Sound emission control device

Abstract

The present invention relates to a sound emission control device that improves the sound quality of sound provided by a sound device that emits sound in multiple directions. The sound emission control device (10) has multiple sound guides (40F, 40B) that have multiple inlets respectively connected to branch portions (33) that face a vibration surface of a diaphragm (111), multiple outlets provided to a sound device that face different directions from each other, and a horn-shaped inner wall that surrounds a space from each inlet to the outlets, and the multiple sound guides (40F, 40B) guide sound emitted from the vibration surface after being branched by the branch portions (33) to the multiple outlets.

Description

Technical Field

[0001] This invention relates to a sound playback control device for playing sound generated by a sound source in multiple directions in an audio device. Background Technology

[0002] Sound devices that amplify sound originating from a common sound source in multiple directions are known. For example, Patent Document 1 discloses an electronic musical instrument with a diffuser that branches the sound emitted from the speaker to the front and back sides of the electronic musical instrument.

[0003] Patent Document 1: Japanese Utility Model Application Publication No. 5-73695

[0004] However, in the electronic musical instrument disclosed in Patent Document 1, the sound emitted from the speaker is branched out by the diffuser and propagated over a wide area, and transmitted through multiple paths at different reflection points. Therefore, there is a problem that if the listener's head moves, the frequency characteristics of the sound heard by the listener change depending on the head position. Furthermore, since the sound is transmitted to the listener's head via multiple paths at different reflection points, there is a problem that the frequency characteristics of the sound heard by the listener have a large peak dip. Summary of the Invention

[0005] The present invention was made in view of the above description, and its purpose is to improve the sound quality provided by an audio device that emits sound in multiple directions.

[0006] The present invention provides a sound playback control device having multiple sound guides, each sound guide having: multiple inlets connected to branches respectively, the branches being opposite to a vibrating surface within a sound device; multiple outlets disposed in the sound device and facing different directions; and a horn-shaped inner wall surrounding the space from each inlet to the outlet. The multiple sound guides guide the sound emitted from the vibrating surface and the sound branched off by the branches to the multiple outlets. Attached Figure Description

[0007] Figure 1 This is a perspective view showing the structure of an electronic piano having one embodiment of the present invention, namely a sound control device.

[0008] Figure 2 This is an assembly diagram of the sound control device.

[0009] Figure 3 This is a perspective view of the sound control device.

[0010] Figure 4 yes Figure 3 Sectional view along line Ia-Ia'.

[0011] Figure 5 yes Figure 3 Sectional view of the Ib-Ib' line.

[0012] Figure 6 This is a top view illustrating the effects of this implementation method.

[0013] Figure 7 This is a perspective view showing the structure of another electronic piano with this playback control device.

[0014] Figure 8 This is an oblique view representing an electronic piano in another way.

[0015] Figure 9 yes Figure 8 Sectional view along line I-I'. Detailed Implementation

[0016] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

[0017] Figure 1 This is a perspective view showing the structure of an electronic piano 100 having one embodiment of the present invention, namely, the playback control devices 10L and 10R. (See attached image.) Figure 1 As shown, near the top surface of the electronic piano 100's frame, two speakers 110L and 110R are arranged side-by-side with their vibrating surfaces facing upwards. These speakers 110L and 110R are high-frequency speakers driven by sound signals generated based on keyboard playing.

[0018] Near the top of the front surface of the electronic piano 100's frame, there are two rectangular sound holes, 2FL and 2FR, arranged horizontally. Additionally, near the top of the back of the electronic piano 100's frame, there are two rectangular sound holes, 2BL and 2BR, arranged horizontally.

[0019] Here, the left-right positions of the centers of loudspeaker 110L, and sound holes 2FL and 2BL are the same. Similarly, the left-right positions of the centers of loudspeaker 110R, and sound holes 2FR and 2BR are the same. Furthermore, the distance from the center of loudspeaker 110L to the center of sound hole 2FL is the same as the distance from the center of loudspeaker 110L to the center of sound hole 2BL. Also, the distance from the center of loudspeaker 110R to the center of sound hole 2FR is the same as the distance from the center of loudspeaker 110R to the center of sound hole 2BR.

[0020] In this embodiment, a sound control device 10L is provided within the frame of the electronic piano 100. This sound control device 10L guides the sound branches emitted from the vibrating surface of the speaker 110L in two directions: towards the sound holes 2FL and 2BL. Additionally, a sound control device 10R is provided within the frame of the electronic piano 100. This sound control device 10R guides the sound branches emitted from the vibrating surface of the speaker 110R in two directions: towards the sound holes 2FR and 2BR. Hereinafter, in the electronic piano 100, the X-axis (left-right direction), the Y-axis (front-back direction), and the Z-axis (vertical direction) will be used to describe the structure of each part.

[0021] The sound control devices 10L and 10R have the same structure. Therefore, hereinafter, without distinction, they will be collectively referred to as sound control device 10. Similarly, loudspeakers 110L and 110R will also be collectively referred to as loudspeaker 110 without distinction. Furthermore, sound holes 2FL and 2FR will also be collectively referred to as sound hole 2F without distinction, and sound holes 2BL and 2BR will also be collectively referred to as sound hole 2B without distinction.

[0022] Figure 2 This is an assembly diagram showing the sound control device 10 installed on the loudspeaker 110. The sound control device 10 has a tray portion 20 provided on the loudspeaker 110 and a cover portion 30 provided on the tray portion 20.

[0023] The loudspeaker 110 has a hemispherical diaphragm 111 that vibrates in the Z-axis direction, and a magnetic gap (in) that accommodates the annular periphery of the diaphragm 111. Figure 2 The cylindrical magnetic circuit section 112 (illustrated in the middle, not shown in the figure) is shown.

[0024] The tray section 20 includes a horizontal plate section 21 and side wall sections 22FL, 22FR, 22BL, and 22BR. The horizontal plate section 21 has a planar shape formed by joining the upper bases of two isosceles trapezoidal plates, each having an upper base and a lower base longer than the upper base. The side wall sections 22FL and 22FR rise from the left and right hypotenuses of the isosceles trapezoidal region 21F on the front side of the horizontal plate section 21, respectively, while the side wall sections 22BL and 22BR rise from the left and right hypotenuses of the isosceles trapezoidal region 21B on the back side of the horizontal plate section 21, respectively. Furthermore, each of the side wall sections 22FL, 22FR, 22BL, and 22BR is approximately triangular in shape, and their height increases as they move from the center of the horizontal plate section 21 toward the front or back of the frame of the electronic piano 100.

[0025] In the central region of the horizontal plate portion 21, which is the region formed by joining the upper bases of the two isosceles trapezoids, a through hole 23 is provided to accommodate the hemispherical vibrating plate 111 exposed from the magnetic circuit portion 112. The tray portion 20 is provided on the upper surface of the magnetic circuit portion 112 with the vibrating plate 111 inserted into the through hole 23 and kept horizontal.

[0026] The cover portion 30 has a bottom wall portion 31, identical to the horizontal plate portion 21, consisting of an isosceles trapezoidal region 31F on the front side and an isosceles trapezoidal region 31B on the back side; a side wall portion 32L rising from the two inclined sides on the left side of the bottom wall portion 31; and a side wall portion 32R rising from the two inclined sides on the right side of the bottom wall portion 31. Here, the inclined sides on the left and right sides of the lower surface of the bottom wall portion 31 increase in distance from the horizontal plate portion 21 of the tray portion 20 as they move from the center toward the front and back sides, and are placed without gaps on the upper surfaces of the side wall portions 22FL, 22FR, 22BL, and 22BR of the tray portion 20.

[0027] On the lower surface of the bottom wall portion 31, the boundaries of the isosceles trapezoidal regions 31F and 31B form edge-shaped branches 33 that recede in a semi-circular shape towards the upward direction. The top edge of the semi-circular branch 33 lies in a plane encompassing both the X-axis and Z-axis passing through the center of the vibrating plate 111 over its entire length, and is approximately equally spaced from the vibration surface of the hemispherical vibrating plate 111.

[0028] When the bottom wall portion 31 is cut along a plane passing through both the X and Z axes while changing its position on the Y-axis, the cross-sectional shape of the lower end of the bottom wall portion 31 is semi-circular at the branch portion 33 on the Y-axis, but gradually changes to a straight shape as it moves along the Y-axis toward the front and back sides of the electronic piano 100. Furthermore, the cross-sectional shape of the lower end of the bottom wall portion 31 is straight at the front and back positions of the electronic piano 100.

[0029] Figure 3 This is a perspective view showing the structure of the sound control device 10. Figure 4 yes Figure 3 The Ia-Ia' line cross-sectional view, that is, a cross-sectional view of the sound control device 10 cut by a plane including the Z-axis passing through the center of the diaphragm 111 in the vertical direction and the X-axis passing through the center of the diaphragm 111 in the left-right direction of the electronic piano 100. Additionally, Figure 5 yes Figure 3 The Ib-Ib' line cross-sectional view is a cross-sectional view of the sound control device 10 cut off by a plane containing the Z-axis passing through the center of the diaphragm 111 in the vertical direction and the Y-axis passing through the center of the diaphragm 111 in the front-back direction of the electronic piano 100.

[0030] exist Figure 3 In the middle, the isosceles trapezoidal region 21F on the front side of the horizontal plate 21 of the tray 20, the side wall portions 22FL and 22FR, and the isosceles trapezoidal region 31F on the front side of the bottom wall portion 31 of the cover 30 constitute a sound guide 40F. The sound guide 40F guides the sound emitted from the vibrating surface of the diaphragm 111 and the sound after being branched by the branch portion 33 to the sound hole 2F on the front side of the electronic piano 100.

[0031] In addition, the isosceles trapezoidal region 21B on the back side of the horizontal plate 21 of the tray 20, the side wall portions 22BL and 22BR, and the isosceles trapezoidal region 31B on the back side of the bottom wall portion 31 of the cover 30 constitute a sound guide 40B. The sound guide 40B guides the sound emitted from the vibrating surface of the diaphragm 111 and the sound branched by the branch portion 33 to the sound hole 2B on the back side of the electronic piano 100.

[0032] Sound guides 40F and 40B are two sound guides, each having: two inlets connected to branch sections 33, which are opposite to the diaphragm 111; two outlets, sound holes 2FL (2FR) and 2BL (2BR), located on the electronic piano 100 and facing opposite directions; and a horn-shaped inner wall surrounding the space from each inlet to the outlet. Sound guides 40F and 40B guide the sound emitted from the diaphragm 111 and branched by the branch sections 33 to the two outlets. Sound guides 40F and 40B have the same shape and size. Therefore, in this embodiment, the sound branched by the branch sections 33 is injected into sound guides 40F and 40B with the same sound pressure and guided with the same sound pressure.

[0033] Sound guides 40F and 40B are horn-shaped sound guides whose opening cross-sectional area continuously expands from the vibrating plate 111 side toward the sound outlets 2F and 2B side. The shape of the inner wall surface of sound guides 40F and 40B continuously changes from their inlet to their outlet. This is described in more detail below.

[0034] In this embodiment, the sound guide 40F has two side surfaces (sidewalls 22FL and 22FR) that are approximately triangular in shape and have two sides that are further apart from each other as they move from the inlet to the outlet; and two bottom surfaces (isosceles trapezoidal region 21F of the horizontal plate 21 and isosceles trapezoidal region 31F of the bottom wall 31) that are approximately trapezoidal in shape and have a width that expands as it moves from the inlet to the outlet. The cross-sectional area of ​​the sound guide 40F increases as it moves from the vibrating plate 111 side to the sound outlet 2F side. The sound guide 40B is similar, having side surfaces that are approximately triangular in shape and bottom surfaces that are approximately trapezoidal in shape, with the cross-sectional area of ​​the opening increasing as it moves from the vibrating plate 111 side to the sound outlet 2B side.

[0035] like Figure 4 and Figure 5 As shown, a voice coil 113 is wound around the periphery of the diaphragm 111, and the voice coil 113 is housed in the magnetic gap 114 of the magnetic circuit section 112. The diaphragm 111 vibrates in the direction of the drive shaft Z, which passes through the center of the diaphragm 111 in the vertical direction, by energizing the voice coil 113. Thus, the vibrating surface of the diaphragm 111 emits sound. Furthermore, in Figure 4 In the middle, side wall portions 29L and 29R are components of the tray portion 20 that support side wall portions 32L and 32R. Figure 4 Illustrations are omitted from other diagrams.

[0036] In the bottom wall portion 31, the plane containing the drive shaft Z and orthogonal to the front and rear axes Y forms the boundary of the isosceles trapezoidal region 31F of the sound guide 40F and the isosceles trapezoidal region 31B of the sound guide 40B. Furthermore, the branch portion 33 lies within the plane containing the drive shaft Z and orthogonal to the front and rear axes Y. The length of the branch portion 33 is approximately the same as the diameter of the vibrating plate 111.

[0037] As described above, in this embodiment, the inlets of the sound guides 40F and 40B, which are multiple sound guides, are connected to the branch 33, which faces the vibrating surface of the diaphragm 111. Furthermore, the sound guides 40F and 40B guide the sound emitted from the vibrating surface of the diaphragm 111 and branched by the branch 33 in different directions. More specifically, the sound guides 40F and 40B guide the sound in multiple directions orthogonal to and different from the drive axis Z of the vibrating surface of the diaphragm 111; specifically, they guide the sound in opposite directions, i.e., in the directions of the sound holes 2F and 2B.

[0038] Additionally, if we focus on the cross-sectional shape of the sound guides 40F and 40B, which are cut using a plane that includes the drive shaft Z and the front and rear shafts Y ( Figure 5 In the isosceles trapezoidal regions 31F and 31B of the bottom wall portion 31, the inner wall regions of the sound guides 40F and 40B connected to the branch portion 33 are specifically, the isosceles trapezoidal regions 31F and 31B of the bottom wall portion 31 form an obtuse angle θ with the drive shaft Z moving downward from the branch portion 33.

[0039] The shapes of the inner wall surfaces of sound guides 40F and 40B are as described below. Furthermore, since the inner wall surfaces of sound guides 40F and 40B are identical, only the shape of the inner wall surface of sound guide 40F will be described below.

[0040] The lower inner wall surface of the sound guide 40F, i.e., the upper surface of the horizontal plate portion 21, is horizontal throughout the entire area. Therefore, the inner wall of the sound guide 40F has a flat portion at least in one part.

[0041] The inner wall surfaces of the sides of the sound guide 40F, namely the inner wall surfaces of the side wall portions 22FL and 22FR, are vertically aligned throughout the entire area. Furthermore, the inner wall surfaces of the side wall portions 22FL and 22FR move further apart from each other as they move from the diaphragm 111 side toward the sound hole 2F side, and their gradients relative to their respective front-rear axes Y increase.

[0042] The lower surface of the isosceles trapezoidal region 31F of the bottom wall portion 31, which is the inner wall surface of the upper side of the sound guide 40F, moves away from the inner wall surface of the lower side of the sound guide 40F as it moves from the vibrating plate 111 side toward the sound outlet 2F side. Furthermore, the lower surface of the isosceles trapezoidal region 31F of the bottom wall portion 31, which is cut by a plane orthogonal to the front and rear axes Y, is semi-circular at the branch portion 33, and continuously changes from a semi-circular shape to a straight line shape as it moves toward the sound outlet 2F side.

[0043] Figure 6 This is a top view showing an electronic piano 100 positioned in front of the wall 200, and users U1 and U2 listening to the sound emitted from the electronic piano 100. See below for reference. Figure 6 The effects of this implementation method will be explained.

[0044] When playing the electronic piano 100, sound is emitted from the vibrating surfaces of the diaphragms 111 of the speakers 110L and 110R. Here, assuming that the playback control devices 10L and 10R with sound guides 40F and 40B are not provided, and the sound emitted from the vibrating surfaces of the diaphragms 111 of the speakers 110L and 110R is simply branched into two parts, one to the front and one to the back, the branched sound propagates over a wide area. Therefore, sound reaches the ears of users U1 and U2 via multiple paths through different reflection points. Consequently, users U1 and U2 hear a sound with a large peak angle in its frequency response.

[0045] However, the electronic piano 100 in this embodiment is provided with playback control devices 10L and 10R, each having sound guides 40F and 40B. Therefore, the sound emitted from the vibrating surface of the speaker 110L is branched to the front and rear sides via the branch 33 of the playback control device 10L, and guided by the sound guides 40F and 40B of the playback control device 10L to be emitted from the sound holes 2FL and 2BL. Similarly, the sound emitted from the vibrating surface of the speaker 110R is branched to the front and rear sides via the branch 33 of the playback control device 10R, and guided by the sound guides 40F and 40B of the playback control device 10R to be emitted from the sound holes 2FR and 2BR.

[0046] Here, the spaces from the inlet (branch 33) to the outlet (sound holes 2F and 2B) of each of the sound guides 40F and 40B are surrounded by an inner wall surface with a continuously changing horn shape from the inlet to the outlet. Therefore, the directivity of the sound guided to the outlets of each of the sound guides 40F and 40B does not change with frequency in either the horizontal or vertical directions, and the sound guides 40F and 40B function as directional horns capable of producing a uniform radiation pattern. Therefore, the sound heard by user U1 is a high-quality sound with no large peak tilt angle in the frequency response.

[0047] Furthermore, in this embodiment, the two sound guides 40F that direct sound to the left and right sound holes 2FL and 2FR of the electronic piano 100 are of the same shape and function as directional speakers with the same characteristics, so that the user hears the sound emitted from the sound holes 2FL and 2FR. Therefore, even when the user U1 moves their head to the left or right, the user U1 can hear a sound with uniform frequency characteristics over a large area.

[0048] Furthermore, the sound control devices 10L and 10R of this embodiment each have sound guides 40F and 40B that guide the sound in two different directions. Therefore, as Figure 6 As illustrated, the sounds emitted from speakers 110L and 110R are guided by the sound guides 40F of the playback control devices 10L and 10R to the sound holes 2FL and 2FR, and by the sound guides 40B of the playback control devices 10L and 10R to the sound holes 2BL and 2BR on the rear side of the electronic piano 100, where they are reflected by the wall surface 200. Therefore, user U1 and user U2 behind him hear additional sound from the reflected sound from the wall surface 200 to the sound from the sound holes 2FL and 2FR.

[0049] Here, for the sound heard by user U1, the sound from the sound holes 2FL and 2FR is stronger than the reflected sound from the wall 200. Similarly, for the sound heard by user U2, the sound from the sound holes 2FL and 2FR is also stronger than the reflected sound from the wall 200, but compared to user U1, user U2 is more likely to perceive the reflected sound from the wall 200. However, the reflection of sound from the wall 200 creates a sound diffusion effect.

[0050] Therefore, the sound heard by user U1, the performer, is a broad sound, much like that emitted from a native piano. On the other hand, high-frequency sounds that would otherwise be attenuated in a typical configuration without the playback control device 10 are transmitted to user U2, located behind user U1 and at a distance, via the operation of the playback control device 10. Reflected sounds, diffused by reflections from the wall, are also transmitted to user U2. Therefore, the sound heard by user U2 is close to that of a piano and has an expanded sound image. As described above, according to this embodiment, the sound quality of the electronic piano 100 can be improved for both the performer and the listener, who is located far from the performer.

[0051] <Other Implementation Methods>

[0052] The above description illustrates one embodiment of the present invention, but other embodiments are conceived for the present invention. For example, as described below.

[0053] (1) In the above embodiment, the sound emitted from the vibrating surface is branched into two parts, but it is also possible to provide a branch that branches into three or more parts, and three or more sound guides that connect each inlet to the branch and guide the sound to three or more outlets that are oriented in different directions.

[0054] (2) In the above embodiment, two playback control devices 10 are provided in the electronic piano 100, but playback control devices 10 can also be provided in audio devices other than the electronic piano 100, such as speakers. In addition, the number of playback control devices 10 provided in the audio device is arbitrary.

[0055] (3) In the above embodiment, the bottom wall surfaces of the sound guides 40F and 40B are set as isosceles trapezoids, but they can also be set as trapezoids with two hypotenuses of different lengths.

[0056] (4) In the above embodiment, the sound guides 40F and 40B guide the sound in the direction of front and back of the electronic piano 100, but they can also guide it in a direction that is tilted relative to the front and back direction.

[0057] (5) Figure 7 This is a perspective view showing the structure of another electronic piano 100a having the playback control device described in the above embodiment. In the above embodiment ( Figure 1 In the electronic piano 100, speakers 110L and 110R, facing upwards, and left and right playback control devices 10L and 10R are arranged near the top surface of the frame. In contrast, in... Figure 7In the illustrated electronic piano 100a, speakers 110L and 110R, facing upwards, and left and right playback control devices 10L and 10R are arranged below the keyboard section 202 within the frame. Furthermore, in the electronic piano 100a, sound holes 2FL and 2FR for the playback control devices 10L and 10R are located below the keyboard section 202 on the front 201F of the frame, and sound holes 2BL and 2BR for the playback control devices 10L and 10R are located below the keyboard section 202 on the rear 201B of the frame. This configuration achieves the same effects as the embodiment described above.

[0058] (6) Figure 8 This is a perspective view showing an electronic piano in other ways. Additionally, Figure 9 yes Figure 8 A sectional view along line I-I'. In Figure 8 and Figure 9 The electronic piano 100b shown is... Figure 7 Similar to the electronic piano 100a, speakers 110L and 110R, facing upwards, are positioned below the keyboard section 202 within the frame. More specifically, two spaces are provided within the frame to accommodate the left and right speakers 110L and 110R below the keyboard section 202. Figure 9 The diagram shows one of the two spaces, 203L. Within this space 203L, a speaker 110L with its sound output direction facing upwards is supported. Furthermore, on the front surface 201F and back surface 201B of the frame, below the keyboard section 202 on the lower left side, are sound holes 205FL and 205BL, connecting space 203L to the outside of the frame. Although not shown in the diagram, a space identical to space 203L is also provided for the speaker 110R on the right side. Additionally, on the front surface 201F and back surface 201B of the frame, below the keyboard section 202 on the lower right side, are sound holes 205FR and 205BR, connecting the space housing the speaker 110R to the outside of the frame. Furthermore, in this example, the two speakers 110L and 110R are housed in two separate spaces, but they could also be housed in a single space.

[0059] In this electronic piano 100b, the sound emitted upwards from the left and right speakers 110L and 110R is branched to the front 201F side and the rear 201B side, respectively, from the sound holes 205FL and 205FR on the front side and the sound holes 205BL and 205BR on the rear side. Here, when the listener is positioned in front of the electronic piano 100b, the sound emitted from the front sound holes 205FL and 205FR is directly transmitted to the listener, while the sound emitted from the rear sound holes 205BL and 205BR is transmitted to the listener after reflection from the wall. Therefore, an auditory sense of expansion is achieved for the sound heard by the listener.

[0060] Explanation of the label

[0061] 100, 100a, 100b... Electronic piano; 110, 110L, 110R... Speaker; 111... Vibrating plate; 112... Magnetic circuit; 113... Voice coil; 114... Magnetic gap; 2FL, 2FR, 2BL, 2BR, 2F, 2B, 205FL, 205FR, 205BL, 205BR... Sound holes; 10, 10L, 10R... Sound control device; 40F, 40B... Sound guide; 33 ...Branch section, 20...Tray section, 30...Cover section, 21...Horizontal plate section, 21F, 21B, 31F, 31B...Isosceles trapezoidal area, 22FL, 22FR, 22BL, 22BR, 32L, 32R, 29L, 29R...Side wall section, 23...Through hole, 31...Bottom wall section, U1, U2...User, 201F...Front surface, 201B...Back side, 202...Keyboard section, 203L...Space.

Claims

1. A sound playback control device having a plurality of sound guides, the plurality of sound guides having: a plurality of inlets, each connected to a branch, the branch being opposite a vibrating surface within a sound device; a plurality of outlets disposed in the sound device and oriented in different directions; and a horn-shaped inner wall surrounding the space from each inlet to the outlet. The horn-shaped inner wall is formed by two bottom walls and two side walls that are approximately triangular in shape, with two sides that are further apart from each other as they move from the inlet to the outlet of the sound guide. The gradient of the inner wall surface of the two side walls increases relative to the direction from the inlet to the outlet, i.e., the front-rear axis direction of the sound guide. The multiple sound guides will emit sound from the vibrating surface and guide the sound from the branched portion to the multiple outlets.

2. The sound playback control device according to claim 1, wherein, The plurality of sound guides direct sound in multiple directions that are orthogonal to and different from the driving direction of the vibrating surface. The inner wall region of the sound guide connected to the branch forms an obtuse angle with the driving direction.

3. The sound playback control device according to claim 1 or 2, wherein, The inner walls of the plurality of sound guides have at least a portion of a planar portion.

4. The sound playback control device according to claim 1 or 2, wherein, The multiple sound guides are two sound guides that direct sound in opposite directions.

5. The sound playback control device according to claim 1 or 2, wherein, The cross-sectional area of ​​the openings of the plurality of sound guides increases as they move away from the vibrating surface.

6. The sound playback control device according to claim 5, wherein, The two bottom walls are approximately trapezoidal in shape, with their width increasing as they move from the inlet to the outlet of the sound guide.

7. The sound playback control device according to claim 6, wherein, The vibration surface is hemispherical. In the sound guide, the cross-sectional shape of the inner wall surface on the side opposite to the vibrating surface changes continuously from a semi-circular shape to a straight shape as it moves from the inlet to the outlet of the sound guide.

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