of the connecting beams is located in the central area of the surface of the soundboard. With this design, the central area of the soundboard can be reinforced.

4. In the above solution, a plurality of radiating sound beams are respectively provided in each of the resonant regions of the soundboard, each radiating sound beam in the same resonance region is arranged in parallel, and one end of at least one of the radiating sound beams faces the soundboard horizontally. The geometric center of the direction, thereby enhancing the strength of the soundboard.

5. In the above solution, the soundboard is further provided with a plurality of radiating sound beams, the radiating sound beams are located in each of the resonance regions and are radially arranged with the center of the soundboard in the horizontal direction as a reference.

6. In the above scheme, the soundboard is divided into a peripheral high-pitched region, a mid-range mid-range and a central low-pitched region from the sound frequency band; wherein, the soundboard wall thickness gradually increases from outside to inside, forming the wall thickness of the low-pitched region. The wall thickness of the mid-range is greater than the wall thickness of the mid-range, and the sound beam assembly is located in the low-frequency range.

With this design, by arranging the thicker bass region near the center, the low-frequency vibration with lower frequency and larger amplitude can produce a richer and more rounded bass in the bass region of the soundboard; The treble area is set away from the center, which can make the high-frequency vibration with higher frequency and smaller amplitude emit a more transparent and bright treble in the treble area of the soundboard, thereby making the upright piano in the whole frequency range. The sound quality has been effectively improved.

7. In the above solution, the strip-shaped sound beam member is composed of a wooden base and a weighted block connected to the wooden base. With this design, the central area of the soundboard can be reinforced, which has a positive effect on improving the tone and sound quality of the bass region.

8. In the above solution, the thickness of the inner end of the strip-shaped sound beam member is greater than that of the outer end, and the thickness of the inner end of the radiating sound beam is greater than the thickness of the outer end. By this design, the central region of the soundboard can be strengthened.

9. In the above solution, both the first groove and the second groove are arc-shaped grooves, which can minimize the sudden change in thickness of the soundboard and avoid affecting the resonance and vibration of the soundboard.

10. In the above solution, the lengths of the first groove and the second groove are both smaller than the horizontal width of the soundboard, and the outer ends of the first groove and the second groove are connected to the outer wall of the soundboard. There are smooth transition surfaces in between.

The working principle and advantages of the present invention are as follows:

The present invention is a soundboard with a sound beam and a sound tunnel in an upright piano. The outer wall of the soundboard is provided with a first groove and a second groove, the first groove is arranged laterally in the length direction of the soundboard, and the second groove The board is arranged longitudinally in the width direction; the two grooves are crossed and pass through each other, dividing the outer wall of the soundboard into four resonance areas equally; the center of the outer wall of the soundboard is also provided with a sound beam assembly, including a plurality of strip-shaped sound beam components. The beam members are arranged in pairs on both sides of the first groove and on both sides of the second groove; the first groove forms a transverse sound tunnel on the outer wall of the sound board, and the second groove forms a longitudinal sound tunnel on the outer wall of the sound board.

Compared with the prior art, in order to solve the problem that the existing upright pianos cannot take into account the high, middle and low frequency regions and have good resonant timbre, the present invention designs the soundboards in the existing upright pianos, especially the upright pianos. Improvements have been made. It is embodied in the following aspects: first, a sound beam assembly is erected on the outer wall of the sound board; second, a cross-shaped groove is opened on the outer wall of the sound board, thereby forming a cross-shaped sound tunnel on the outer wall of the sound board.

Aiming at the problem that the high-pitched area of the existing upright piano cannot be bright, and the low-pitched area is not rich and round enough, the present invention conducts an in-depth discussion and research on the design and sound production mechanism of the upright piano, and finds out the high-pitched area and the sound-producing mechanism of the existing upright piano. The main reason for the poor sound in the low range is due to the unreasonable soundboard design. Accordingly, the inventor broke the shackles of the previous upright piano composition design, and boldly proposed an improved design scheme of the present invention. This improved design scheme changes the soundboard from the previous free vibration mode to the current standard vibration mode, from vibration The angle of resonance and sound production solves the problem that the high-pitched area of the upright piano is not bright, and the low-pitched area is not rich and round enough. Practice has proved that the improved design scheme has outstanding substantive characteristics and significant technical progress, and has obtained obvious technical Effect.

In particular, the invention improves the soundboard in view of the relatively prominent sound quality problem in the low-frequency range of the existing upright piano, makes up for the short board of the sound range of the piano, and widens the creation width of the composer.

Due to the application of the above-mentioned technical scheme, the present invention has the following advantages and effects compared with the existing upright piano soundboard:

1. The present invention sets the sound beam assembly on the outer wall of the soundboard. Because the bass has a large amplitude and low frequency relative to the treble, the bass resonance is concentrated in the central area of the soundboard close to the voice coil, and the treble resonance is concentrated in the surrounding edge area of the soundboard. The intensity of the central area of the soundboard plays an important role in improving the tone and sound quality of the bass area. Because the thickness of the soundboard is thick in the central area and thin in the surrounding area, the thickness of the soundboard is strengthened, and the strength of the central area of the soundboard is strengthened. Relatively speaking, it also changes the thickness difference between the central area of the soundboard and the surrounding edge area, which is also helpful for improving the tone and sound quality of the high-pitched area. can have a beneficial effect.

2. The present invention is provided with a cross-shaped groove on the outer wall of the soundboard, and the cross-shaped groove actually forms a cross-shaped sound tunnel on the outer wall of the soundboard. The tunnel) is rapidly transmitted to the surrounding edges of the soundboard, which plays a key role in improving the tone and quality of the treble.

3. In the present invention, four resonance areas are equally divided on the soundboard through the design of the sound beam assembly and the cross-shaped groove. When the piano is played, the vibration of the strings is first transmitted to the central area where the sound tunnel crosses, and then transmitted to the four resonance areas through the sound tunnel, and resonance and vibration are generated, thereby amplifying the sound of the strings into the resonance sound of the soundboard. Before the improvement, the piano can only generate three sound waves, that is, in the resonance chamber, the corresponding area of the soundboard is a resonance area, and the resonance area generates a sound wave, plus a sine wave, plus a percussion wave. A total of three sound waves. After the improvement, the piano of the present invention can generate six sound waves, wherein, four resonance regions generate four sound waves, plus one sine wave, and one firing wave, for a total of six sound waves. The volume of sound waves is the number of sound waves. For a specific stringed instrument, in addition to a string wave volume and a firing wave volume, it mainly depends on the number of resonance areas of the soundboard. Usually, each resonance area of the instrument produces one resonance area during performance. The amount of sound waves, how many resonance areas there are will generate how many sound waves. In addition, the amount of sound waves directly affects the timbre, penetration, and volume of the instrument. Therefore, the design of the present invention can obviously improve the timbre of the high-pitched region and the low-pitched region, and increase the penetrating power of the high-pitched region and the low-pitched region.

4. Each groove of the present invention adopts arc-shaped grooves, which can minimize the sudden change in thickness of the soundboard and avoid affecting the resonance and vibration of the soundboard.

Description of drawings

Accompanying drawing 1 is the structural representation of traditional upright piano soundboard;

2 is a schematic structural diagram of a soundboard according to an embodiment of the present invention (without connecting beams);

3 is a schematic structural diagram of a soundboard according to an embodiment of the present invention (with connecting beams);

4 is a schematic side view of a soundboard according to an embodiment of the present invention (without connecting beams);

5 is a schematic side view of the soundboard according to the embodiment of the present invention (with connecting beams);

6 is a schematic cross-sectional view of a sound board body according to an embodiment of the present invention;

7 is a schematic structural diagram of a sound beam assembly according to an embodiment of the present invention (with connecting beams);

8 is a schematic side view of a sound beam assembly according to an embodiment of the present invention (with connecting beams);

9 is a schematic structural diagram of a radiating sound beam according to an embodiment of the present invention;

10 is a schematic side view of a radiating sound beam according to an embodiment of the present invention.

In the above drawings: 1. soundboard; 2. 3. the first groove; 3. The second groove; Sound beam assembly; 4a. Strip sound beam member; 4b. 4. Connecting beams; 5. Radiation sound beam; 7. Resonance area; 8. Wooden base; Weight gain block.

Detailed ways

Below in conjunction with accompanying drawing and embodiment, the present invention is further described:

Embodiment: The present invention will be clearly described below with the drawings and detailed description. After any person skilled in the art understands the embodiments of the present invention, when the technology taught by the present invention can be changed and modified, it does not depart from the present invention. The spirit and scope of the invention.

Regarding the "connection" or "arrangement" used in this document, it can mean that two or more components or devices are in direct physical contact with each other, or they are in indirect physical contact with each other, or they can also refer to the mutual operation of two or more components or devices. or action.

As used herein, "comprising", "including", "having" and the like are open-ended terms, meaning including but not limited to.

Regarding the terms (terms) used in this article, unless otherwise specified, they usually have the ordinary meaning of each term used in this field, in the content of this case and in the special content. Certain terms used to describe the present case are discussed below or elsewhere in this specification to provide those skilled in the art with additional guidance regarding the description of the present case.

Referring to Figures 2 to 10, a soundboard with sound beams and sound tunnels in an upright piano, the soundboard 1 is rectangular, and its inner wall is arranged toward the strings of the piano.

The outer wall of the sound board 1 is provided with a first groove 2 and a second groove 3. The first groove 2 and the second groove 3 are crossed on the outer wall of the sound board 1 and pass through each other. The center of the soundboard 1 further divides the outer wall of the soundboard 1 into four resonance areas 6 equally.

The first groove 2 is located on the center line of the length direction of the sound board 1, and a transverse sound tunnel is formed on the outer wall of the sound board 1; the second groove 3 is located on the center line of the sound board 1 in the width direction, and is formed on the outer wall of the sound board 1. Longitudinal sound tunnel.

By opening a cross-shaped groove on the outer wall of the soundboard 1, the cross-shaped groove actually forms a cross-shaped sound tunnel on the outer wall of the soundboard 1, and the area close to the center collects the vibration of the strings, and then passes the cross-shaped sound. The tunnel is quickly transmitted to the surrounding edges of the soundboard 1, which plays a key role in improving the timbre and sound quality of the treble region. At the same time, by dividing the soundboard 1 into four resonant regions 6 equally, the vibration can be transmitted to the four resonant regions 6 through the sound tunnel, and resonance is generated, which can significantly improve the timbre of the high-pitched and low-pitched regions.

The center of the outer wall of the soundboard 1 is also provided with a sound beam assembly 4 , and the sound beam assembly 4 includes a plurality of strip-shaped sound beam members 4 a, and the strip-shaped sound beam members 4 a are arranged in pairs on the first groove 2 . both sides and both sides of the second groove 3 .

By arranging the sound beam assembly 4 on the outer wall of the soundboard 1, since the bass has a larger amplitude and lower frequency than the treble, the bass resonance is concentrated in the central area of the soundboard 1, and the treble resonance is concentrated in the surrounding edge area of the soundboard 1, which strengthens the soundboard. 1 The intensity of the central area plays an important role in improving the tone and sound quality of the bass area. Since the thickness of the soundboard 1 is a thickness gradient structure that is thick in the central area and thin around the periphery (ie, the design is thin on the outside and thick on the inside), the strength of the central area of the soundboard 1 is strengthened, and the central area and the surrounding edges of the soundboard 1 are relatively changed. The difference in the thickness of the area can also play a beneficial role in improving the tone and sound quality of the high-pitched area.

Preferably, as shown in Figures 3 and 5, a connecting beam 4b is provided between two adjacent sound beam members 4a, and the connecting beam 4b spans the first groove 2 and the second groove Above 3 , the sound beam assembly is formed in a well-shaped shape; and each of the connecting beams 4 b is located in the central area of the surface of the sound board 1 . A "mouth"-shaped reinforcing structure is formed by four connecting beams 4b, which further strengthens the bass region in the center of the soundboard 1, so as to further improve the sound quality of the piano bass region.

Preferably, the soundboard 1 is divided into a peripheral high-pitched region, a mid-range mid-range and a central low-pitched region from the sound frequency band; wherein, the wall thickness of the soundboard 1 gradually increases from the outside to the inside, forming the low-pitched region. The wall thickness is larger than that of the mid-range area, and the wall thickness of the mid-range area is larger than that of the treble area; by this design, by arranging the thicker bass area near the center, the frequency can be lower and the amplitude can be larger The low-frequency vibration of the soundboard 1 emits a thicker and more rounded bass in the bass region of the soundboard 1; by setting the thinner treble region away from the center, the high-frequency vibration with higher frequency and smaller amplitude can be made in the soundboard 1. The high-pitched range of the radiator produces clearer, brighter highs. The sound beam assembly 4 is located in the low-frequency region, which can further increase the load in the middle region of the soundboard 1 .

Preferably, as shown in FIGS. 7 and 8 , the strip-shaped sound beam member 4 a is composed of a wooden base 7 and a weighted block 8 connected to the wooden base 7 . With this design, the central area of the soundboard 1 can be further strengthened, which has a positive effect on improving the sound and sound quality of the low-frequency region.

Preferably, each of the resonance regions 6 of the soundboard 1 is respectively provided with a plurality of radiating sound beams 5 of the same number, the radiating sound beams 5 in the same resonance region are arranged in parallel, and at least one of the radiating sound beams One end of 5 faces the geometric center of soundboard 1 . In addition, the radiating sound beams 5 can also be radially arranged based on the center of the horizontal direction of the sound board 1 .

Preferably, the thickness of the inner end of the strip-shaped sound beam member 4a is greater than the thickness of the outer end, and the thickness of the inner end of the radiating sound beam 5 is greater than the thickness of the outer end. With this design, the central area of the soundboard 1 can be reinforced.

Preferably, the first grooves 2 and the second grooves 3 are arc-shaped grooves, which can minimize the sudden change in thickness of the soundboard 1 and avoid affecting the resonance and vibration of the soundboard 1 . The lengths of the first groove 2 and the second groove 3 are both smaller than the horizontal width of the soundboard 1 ; Smooth transition surface, so that the vibration is transmitted to the circumference of the soundboard 1 more evenly.

The following descriptions are made for other implementations of the present invention and structural changes:

1. In the above embodiment, the soundboard shown in the figure is only used for illustration, and its structure is not used to limit the protection scope of the present invention. within the scope of protection of the invention.

2. In the above embodiment, the number of the sound beam components 4 is not limited to one group, and can also be multiple groups of parallel or other designs that help to strengthen the load in the middle of the sound board 1, which is easily understood by those skilled in the art. and accepted.

3. In the above embodiment, the strip-shaped sound beam member 4a may have an arc and include a long side and a short side as shown in the figure, and the long sides of the adjacent two-shaped sound beam members 4a are arranged in pairs on the first The two sides of a groove 2 are arranged in pairs on both sides of the second groove 3 through the short sides of two adjacent sound beam members 4a;

Alternatively, the strip-shaped sound beam members 4 a may also be straight strips, which are combined at a 90-degree angle, and are arranged in pairs on both sides of the first groove 2 and both sides of the second groove 3 .

4. In the above embodiment, the first groove 2 and the second groove 3 are arc grooves. However, the present invention is not limited to this, and the grooves can be designed into other shapes, such as concave structures such as V-shape, U-shape, and W-shape. This is easily understood and accepted by those skilled in the art.

Compared with the prior art, in order to solve the problem that the existing upright pianos cannot take into account the high, middle and low frequency regions and have good resonant timbre, the present invention designs the soundboards in the existing upright pianos, especially the upright pianos. Improvements have been made. It is embodied in the following aspects: first, a sound beam assembly is erected on the outer wall of the sound board; second, a cross-shaped groove is opened on the outer wall of the sound board, thereby forming a cross-shaped sound tunnel on the outer wall of the sound board.

Aiming at the problem that the high-pitched area of the existing upright piano cannot be bright, and the low-pitched area is not rich and round enough, the present invention conducts an in-depth discussion and research on the design and sound production mechanism of the upright piano, and finds out the high-pitched area and the sound-producing mechanism of the existing upright piano. The main reason for the poor sound in the low range is due to the unreasonable soundboard design. Accordingly, the inventor broke the shackles of the previous upright piano composition design, and boldly proposed an improved design scheme of the present invention. This improved design scheme changes the soundboard from the previous free vibration mode to the current standard vibration mode, from vibration The angle of resonance and sound production solves the problem that the high-pitched area of the upright piano is not bright, and the low-pitched area is not rich and round enough. Practice has proved that the improved design scheme has outstanding substantive characteristics and significant technical progress, and has obtained obvious technical Effect.

In particular, the invention improves the soundboard in view of the relatively prominent sound quality problem in the low-frequency range of the existing upright piano, makes up for the short board of the sound range of the piano, and widens the creation width of the composer.

The above-mentioned embodiments are only intended to illustrate the technical concept and characteristics of the present invention, and the purpose is to enable those who are familiar with the art to understand the content of the present invention and implement accordingly, and cannot limit the protection scope of the present invention by this. All equivalent changes or modifications made according to the spirit of the present invention should be included within the protection scope of the present invention.

Claims (10)

1. a soundboard with sound beam and sound tunnel in an upright piano, is characterized in that: The soundboard (1) is rectangular, and its inner wall is arranged toward the strings of the piano; The outer wall of the soundboard (1) is provided with a first groove (2) and a second groove (3), wherein the first groove (2) is arranged laterally in the length direction of the soundboard (1), and the second groove (2) The groove (3) is longitudinally arranged in the width direction of the soundboard (1); The first groove (2) and the second groove (3) are crossed on the outer wall of the soundboard (1) and pass through each other, and the cross point is located in the center of the soundboard (1), thereby connecting the soundboard The outer wall of (1) is equally divided into four resonance areas (6); A sound beam assembly (4) is further provided in the center of the outer wall of the soundboard (1), and the sound beam assembly (4) includes a plurality of strip-shaped sound beam members (4a), and the strip-shaped sound beam members (4a) are arranged in pairs on both sides of the first groove (2) and on both sides of the second groove (3); The first groove (2) forms a transverse sound tunnel on the outer wall of the soundboard (1), and the second groove (3) forms a longitudinal sound tunnel on the outer wall of the soundboard (1). 2. The soundboard according to claim 1, characterized in that: the soundboard (1) is divided into a peripheral high-pitched region, a middle-sound region, and a central low-pitched region from the pronunciation frequency band; Wherein, the wall thickness of the soundboard (1) gradually increases from the outside to the inside, the wall thickness of the low-pitched area is larger than that of the mid-range area, and the wall thickness of the mid-range area is greater than that of the high-pitched area; The sound beam assembly (4) is located in the bass region. 3. The soundboard according to claim 1, characterized in that: the strip-shaped sound beam member (4a) is composed of a wooden base (7) and a weight gain connected to the wooden base (7). Block (8) constitutes. 4. The soundboard according to claim 1, characterized in that a connecting beam (4b) is provided between two adjacent strip-shaped sound beam members (4a), and the connecting beam (4b) spans across the Above the first groove (2) and the second groove (3), the sound beam assembly (4) is formed in a well-shaped shape; and each of the connecting beams (4b) is located on the soundboard ( 1) The central area of the surface. 5. The soundboard according to claim 1, characterized in that: a plurality of radiating sound beams (5) are respectively provided in each of the resonance regions (6) of the soundboard (1), and the sound beams (5) in the same resonance region are respectively provided with a plurality of radiating sound beams (5). Each radiating sound beam (5) is arranged in parallel, and one end of at least one of the radiating sound beams (5) faces the geometric center of the sound board (1) in the horizontal direction. 6. The soundboard according to claim 1, characterized in that: the soundboard (1) is further provided with a plurality of radiating sound beams (5), and the radiating sound beams (5) are located in each of the resonance areas (6), and are arranged radially based on the center of the horizontal direction of the soundboard (1). 7. The soundboard according to claim 5 or 6, characterized in that: the thickness of the inner end of the radiating sound beam (5) is greater than the thickness of the outer end. 8. The soundboard according to claim 1, characterized in that: the thickness of the inner end of the strip-shaped sound beam member (4a) is greater than the thickness of the outer end. 9 . The soundboard according to claim 1 , wherein the first groove ( 2 ) and the second groove ( 3 ) are arc-shaped grooves. 10 . 10. The soundboard according to claim 1, characterized in that: the lengths of the first groove (2) and the second groove (3) are both smaller than the horizontal width of the soundboard (1); A smooth transition surface is provided between the outer ends of the first groove (2) and the second groove (3) and the outer wall of the soundboard (1).

Images