Speaker system

Abstract

To provide a speaker system that is configured to enable an output range of sound to be switched.SOLUTION: A vehicle approach notification device 100 is provided with: a running sound generating part 110 that generates sound to be outputted; a speaker array 120 including a plurality of speakers 122 to which sound generated by the running sound generating part 110 can be selectively inputted; an SP driving part 130 that switches one or the plurality of speakers 122 to which the generated sound is inputted; and a switching control part 140 that instructs the SP driving part 130 to switch the speakers in accordance with whether directional characteristics of sound outputted from the speaker array 120 are wide or narrow.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a speaker system that combines a plurality of speakers. [Background technology]

[0002] Conventionally, a vehicle presence warning device has been known that uses a speaker array combining multiple ultrasonic speakers and changes the directivity of the warning sound by adjusting the phase of the sound waves output from each ultrasonic speaker (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2011-31695 A Summary of the Invention [Problem to be solved by the invention]

[0004] Incidentally, the vehicle presence notification device disclosed in the above-mentioned Patent Document 1 can change the directivity of the entire speaker array by adjusting the phase of the sound waves output from each speaker constituting the speaker array, but cannot change the output range of the notification sound. For example, it cannot switch between outputting sound to a long distance and outputting sound to a wide area around the vehicle depending on the situation of the vehicle while it is moving.

[0005] The present invention has been made in view of the above-mentioned points, and an object of the present invention is to provide a speaker system capable of switching the sound output range. [Means for solving the problem]

[0006] In order to solve the above-mentioned problems, the speaker system of the present invention includes an output sound generating means for generating a sound to be output, a speaker array including a plurality of speakers to which the sound generated by the output sound generating means can be selectively input, a speaker switching means for switching one or more speakers to which the generated sound is input, and a switching instruction means for instructing the speaker switching means to switch in accordance with the width of the directional characteristics of the sound output from the speaker array. Specifically, the above-mentioned speaker switching means selectively switches between a first region having a large area and including a large number of speakers, and a second region having a small area and including a small number of speakers.

[0007] By using speakers that are located in a narrow area from among the multiple speakers that make up the speaker array, the directional characteristics of the speaker array will be broader, and by using speakers that are located in a wide area, the directional characteristics of the speaker array will be narrower, so by switching the area in which the speakers are arranged, it is possible to switch the output range of the sound radiated by the speaker array.

[0008] It is also preferable that the device further includes a surrounding situation determination means for determining the surrounding situation, and the switching instruction means issues a switching instruction based on the surrounding situation determined by the surrounding situation determination means. This makes it possible to automatically switch between wide and narrow directional characteristics in accordance with the surrounding situation.

[0009] Also, in a speaker system mounted on a vehicle and outputting a sound to notify people in the vicinity of an approaching vehicle, the surrounding situation determination means is a speed acquisition means for acquiring the traveling speed of the vehicle, and the switching instruction means desirably issues a switching instruction to select a first region so that the directional characteristics of the sound output from the speaker array become narrower when the traveling speed acquired by the speed acquisition means is fast, and to select a second region so that the directional characteristics of the sound output from the speaker array become wider when the traveling speed acquired by the speed acquisition means is slow. This makes it possible to widely hear the sound informing pedestrians and the like around the vehicle of the approach when traveling at low speed, and to hear the sound informing pedestrians and the like at a short distance away that a vehicle is approaching when traveling at medium speed or faster.

[0010] Also, in a speaker system mounted on a vehicle and outputting a sound to notify people in the vicinity of an approaching vehicle, the surrounding situation determination means is a driving environment determination means for determining whether the vehicle is traveling in an urban area or a suburban area, and the switching instruction means desirably issues a switching instruction to select a first region so that the directional characteristics of the sound output from the speaker array become narrower when the driving environment determination means determines that the vehicle is traveling in a suburban area, and to select a second region so that the directional characteristics of the sound output from the speaker array become wider when the driving environment determination means determines that the vehicle is traveling in an urban area. This makes it possible to widely announce the approach of pedestrians around the vehicle in urban areas where there is a high possibility of many pedestrians around the vehicle, and to announce the approach of a vehicle to pedestrians at a short distance away in suburban areas where there are relatively few people.

[0011] In addition, it is preferable that the switching instruction means issues a switching instruction to alternately select the first area and the second area, thereby making it possible to make the sound emitted from the speaker array audible in both near and far surrounding spaces.

[0012] It is also preferable that the surrounding situation determination means has an imaging means for imaging the surroundings and an image analysis means for analyzing the surrounding situation based on the image obtained by the imaging means, and the switching instruction means issues a switching instruction to select either the first area or the second area based on the surrounding situation analyzed by the image analysis means. This makes it possible to switch between wide and narrow directional characteristics of the radiated sound of the speaker array after accurately grasping the surrounding situation.

[0013] It is also preferable that the surrounding situation determination means is a congestion state determination means for determining the surrounding congestion state, and the switching instruction means issues a switching instruction to select either the first area or the second area based on the surrounding congestion state determined by the congestion state determination means. This makes it possible to switch between wide and narrow directional characteristics of the radiated sound of the speaker array according to the surrounding congestion state. [Brief description of the drawings]

[0014] [Figure 1] 1 is a diagram showing a configuration of a vehicle approach notification device according to an embodiment; [Diagram 2] FIG. 2 is a diagram showing the configuration of a speaker array. [Diagram 3] 1 is a diagram illustrating the correspondence between the width of a directional characteristic and a speaker to be used. FIG. [Figure 4] FIG. 11 is an explanatory diagram of a sound field when the directional characteristics are switched. [Diagram 5] 11 is a diagram showing a modified example of an area N set in a speaker array. FIG. [Figure 6] FIG. 13 is a diagram showing another modified example of the area N set in the speaker array. [Figure 7] 11A and 11B are diagrams showing modified examples of an area W set in a speaker array. [Figure 8] 13 is a diagram showing another modified example of the areas N and W set in the speaker array. FIG. [Figure 9] 11A and 11B are diagrams showing a specific example of switching the directional characteristics of a speaker array in accordance with the traveling speed of a vehicle. [Figure 10]11A and 11B are diagrams showing a specific example in which the directional characteristics of a speaker array are switched depending on whether the vehicle is traveling in an urban area or in the suburbs. [Figure 11] 11A and 11B are diagrams showing a specific example of a case where the surrounding situation is determined based on an image captured of the surroundings. [Figure 12] FIG. 13 is a diagram showing a modified example in which the directional characteristics of a speaker array are changed depending on the level of congestion in a room. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a vehicle approach notification device according to an embodiment of the present invention will be described with reference to the drawings.

[0016] Fig. 1 is a diagram showing the configuration of a vehicle approach notification device according to an embodiment. The vehicle approach notification device 100 shown in Fig. 1 is mounted on a vehicle (e.g., an electric vehicle) that produces quiet running sounds, and outputs simulated running sounds around the vehicle to notify surrounding pedestrians and the like of the approach of the vehicle. For this purpose, the vehicle approach notification device 100 includes a running sound generation unit 110, a speaker array 120, an SP (speaker) driving unit 130, a switching control unit 140, and a surrounding situation determination unit 150.

[0017] The running sound generating unit 110 generates a predetermined sound to notify pedestrians around the vehicle of the approach of the vehicle. This generated sound is assumed to be a simulated running sound of a vehicle, but since the purpose is to notify pedestrians of the approach of a vehicle with sound, it does not necessarily have to be similar to a running sound, and other notification sounds may also be used.

[0018] The speaker array 120 includes a plurality of speakers to which the generated sound output from the running sound generating unit 110 is selectively input, and is set at the front of the vehicle. Each speaker is, for example, an ultrasonic speaker, and emits a sound in the audible band corresponding to the input generated sound.

[0019] The speaker 122 (FIG. 2) reproduces audible sound with narrow directional characteristics by utilizing waveform distortion caused by emitting two types of ultrasonic waves with high sound pressure. If the frequency of one ultrasonic wave (carrier wave) is f1, distortion components of integer multiples 2f1, 3f1, 4f1, ... are generated. If the frequency of the other ultrasonic wave (carrier wave) is f2, distortion components of integer multiples 2f2, 3f2, 4f2, ... are generated. If the frequencies f1 and f2 are both ultrasonic waves (sounds with frequencies higher than the human audible band), these integer multiple distortions are also higher than the audible band and cannot be heard by the human ear. However, when ultrasonic waves of such two types of carrier waves are emitted simultaneously, components of the difference tone (frequency is f2-f1) and the chord tone (frequency is f1+f2) are generated. Of these, by setting the frequency of the difference tone (f2-f1) to be within the audible band, it becomes possible to emit the generated sound as an audible sound from the ultrasonic speaker 122. For example, if f1 is 41 kHz and f2 is 40 kHz, it is possible to radiate the difference sound of f2-f1=1 kHz.

[0020] Fig. 2 is a diagram showing the configuration of the speaker array 120. As shown in Fig. 2, the speaker array 120 of this embodiment has a total of 64 ultrasonic speakers 122 arranged without any gaps in eight rows and eight columns.

[0021] The SP driving unit 130 can selectively input an amplified signal of the sound generated by the running sound generating unit 110 to one or more speakers 122 included in the speaker array 120, and by changing this selection state, the width of the area in which the one or more speakers 122 emitting sound are arranged can be switched.

[0022] The switching control unit 140 instructs the SP driving unit 130 to switch the area (active area) that includes the speaker 122 emitting the sound, in accordance with the width or narrowness of the directional characteristics of the sound output from the speaker array 120.

[0023] The surrounding situation determination unit 150 determines the surrounding situation. The switching control unit 140 issues a switching instruction based on the surrounding situation determined by the surrounding situation determination unit 150.

[0024] The above-mentioned running sound generating unit 110 corresponds to the output sound generating means, the SP driving unit 130 corresponds to the speaker switching means, the switching control unit 140 corresponds to the switching instruction means, and the surrounding situation determining unit 150 corresponds to the surrounding situation determining means.

[0025] The vehicle approach notification device 100 of this embodiment has the above-mentioned configuration. Next, the operation of switching between wide and narrow directional characteristics will be described.

[0026] Fig. 3 is a diagram for explaining the relationship between the width of the directional characteristic and the speaker 122 to be used. Fig. 3(A) shows an example of using the speaker 122 when the directional characteristic is wide, and Fig. 3(B) shows an example of using the speaker 122 when the directional characteristic is narrow.

[0027] To widen the directional characteristics, it is necessary to reduce the number of speakers 122 that emit sound and narrow the area in which these speakers 122 are arranged. In Fig. 3(A), a small number (4 x 4 = 16 speakers in the center) of speakers 122 included in the narrow area N (second area) are selected, and sound is emitted from these 16 speakers 122.

[0028] On the other hand, if it is desired to narrow the directional characteristics, it is necessary to increase the number of speakers 122 that radiate sound and to widen the area in which these speakers 122 are arranged. In Fig. 3(B), a large number (8 x 8 = 64 speakers in total) of speakers 122 included in the wide area W (first area) are selected, and sound is radiated from these 64 speakers 122.

[0029] Fig. 4 is an explanatory diagram of the sound field when the directional characteristics are switched. As shown in Fig. 4(A), a wide directional characteristic is obtained by radiating sound from a small number of speakers 122 included in the area N (Fig. 3(A)), so that the sound is radiated over a wide range from the speaker array 120 installed at the front of the vehicle. In this case, the sound is diffused widely and easily attenuated along the radiation direction, so that pedestrians and the like in the vicinity can hear the sound.

[0030] On the other hand, as shown in Fig. 4(B), by radiating sound from a large number of speakers 122 included in the area W (Fig. 3(B)), a narrow directional characteristic is obtained, and sound is radiated toward a narrow range from the speaker array 120 installed at the front of the vehicle. In this case, the sound is not diffused much and is not easily attenuated along the radiation direction, so pedestrians at a long distance can hear the sound.

[0031] In this way, by using speakers 122 included in narrow region N from among the multiple speakers 122 that make up speaker array 120, the directional characteristics of speaker array 120 will be broader, and by using speakers 122 included in wide region W, the directional characteristics of speaker array 120 will be narrower. Therefore, by switching between regions N and W in which speakers 122 are arranged, it is possible to switch the output range of the sound radiated by speaker array 120.

[0032] Figure 5 is a diagram showing a modified example of the area N set in the speaker array 120. The area N with wide directivity shown in Figure 5(a) includes 8 x 4 = 32 speakers 122. By emitting sound from these speakers 122, it is possible to widen the directivity in the horizontal direction and narrow the directivity in the vertical direction. The area W with narrow directivity shown in Figure 5(B) is the same as that shown in Figure 3(B).

[0033] Fig. 6 is a diagram showing another modified example of the area N set in the speaker array 120. The area N with wide directivity shown in Fig. 5(A) has a trapezoid shape with a short bottom side and a long top side, and includes a total of 20 speakers 122. By emitting sound from these speakers 122, it is possible to narrow the horizontal directivity near the top side where eight speakers 122 are arranged horizontally, and to widen the horizontal directivity near the bottom side where two speakers 122 are arranged horizontally. The area W with narrow directivity shown in Fig. 6(B) is the same as that shown in Fig. 3(B).

[0034] Fig. 7 is a diagram showing a modified example of the area W set in the speaker array 120. The area W with narrow directivity shown in Fig. 7(B) includes a total of 48 speakers 122 arranged in two rows along the periphery. By emitting sound from these speakers 122, it is possible to narrow the directivity, as in the case shown in Fig. 3(B). Note that the area N with wide directivity shown in Fig. 7(A) is the same as that shown in Fig. 3(A).

[0035] Fig. 8 is a diagram showing another modified example of the regions N and W set in the speaker array 120. The regions N1 and N2 with wide directional characteristics shown in Fig. 8(A) include a total of 8 x 8 = 64 speakers 122, of which the output sound pressure of the 4 x 4 = 16 speakers 122 in the central region N1 is large, and the output sound pressure of the 48 speakers 122 in the surrounding region N2 is small. The regions W1 and W2 with narrow directional characteristics shown in Fig. 8(B) include a total of 8 x 8 = 64 speakers 122, of which the output sound pressure of the 4 x 4 = 16 speakers 122 in the central region W1 is small, and the output sound pressure of the 48 speakers 122 in the surrounding region W2 is large. In this way, even if the number of speakers 122 used is the same, the directional characteristic of the speaker array 120 can be widened by setting a central area N1 that includes speakers 122 with high sound pressure, and the directional characteristic of the speaker array 120 can be narrowed by setting a peripheral area W2 that includes speakers 122 with high sound pressure.

[0036] Next, a specific example of the surrounding condition determining unit 150 will be described.

[0037] Fig. 9 is a diagram showing a specific example of switching the directional characteristics of speaker array 120 according to the traveling speed of the vehicle. Vehicle approach notification device 100A shown in Fig. 9 differs from vehicle approach notification device 100 shown in Fig. 1 in that surrounding condition determination unit 150 is realized by speed acquisition unit 150A, and switching control unit 140 is replaced with switching control unit 140A. Speed ​​acquisition unit 150A corresponds to speed acquisition means.

[0038] The speed acquisition unit 150A acquires the traveling speed of the vehicle. For example, the traveling speed may be detected based on a vehicle speed pulse output every certain distance traveled, or the traveling speed may be acquired from a vehicle control unit or the like that performs display processing such as a speedometer. Note that, since the relative speed of pedestrians and the like around the vehicle changes depending on the traveling speed of the vehicle, the traveling speed of the vehicle is also included in the "surrounding conditions" in this specification and the like.

[0039] The switching control unit 140A issues a switching instruction to the SP driving unit 130 to select area W so that the directional characteristics of the sound output from the speaker array 120 will be narrow when the driving speed acquired by the speed acquisition unit 150A is fast, and to select area N so that the directional characteristics of the sound output from the speaker array 120 will be wide when the driving speed acquired by the speed acquisition unit 150A is slow.

[0040] This allows the sound to be widely heard by pedestrians around the vehicle when the vehicle is traveling at low speed, and the sound to notify pedestrians at a short distance away that a vehicle is approaching can be heard when the vehicle is traveling at medium speed or higher.

[0041] Fig. 10 is a diagram showing a specific example in which the directional characteristics of speaker array 120 are switched depending on whether the vehicle is traveling in an urban area or in the suburbs. Vehicle approach notification device 100B shown in Fig. 10 differs from vehicle approach notification device 100 shown in Fig. 1 in that surrounding condition determination unit 150 is realized by driving environment determination unit 150B, and switching control unit 140 is replaced by switching control unit 140B. Driving environment determination unit 150B corresponds to the driving environment determination means.

[0042] The driving environment determination unit 150B determines whether the driving position of the vehicle is in an urban area or a suburb. For example, a vehicle navigation device that continuously or at regular intervals processes whether the vehicle position is included in an urban area or a suburb based on map data may be used as the driving environment determination unit 150B, or information indicating whether the vehicle is driving in an urban area or a suburb may be obtained from the vehicle navigation device.

[0043] When the driving environment determination unit 150B determines that the vehicle is traveling in a suburban area, the switching control unit 140B issues a switching instruction to the SP driving unit 130 to select area W so that the directional characteristics of the sound output from the speaker array 120 will be narrow, and when the driving environment determination unit 150B determines that the vehicle is traveling in an urban area, the switching control unit 140B issues a switching instruction to the SP driving unit 130 to select area N so that the directional characteristics of the sound output from the speaker array 120 will be wide.

[0044] This allows a sound to be played widely to pedestrians around the vehicle in urban areas where there is a high possibility that there will be many pedestrians around the vehicle, and a sound to notify pedestrians around the vehicle of the approach can be played to pedestrians at a short distance away in suburban areas where there are relatively few people.

[0045] Fig. 11 is a diagram showing a specific example of determining the surrounding situation based on an image of the surroundings. The vehicle approach notification device 100C shown in Fig. 11 differs from the vehicle approach notification device 100 shown in Fig. 1 in that the surrounding situation determination unit 150 is realized by a camera 152 and an image analysis unit 150C, and the switching control unit 140 is replaced by a switching control unit 140C. The camera 152 corresponds to the imaging means, and the image analysis unit 150C corresponds to the image analysis means.

[0046] One or more cameras 152 are installed at the front or sides of the vehicle, and capture images of the surroundings including at least the area in front of the vehicle. Based on images captured by the cameras 152, the image analysis unit 150C analyzes the positions and number of pedestrians and the like present around the vehicle, or the conditions around the vehicle, such as the width of the road on which the vehicle is traveling and the driving lanes.

[0047] The switching control unit 140C instructs the SP driving unit 130 to switch between the area W where the directional characteristics of the sound output from the speaker array 120 are narrow and the area N where the directional characteristics of the sound output from the speaker array 120 are wide, based on the situation around the vehicle analyzed by the image analysis unit 150C.

[0048] For example, as a result of analyzing the image, if there are many pedestrians around the vehicle, an area N for widening the directional characteristics is selected, and if there are no pedestrians around the vehicle, an area W for narrowing the directional characteristics is selected. This makes it possible to switch between wide and narrow directional characteristics of the radiated sound of the speaker array 120 after accurately grasping the surrounding situation. Note that the captured image may be analyzed and a process equivalent to that of the speed acquisition unit 150A shown in FIG. 9 may be performed, or a process equivalent to that of the driving environment determination unit 150B shown in FIG. 10 may be performed.

[0049] Fig. 12 is a diagram showing a modified example in which the directional characteristic of the speaker array 120 is changed according to the crowded state of the room. The announcement device 100D shown in Fig. 12 is installed, for example, in a sales floor of a department store, and emits a predetermined announcement sound to some customers. This announcement device 100D has a configuration similar to that of the vehicle approach notification device 100 shown in Fig. 1, and is different from the vehicle approach notification device 100 in that the surrounding situation determination unit 150 is realized by the crowded state determination unit 150D, the running sound generation unit 110 is replaced by the announcement sound generation unit 110D, and the switching control unit 140 is replaced by the switching control unit 140D. The announcement sound generation unit 110D corresponds to the output sound generation means, and the crowded state determination unit 150D corresponds to the crowded state determination means.

[0050] The crowded state determination unit 150D determines the crowded state of customers in the vicinity (a specific area in the department store). This determination may be performed by analyzing the image captured by the camera 152 as in the image analysis unit 150C shown in Fig. 11, or may be performed based on the detection result of a sensor installed at the entrance to detect the entrance and exit of customers.

[0051] Based on the surrounding congestion state determined by the congestion state determination unit 150D, the switching control unit 140D instructs the SP driving unit 130 to switch between selecting area W, where the directional characteristics of the announcement sound output from the speaker array 120 are narrow, and area N, where the directional characteristics of the announcement sound output from the speaker array 120 are wide.

[0052] For example, when it is quiet and there are few customers in a specific area, region N is selected to widen the directional characteristics of the radiated announcement sound in order to attract customers, and when it is busy and there are many customers in a specific area, region W is selected to narrow the directional characteristics of the radiated announcement sound so that only a certain number of customers can hear it. This makes it possible to switch between wide and narrow directional characteristics of the radiated sound of speaker array 120 depending on the surrounding congestion state.

[0053] 12 can be used for purposes other than announcement sounds in department stores. For example, in an art museum, when an exhibition room is crowded with many students during a student tour, area N that widens the directional characteristics of the radiated announcement sound is selected, and in other normal cases area W that narrows the directional characteristics of the radiated announcement sound is selected.

[0054] The present invention is not limited to the above embodiment, and various modifications are possible within the scope of the present invention. In the above embodiment, either a wide directional characteristic corresponding to the area N or a narrow directional characteristic corresponding to the area W is selected, but the area N and the area W may be alternately switched at a predetermined time to repeat the wide directional characteristic and the narrow directional characteristic of the radiated sound of the speaker array 120. This makes it possible to make the radiated sound of the speaker array 120 audible to both the near and far surrounding spaces.

[0055] In addition, in the above-described embodiment, the speaker array 120 is configured using the ultrasonic speaker 122, but the speaker array 120 may be configured using a speaker other than an ultrasonic speaker (a speaker that directly outputs sound in the audible band). [Industrial Applicability]

[0056] As described above, according to the present invention, by using speakers that are included in a narrow area from among the multiple speakers that make up the speaker array, the directional characteristics of the speaker array will be broadened, and by using speakers that are included in a wide area, the directional characteristics of the speaker array will be narrowed. Therefore, by switching the area in which the speakers are arranged, it is possible to switch the output range of the sound radiated by the speaker array. [Explanation of symbols]

[0057] 100, 100A, 100B, 100C Vehicle approach notification device 100D Announcement Device 110 Running sound generation unit 110D Announcement sound generator 120 Speaker Array 122 Speaker 130 SP (Speaker) drive unit 140, 140A, 140B, 140C, 140D Switching control unit 150 Surrounding situation judgment unit 150A speed acquisition part 150B Driving environment judgment unit 150C Image analysis section 150D Congestion state determination unit 152 Cameras

Claims

1. an output sound generating means for generating a sound to be output; a speaker array including a plurality of speakers to which the generated sound of the output sound generating means can be selectively input; a speaker switching means for switching one or more of the speakers to which the generated sound is input; a switching instruction means for instructing the speaker switching means to switch in accordance with the width or narrowness of the directional characteristics of the sound output from the speaker array; A speaker system comprising:

2. The speaker system according to claim 1, wherein the speaker switching means selectively switches between a first area having a large area and including a large number of the speakers and a second area having a small area and including a small number of the speakers.

3. A surrounding situation determination means is further provided for determining a surrounding situation, 3. The speaker system according to claim 2, wherein the switching instruction means issues a switching instruction based on the surrounding conditions determined by the surrounding conditions determination means.

4. A speaker system that is mounted on a vehicle and outputs a sound to notify people in the vicinity of the approach of the vehicle, the surrounding situation determination means is a speed acquisition means for acquiring a traveling speed of the vehicle, The speaker system according to claim 3, characterized in that the switching instruction means issues a switching instruction to select the first area so that the directional characteristic of the sound output from the speaker array becomes narrower when the driving speed acquired by the speed acquisition means is fast, and to select the second area so that the directional characteristic of the sound output from the speaker array becomes wider when the driving speed acquired by the speed acquisition means is slow.

5. A speaker system that is mounted on a vehicle and outputs a sound to notify people in the vicinity of the approach of the vehicle, The surrounding situation determination means is a driving environment determination means that determines whether the vehicle is traveling in an urban area or a suburban area, The speaker system according to claim 3, characterized in that the switching instruction means issues a switching instruction to select the first area so that the directional characteristic of the sound output from the speaker array becomes narrower when the driving environment determination means determines that the vehicle is traveling in a suburban area, and to select the second area so that the directional characteristic of the sound output from the speaker array becomes wider when the driving environment determination means determines that the vehicle is traveling in an urban area.

6. 3. The speaker system according to claim 2, wherein the switching instruction means issues a switching instruction to alternately select the first area and the second area.

7. The surrounding situation determination means includes an imaging means for imaging the surroundings, and an image analysis means for analyzing the surrounding situation based on an image obtained by the imaging means, 4. The speaker system according to claim 3, wherein the switching instruction means issues a switching instruction to select either the first area or the second area based on the surrounding conditions analyzed by the image analysis means.

8. The surrounding situation determination means is a congestion state determination means for determining a surrounding congestion state, 4. The speaker system according to claim 3, wherein the switching instruction means issues a switching instruction to select either the first area or the second area based on the surrounding congestion state determined by the congestion state determination means.

Images