JP2010245890A - In-vehicle speaker apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To achieve improvement of sound quality by optimizing places where speaker units are installed so that direct sound from the speaker units enters ears of a listener, and reducing a sound pressure difference between a pair of right and left speaker units. <P>SOLUTION: In an in-vehicle speaker apparatus, a pair of right and left speaker units 10 are installed, more forwardly than a driver seat and a front passenger seat, at a height being settled within a limited range 6 of vertically 7.25 cm on the basis of a lower end of each window, and the directions of the speaker units 10 are set so that direct sound from the speaker units 10 enters ears of a listener. Therefore, even without using speaker units having any particular structure, a sound pressure difference between right and left sides can be reduced, and direct sound surely enters ears of a listener 9, thereby improvement of sound quality can be achieved. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a vehicle-mounted speaker device including a plurality of speaker units installed in a vehicle such as a passenger car.

  The interior of passenger cars and other vehicles is limited in space, and seats, dashboards, console boxes, etc. are placed in narrow spaces, which is not a good environment for music playback.

  On the other hand, there are many people who enjoy music in the car, and a full-fledged in-vehicle audio system using a large-diameter speaker or a multi-channel speaker is also widespread.

  Examples of the installation location of the speakers in the car include an example in which a speaker having a relatively large aperture of about 15 cm is installed in the lower part of the door, an example in which the speaker is installed in the upper and lower parts of the dashboard, or around the lower end of the rear window. Are known. When a speaker is installed on the upper surface of the dashboard and the front surface of the speaker is directed upward, it is assumed that the reflected sound from the front window is actively used (see Patent Document 1).

  In addition to this, an example of installing a speaker for high frequency compensation at the top of the door, an example of installing a center speaker on the dashboard to emphasize a specific frequency range (for example, mid range), and a pillar between windows An example of installing a speaker has also been proposed (see Patent Document 2).

  In addition, an example has been proposed in which a small-diameter speaker is installed under the seat or the like and the sound pressure is improved by using a baffle effect such as a floor surface (see Patent Document 3).

Japanese Patent No. 2890764 Japanese Utility Model Publication No. 63-137045 JP 2006-5718 A

  When the front surface of the speaker is installed substantially parallel to the upper surface of the dashboard as in Patent Document 1, not the direct sound from the speaker but the reflected sound reflected from the front window enters the human ear in the car. There is a problem that the sound quality is not so good. Similar problems occur when speakers are installed at the bottom of doors and dashboards.

  Moreover, even when a speaker is installed in the pillar as in Patent Document 2, depending on the height at which the speaker is installed, there is a possibility that sound does not directly enter the human ear in the vehicle, and high-quality sound can be obtained. There is no guarantee.

  Further, even in the case of Patent Document 3, although the sound pressure can be improved, since the direct sound does not enter the human ear in the vehicle, the sound quality cannot be improved.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to optimize the installation location of the speaker unit so that direct sound from the speaker unit enters the listener's ear, and Another object of the present invention is to provide a vehicle-mounted speaker device that improves the sound quality by reducing the difference in sound pressure between the speaker portions.

In order to solve the above problems, one aspect of the present invention is installed at a height that falls within a restricted range of 7.25 cm above and below the lower end of at least one of the front window, the side window, and the rear window. A plurality of speaker units,
Among the plurality of speaker units, at least two speaker units that are paired on the left and right are installed in front of the driver seat and the passenger seat,
Provided is an in-vehicle speaker device in which an orientation of the speaker unit is set so that a direct sound from the two speaker units enters at least an ear of a listener seated in a driver seat and a passenger seat. Is.

  According to the present invention, in order to optimize the installation location of the speaker unit, more direct sound from the speaker unit enters the ear of the listener, and the sound pressure difference between the left and right speaker units is reduced, As a result, the sound quality is improved.

(A) is a figure explaining the installation place of the vehicle-mounted speaker apparatus which concerns on embodiment of this invention, (b) is an external view of a vehicle. The figure which looked at the listener seated in the driver's seat from the side. The figure which classifies the height of the range of 150 cm-190 cm for every 5 cm, and shows the result of having calculated AE of FIG. The figure which compared the length of D and E of FIG. 2 with height 150cm and height 190cm. The figure which showed the common part F typically. The bird's-eye view which looked at diagonally forward from the back seat side inside the car. The figure which shows the example which installed the speaker part 10 upright on the upper surface of the dashboard 8. FIG. (A) is a figure showing the example which has arranged microphone 11 in the front of speaker part 10, and (b) is the figure showing the example which has arranged the front of speaker part 10 in the direction different from microphone 11 by 90 degrees. The graph which shows the sound pressure measurement result of FIG. (A) is a graph which shows the sound pressure frequency characteristic of the speaker part 10 whose edge movable part outermost diameter is 40 mm, (b) is a graph which shows the sound pressure frequency characteristic of the speaker part 10 of 16 cm aperture. The bird's-eye view which shows an example of each of the left-right paired speaker part 10. FIG. The graph which shows the sound pressure frequency characteristic of the speaker part 10 of FIG. The figure which shows arrangement | positioning of the speaker in a vehicle.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  Fig.1 (a) is a figure explaining the installation place of the vehicle-mounted speaker apparatus based on embodiment of this invention. FIG. 1B is a developed view of the front window 2, the side window 3, and the rear window 4 in the vehicle 1.

  The speaker device according to the present embodiment includes a plurality of speaker units, and at least two of the speaker units that are paired on the left and right sides are installed in the passenger compartment ahead of the driver seat and the passenger seat, and more specifically. Is installed in the vehicle so as to be within a restricted range of 7.25 cm above and below with reference to at least one lower end 5 of the front window 2, side window 3 and rear window 4. In FIG. 1A, the limit range 6 is indicated by a broken line.

  As shown to Fig.1 (a), the position of the lower end part 5 of each window is not necessarily the same height. For this reason, the limit range 6 also slightly changes up and down. However, in the present embodiment, it is not assumed that a speaker having a caliber of the limit range of 6 will be installed, and it is borne in mind that a small-diameter speaker portion whose outermost diameter of the edge movable portion is about 40 mm is installed. ing. For this reason, even if the restriction range 6 slightly changes up and down, it is not always necessary to change the installation height of the speaker unit accordingly. In other words, the left and right pair of speaker units in the present embodiment have a certain degree of freedom with respect to the installation location as long as they are in a range in front of the driver's seat and the front passenger seat and within the limit range 6. Yes.

  Here, the basics of stereo reproduction in audio will be explained. When a sample is listened on the center line of a pair of speakers and the sound of the same volume is applied to the pair of speakers, the same sound pressure can be obtained in the ears of the sample listener. desirable.

  The greater the difference in sound pressure between the left and right speaker units that enters the ear of the listener, the more difficult it is to reproduce the sound image, and the listener cannot perceive a good sound. In order to reduce the difference in sound pressure as much as possible, it is necessary that the distance between the left speaker unit and the listener and the distance between the right speaker unit and the listener are the same.

  It has been found that the relationship between the sound pressure and the distance decreases in inverse proportion to the square of the distance. Considering this, the listener may be seated not only in the driver's seat but also in the passenger seat, so the sound pressure difference between the left and right speakers can be as large as possible. Smaller is desirable.

  In addition, it is desirable to arrange the speakers symmetrically from the center of the vehicle so that sound can be heard with the same sound quality at the left and right seats.

  For this reason, the distance between the listener and the left and right speakers is not the same, but it is desirable that the difference between the left and right distances is as small as possible because the sound pressure difference becomes smaller.

  Hereinafter, the reason why this embodiment provides the restriction range 6 as shown in FIG. FIG. 2 is a side view of the listener seated in the driver's seat.

  A horizontal line 5 in FIG. 2 indicates a lower end portion of the side window 3.

  First, the relationship between the height and the ratio of the length of each part of the human torso is calculated for a person with a height of 165 cm, and the length of each part of the torso is calculated for a person of 150 cm to 190 cm based on the ratio.

When the length of each part of the body is measured for a height of 165 cm and the ratio is calculated, it is as follows.
The ratio of the sitting height A to the height is 6/11, and A = height × 6/11.
The length B from the top of the head to the ear with respect to the sitting height is B = A / 6.
The length C from the ear to the shoulder with respect to the sitting height is C = A / 6.
The length D from the shoulder to the chest with respect to the sitting height is D = 2A / 9.
The length E from the chest to the seating surface with respect to the sitting height is E = 4A / 9.

  FIG. 3 is a diagram showing the results of calculating the above A to E by classifying heights in the range of 150 cm to 190 cm every 5 cm.

FIG. 4 is a diagram comparing the lengths of D and E with a height of 150 cm and a height of 190 cm. As shown in the figure, in D, there is a common part F having a height of 150 cm and a height of 190 cm. FIG. 5 is a diagram schematically showing the common portion F. FIG. This common part F is calculated by the following equation (1).
Common part F = (E with height 150 cm) + (D with height 150 cm) − (E with height 190 cm)
= 8.48 cm (1)

A seat lifter is usually installed in the seat of the vehicle, and the height of the seating surface can be adjusted. Assuming that the sheet lifter can move up and down by ± 3 cm, the common part F is calculated by the following equation (2).
Common part F = (E of height 150 cm + 3 cm) + (D of height 150 cm)
-(E-3cm height 190cm)
= 14.48 cm (2)

  As shown in FIG. 3, the height of the lower limit position of the common part F is equal to E = about 46 cm with a height of 190 cm. Therefore, the common part F has a height of 46 cm from the seating surface as a lower limit when considered from the standard seating surface position, and is about 14.5 cm from there.

  Next, the sound environment in the above-described areas A to E will be examined. The region on the lower side including the region E is located considerably below the ears of the listener, so that the direct sound from the speaker part does not easily enter the ears of the listener. In addition, there are many obstacles such as seats and console boxes, resulting in a sound with many reflections and absorptions, and a good sound cannot be obtained.

  The common part F has a height near the shoulder and mouth at a height of 150 cm. The region above this is a visible region that falls within the human visual field. When a speaker unit is installed in this region, it is limited to the pillar or ceiling between windows because of the empty space in the vehicle.

  Here, the acoustic characteristics when the speaker unit is attached above the region D and the region D will be verified. FIG. 6 is a bird's-eye view of the interior of the vehicle. In FIG. 2 and FIG. 6, four types of a, b, c, and d are assumed as installation locations of the speaker unit. In FIG. 6, the positions of the left and right speaker units are (a, a '), (b, b'), (c, c '), (d, d'). a is a boundary position between the front window 2 and the ceiling, and is assumed to be a position above the area B where the difference between the left and right sides is the smallest in front of the driver seat and the passenger seat. b is the center position of the pillar between the front window and the side window. The area B and the area C in FIG. 2 are occupied by the front window and the side window except for the pillar 7, and the speaker portion can be installed only in the central portion of the pillar 7.

  The speaker unit is located in front of the driver and passenger seats and symmetrically in the car, but the driver and passenger seats are biased to the left and right sides. The difference in sound pressure is small in an area where the distance from the driver's seat or the passenger seat is as long as possible, specifically, in the ceiling portion or near the boundary between the pillar and the ceiling between windows.

  For example, in FIGS. 2A and 2B, since one speaker unit is disposed at a position close to the driver's ear, the difference in distance between the left and right speaker units becomes large, and sound reproducibility is not good.

  C and d in FIG. 2 are lower end portions of the side window and the front window, and since there is a space for installing the speaker portion around this, the speaker portion can be easily installed.

  The lower end portion c of the side window is a position where the distance from the driver's ear can be taken the longest on the side window side, and if it is c, the distance difference between the left and right pair of speaker portions can be reduced and the sound pressure difference can also be reduced. .

  On the other hand, the lower end portion d of the front window has a sufficient space for installing a pair of left and right speakers, and the distance from the driver's ear can be long. Actually, since the distance from the driver's ear is longer in d than in c, the distance difference between the left and right speaker units can be further reduced.

  In summary, the distance difference between the listener and the speaker is small in the order of | a'-a |> | b'-b |> | c'-c |> | d'-d | in FIG. Become. That is, the sound pressure difference decreases in the order of a> b> c> d.

  As described above, since the listener can obtain good quality sound when the sound pressure difference between the left and right is smaller, d has the best sound reproducibility among a to d in FIG. It is. Both c and d are located within the range of region D in FIG.

  D in FIG. 2 is a length from the shoulder of the listener to the chest, and in a normal vehicle, the height of the center line of D substantially matches the lower end of the window. As mentioned above, the length of D also changes depending on the height of the listener's back, and when the height in the range of 150 cm to 190 cm is taken into consideration, the common part of D has a lower limit of 46 cm from the seating surface. And within the range of 14.5 cm. That is, even if the height changes, the range of 14.5 cm is a common part of D. Therefore, it can be considered that the lower end of the window is positioned at the height of the center line within the range of 14.5 cm.

  In the present embodiment, a range of 7.25 cm above and below the lower end of the window is set as a limit range 6 indicated by a broken line in FIG. The reason why the range of 7.25 cm above and below is set as the limit range 6 is that the distance between the ear of the listener and the speaker unit can be secured relatively large, and the sound pressure difference between the pair of left and right speaker units can be reduced. If the region B or C closest to the ear is set as the restriction range 6, the distance between the listener's ear and the speaker unit is shortened, and as described above, the difference in sound pressure between the left and right speaker units is increased, and the quality is improved. I can't hear the sound.

  In terms of increasing the distance between the listener's ear and the speaker unit, it is preferable to install the speaker unit in the region E rather than the region D, but the region E is considerably below the listener's ear. It is difficult for the direct sound from the speaker unit to enter the ear of the listener.

  As described above, in the present embodiment, the lower end of the window is set to a height that satisfies both requirements of reducing the sound pressure difference between the pair of left and right speakers while allowing more direct sound from the speakers to be heard. The range of 7.25 cm above and below with respect to the above was selected as the limit range 6 in which the speaker unit can be installed.

  However, even within the limit range 6, if the front surface of the speaker unit is formed substantially parallel to the upper surface of the dashboard, the sound from the speaker unit is radiated upward and reflected by the front window 2, The reflected sound enters the listener's ear. In this case, the direct sound does not enter the listener's ear, and improvement in sound quality cannot be expected.

  Therefore, when the speaker unit 10 is installed on the upper surface of the dashboard as shown in FIG. 7, it is desirable to dispose the front surface of the speaker unit 10 by tilting from the upper surface direction of the dashboard. Thereby, the ratio that the direct sound from the speaker unit 10 enters the ear of the listener increases.

  FIG. 7 shows an example in which the speaker unit 10 is installed upright on the upper surface of the dashboard 8, but this is only an example. For example, a recess is formed in the dashboard 8, and at least a part of the speaker unit 10 is obliquely embedded in the recess so that the speaker unit 10 does not protrude upward from the upper surface of the dashboard 8. The direct sound may enter the ear of the listener 9.

  Inclining the front surface of the speaker unit 10 from the upper surface direction of the dashboard 8 means that the front surface of the speaker unit 10 and the upper surface of the dashboard 8 cannot be flush with each other. Therefore, it is considered that the speaker unit 10 is not a factor that impairs the design unity and aesthetics of the dashboard 8.

  Note that the speaker installation location is not necessarily limited to the upper surface of the dashboard 8. For example, as shown at positions c and c ′ in FIGS. 2 and 6, it may be provided near the base of the pillar 7 between the front window 2 and the side window 3. In this case, the pair of left and right speaker units 10 can directly input sound into the ear of the listener 9 even if the outer surface of the pillar 7 and the front surface of the speaker unit 10 are flush with each other.

  Therefore, the speaker unit 10 does not protrude from the outer surface of the pillar 7, the presence of the speaker unit 10 becomes inconspicuous, is desirable in terms of design, and is suitable as a speaker installation position because it is a position where direct sound can be delivered to the ear. It can be said that it is a good position.

  The present inventor conducted an experiment shown in FIG. 8 in order to examine how the direct sound entering the listener's ear changes depending on the direction of the speaker. 8A is a diagram illustrating an example in which the microphone 11 is disposed in front of the speaker unit 10, and FIG. 8B is a diagram illustrating an example in which the front surface of the speaker unit 10 is disposed in a direction different from the microphone 11 by 90 degrees. is there.

  FIG. 9 is a graph showing the sound pressure measurement results of FIG. 8, where the curve c1 shows the characteristics of FIG. 8 (a) and the curve c2 shows the characteristics of FIG. 8 (b).

  The curve c1 has a higher sound pressure up to the high frequency band than the curve c2, and indicates that when the microphone 11 is arranged in front of the speaker unit 10, more direct sound enters the microphone 11.

  From the results of FIG. 9, it can be seen that when the speaker unit 10 is installed, it is desirable to install the speaker unit 10 so that the front surface of the speaker unit 10 faces the listener as much as possible.

  FIG. 10A is a graph showing the sound pressure frequency characteristic of the speaker unit 10 having an outer edge diameter of 40 mm, and FIG. 10B is a graph showing the sound pressure frequency characteristic of the speaker unit 10 having a 16 cm aperture.

  Curves c3, c4, and c5 are shown in FIGS. 10 (a) and 10 (b), respectively. Curve c3 is an example in which the microphone 11 is placed directly in front of the speaker, curve c4 is an example in which the microphone 11 is placed 30 degrees away from the front of the speaker, and curve c5 is an example in which the microphone 11 is placed 60 degrees away from the front of the speaker. Each is shown.

  In the case of the speaker unit 10 having an edge movable portion outermost diameter of 40 mm, the sound pressure is maintained at both 0 degrees and 30 degrees up to about 12 kHz. On the other hand, in the case of the speaker unit 10 having a 16 cm aperture, the sound pressure at 30 degrees starts to decrease from around 4 kHz as compared with the sound pressure at 0 degrees.

  Thus, it can be seen that the speaker unit 10 having the outermost diameter of the edge movable unit having a diameter of 40 mm has a broadband directivity than the 16 cm aperture.

  Based on the result of FIG. 10, in the present embodiment, the speaker unit 10 having an outermost diameter of the edge movable unit capable of obtaining broadband directivity is 40 mm. Note that if the speaker unit 10 has an outermost outer diameter of the edge movable part of 40 mm or less, the sound pressure frequency characteristic as shown in FIG. 10A can be obtained. Therefore, the outermost diameter of the edge movable part is not necessarily limited to 40 mm. .

  FIG. 11 is a bird's eye view showing an example of each of the pair of left and right speaker units 10. As shown in the figure, each speaker unit 10 includes two speaker bodies 12 and a passive radiator 13. The reason why the two speaker units 10 are provided is to increase the sound pressure and increase the power. Note that the number of speaker units 10 is not limited to two, and may be one or three or more.

  The passive radiator 13 is for compensating for the low frequency range. Instead of providing the passive radiator 13, a bass reflex method may be employed, or a sealed speaker unit 10 that does not particularly perform low-frequency compensation may be employed.

  FIG. 12 is a graph showing the sound pressure frequency characteristics of the speaker unit 10 of FIG. As described above, the pair of left and right speaker units 10 are installed in front of the driver's seat and the front passenger seat, and at a height within a limit range 6 of ± 7.25 cm above and below with reference to the lower end of each window.

  Recently, a multi-channel acoustic system using three or more speaker units 10 is often employed. Therefore, a multi-channel configuration can also be adopted in this embodiment.

  In this case, for example, as shown in FIG. 13, in addition to the left and right pair of speaker units 10 described above, the pillars 14 beside the driver seat and the passenger seat, that is, between the front side window 3 and the rear side window 3. The left and right speaker units 10 may also be disposed on the pillars 14.

  In this case, it is desirable that the installation height of the speaker unit 10 is set within the limit range 6 described above. As a result, the left-right distance difference with the listener seated in the second or third row can be reduced to some extent, and the left-right sound pressure difference can be made relatively small.

  Further, by installing the speaker unit 10 at a height within the restricted range 6, direct sound can easily enter the ears of the listener.

  Furthermore, by setting the speaker aperture to be installed in the pillar 14 so that the outermost diameter of the edge movable portion is 40 mm or less, the sound pressure can be maintained high in a wide band, and sound reproducibility is improved.

  The arrangement of the speaker unit 10 shown in FIG. 13 is an example, and the speaker unit 10 may be arranged behind the pillar between the rear side window 3 and the rear window 4 or the rear seat.

  Thus, in the present embodiment, the pair of left and right speaker units 10 are installed in front of the driver's seat and the passenger seat, and at a height within a limit range 6 of ± 7.25 cm above and below with respect to the lower end of each window. In addition, since the direction of the speaker unit 10 is set so that the direct sound from the speaker unit 10 enters the ear of the listener 9, the difference in sound pressure between the left and right can be reduced without using the speaker unit 10 having a special structure. In addition, the direct sound can surely enter the ear of the listener 9 and the sound quality can be improved.

  The aspect of the present invention is not limited to the individual embodiments described above, and includes various modifications that can be conceived by those skilled in the art, and the effects of the present invention are not limited to the contents described above.

  That is, various additions, modifications, and partial deletions can be made without departing from the concept and spirit of the present invention derived from the contents defined in the claims and equivalents thereof.

DESCRIPTION OF SYMBOLS 1 Vehicle 2 Front window 3 Side window 4 Rear window 6 Restriction range 7 Pillar 8 Dashboard 10 Speaker part 11 Microphone 12 Speaker main body 13 Passive radiator

Claims (6)

A plurality of speaker units installed at a height that falls within a restricted range of 7.25 cm above and below the lower end of at least one of the front window, side window, and rear window;
Among the plurality of speaker units, at least two speaker units that are paired on the left and right are installed in front of the driver seat and the passenger seat,
An in-vehicle speaker device characterized in that an orientation of the speaker unit is set so that direct sound from the two speaker units enters at least an ear of a listener seated in a driver seat and a passenger seat.   The in-vehicle speaker device according to claim 1, wherein an outermost diameter of the edge movable portion of the speaker portion is 40 mm or less.   The in-vehicle speaker device according to claim 1, wherein the speaker unit is provided in at least one of a dashboard and a pillar between a front window and a side window.   4. When the two speaker units that form the left and right pairs are installed along the upper surface of the dashboard, the front surfaces of the speaker units are installed so as to be inclined from the upper surface direction of the dashboard. The in-vehicle speaker device described.   The in-vehicle use according to claim 3, wherein when the two speaker units that form the left and right pairs are installed on the pillar, the front surface of the speaker is installed so as not to protrude from the outer surface of the pillar. Speaker device.   At least one of a pillar between the front side window and the rear side window and a pillar between the rear side window and the rear window is at least a pair of left and right separate from the two speaker units. 6. The speaker device according to claim 1, wherein two speaker units are installed.

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