JPH03268700A - In-cabin sound filed controller - Google Patents

Abstract

PURPOSE:To attain excellent sound field reproduction by providing a control section switching a delay coefficient and a multiplier coefficient to a prescribed value simultaneously so as to allow proper listening to rear reflecting sound at a front seat and a rear seat. CONSTITUTION:When a seat selection button 305 is selected to a front seat mode, a control section 104 makes a delay coefficient of a delay device zero and makes a multiplier coefficient of each coefficient device identical to each other. Moreover, when the button 305 is selected to be in the rear seat mode, the control section 104 sets a delay coefficient of the delay device to T1sec and the multiplier coefficient of the coefficient device is set lower by AdB than that of the other coefficient device. In this case, the T1sec is a delay time of a sound wave equivalent to a distance between the front seat and the rear seat and the AdB is a difference of the sound pressure between the front seat and the rear seat when rear speakers 119, 120 are used as sounding sources. As a result, the sound image for both the front seat and the rear seat is located in the front center to each listener and the reproduction sound similar to that at the front seat is listened to.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a vehicle interior sound field control device for reproducing a desired sound field in the vehicle interior of an automobile.

BACKGROUND OF THE INVENTION In recent years, in-vehicle sound field control devices using digital signal processors have been developed to provide a sense of presence and spaciousness in a vehicle interior.

As a conventional vehicle interior sound field control device, for example, Japanese Patent Application Laid-Open No.
Publication No. 220599 and Journal of the Acoustical Society of Japan Vol. 45, No. 10, No. 78
6-793.

A conventional vehicle interior sound field control device will be described below.

Figure 6 shows the configuration of this conventional vehicle interior sound field control device, Figure 7 shows the arrangement of operation buttons on the operation unit, and Figure 8 shows an example of a reproduced signal with reflected sound added. shows. In FIG. 6, 601 is a reproduced acoustic signal source, 602 is an A/
The D converter 603 is a sound field control means, and the sound field control means 603 includes a left front reflected sound generation section 651, a right front reflected sound generation section 652, a left rear reflected sound generation section 653, and a right rear reflected sound generation section. It consists of 654.

The internal configuration of each reflected sound generation section is shown in FIG. In FIG. 2, 201, 202, 203, 204.degree. 205 are delay units, 208, 207, 208, 209.210 are coefficient units, and 211 is an adder. 655, 858, and 657 are adders. The control unit 604 is composed of a microcomputer, and controls the delay coefficients of each of the delay units 201 to 205 and the multiplication coefficients of each of the coefficient units 206 to 210 in the sound field control means 603 according to the operation of the operation unit 606, and displays the display unit 605. control the display of information. 607.60
8 is a D/A converter, 609, 610, 613, 614 is an amplifier, 615 is a left front speaker installed on the front left door, 616 is a right front speaker installed on the front right door, 619 is a rear tray. A left rear speaker 620 is provided on the left side, and a right rear speaker 620 is provided on the right side of the rear tray. In Figure 7, 701, 702, 703°7
04 is an operation button for selecting a desired reproduction sound field; for example, 701 is a normal mode in which no sound field is reproduced, 702 is a jazz club, 703 is a live house, and 704 is a concert hall. 705 is a display element of the display portion θ05.

Regarding the vehicle interior sound field control device configured as above,
The operation will be explained below.

The acoustic signal output from the reproduced acoustic signal source 601 is converted into a digital signal by the A/D converter 602 and inputted to the sound field control means 603, and the left channel direct sound and the right channel direct sound are added by the adder 655. It becomes a synthesized direct sound.

The synthesized direct sound is delayed by a desired time by delay devices 201 to 205 inside the left front reflected sound generation section 651, and each delayed signal is adjusted to a desired magnitude by coefficient multipliers 206 to 210.
The adder 211 synthesizes the left front reflected sound.

After the left front reflected sound is added with the left channel direct sound in an adder 656, it becomes the left front reproduction signal shown in FIG. 8(1). The left front playback signal is converted into an analog signal by a D/A converter 607 and amplified by an amplifier 609 to drive a left front speaker 615.

Similarly, the right front reflected sound is generated by the right front reflected sound generator 652 and added to the right channel direct sound by the adder 657 to become a right front reproduction signal, which drives the right front speaker 616.

Further, the synthesized direct sound is delayed by a desired time by delay units 201 to 205 inside the left rear reflection sound generator 653, each delayed signal is adjusted to a desired magnitude by coefficient units 206 to 210, and an adder 211 are combined to generate left rear reflection sound. The left rear reflected sound directly becomes the left rear reproduction signal shown in FIG. 8(2).

The left rear playback signal is converted to an analog signal by the D/A converter 608, amplified by the amplifier 613, and output to the left rear speaker 6.
19 is driven. Similarly, the right rear reflected sound is generated by the right rear reflected sound generator 654 and directly becomes a right rear reproduction signal, which drives the right rear speaker 620.

By selecting the operation buttons 701 to 704 of the operation unit 606, the control unit 604 displays the selected sound field on the display unit 605, and also displays the delay coefficients of the delay units 201 to 205 and the multiplication coefficients of the coefficient units 206 to 210. By changing the value to a preset value, it is possible to reproduce the sound field of a jazz club, concert hall, etc., for example.

Problems to be Solved by the Invention However, in the above-mentioned conventional configuration, (1) Generally, the magnitude and delay time of reflected sound are set so that a good sound field is reproduced when heard from the front seat; The desired sound field can be reproduced in the seats, but in the rear seats, the distance between the occupant's head and the rear speakers installed in the rear tray is very close, so the sound pressure of the rear reflected sound is high and the delay time is small. Appropriate back reflected sound cannot be heard and good sound field reproduction cannot be achieved.

(2) The forward signal for the rear seat occupants is the sound played from the front left and right door speakers, and since the distance from the speakers is farther than for the front seat occupants, the sound is blocked by the front seat and they can hear the appropriate forward playback sound. (3) In a vehicle interior, the reflection time of the room itself is much faster than in an ordinary room, so if you add reflected sound to an impulse-shaped music signal and play it back, the additional reflection When the number of sounds is limited, the direct sound and each reflected sound may be heard temporally separated, which may be unnatural. In such cases, conventional sound field control devices select another sound field with a short delay time for reflected sound, but this results in playback in a sound field different from the desired sound field. However, there was a problem in that the original function of the sound field control device could not be achieved.

The present invention solves the above-mentioned conventional problems. (1) With a simple operation, rear seat occupants can hear appropriate rear reflection sound in the same way as front seat occupants, and (2) Depending on the presence or absence of rear seat occupants. (3) Rear seat passengers can also hear appropriate forward playback sound; (4)
) An object of the present invention is to provide a vehicle interior sound field control device that can easily adjust reflected sound effects that can accommodate a variety of music sources.

Means for Solving the Problem In order to achieve this object, the vehicle interior sound field control device of the invention of claim 1 of the present application takes an acoustic signal as input, and performs delay processing on this input signal to obtain a forward reflected sound. A sound having a back reflection sound generation section which delays the input signal to obtain a back reflection sound like the sound generation section, a delay device connected to the output of the back reflection sound generation section, and a coefficient multiplier connected to the output of the delay device. The seat selection button includes a seat selection button provided on the operation section, and a control section that simultaneously switches the delay coefficient of the delay device and the multiplication coefficient of the coefficient device to predetermined values by selecting the seat selection button. .

Further, the vehicle interior sound field control device of the present invention according to claim 2 includes an infrared light emitting element provided on one door or side wall of a rear seat in the vehicle interior and an infrared light receiving element provided on the other door or side wall. The present invention is provided with a configuration in which the output of the rear seat occupant detection means constituted is used as a seat selection signal.

Further, a front reflected sound generation section which takes the acoustic signal of claim 3 of the present application as input and obtains a front reflected sound by delay processing the input signal, and adds the input signal and the output of the front reflected sound generation section to generate a forward reproduction signal. A first speaker for outputting a left channel signal of the front playback signal is installed on the door or side wall of the left side of the rear seat with its directivity axis aligned with the right passenger in the rear seat. A second speaker for outputting a right channel signal of a front playback signal is installed on the door or side wall of the right side of the rear seat with its directivity axis aligned with the passenger on the left side of the rear seat.

Further, the outputs of the front reflected sound generation section which receives the acoustic signal of Claim 4 of the present application and delays the input signal to obtain the front reflected sound, the rear reflected sound generation section which obtains the rear reflected sound, and the front reflected sound generation section. Selecting a reflected sound effect selection button and a reflected sound effect selection button provided on a sound field control means having a connected first coefficient multiplier and a second coefficient multiplier connected to the output of the rear reflected sound generation section, and an operation section. Accordingly, the control section simultaneously switches the delay coefficients of the front reflected sound generating section and the rear reflected sound generating section and the multiplication coefficients of the first coefficient multiplier and the second multiplier to predetermined values.

Effects The present invention has the above configuration, (1) When selecting a rear seat, the seat selection means is set in advance to reduce the magnitude of the rear playback signal and to increase the initial delay time of the rear playback signal. Appropriate rear reflection sound can be heard from the seats as well as from the front seats.

(2) When the rear seat occupant blocks infrared rays, the infrared rays are no longer input to the light receiving section, and the output state of the light receiving section changes, thereby enabling automatic detection of the rear seat occupant.

(3) On the left side of the rear seat, the distance from the right speaker is far, but the directivity matches, and although the distance from the left speaker is short, the directivity does not match, and as a result, the left and right sound pressures are almost the same. Similarly, on the right side of the rear seat, the left and right sound pressures are almost the same, allowing the rear seat to hear the appropriate forward playback sound.

(4) When selecting the high effect of the reflected sound effect selection means, by setting in advance to increase the magnitude of each reflected sound and increase the delay time of each reflected sound, the sound field can be reproduced assuming a large room. In addition, when the reflected sound effect selection means is selected to have a high effect, by setting in advance to reduce the magnitude of each reflected sound and the delay time of each reflected sound, it is possible to create a sound that is suitable for a small room. This makes it easy to adjust the effect of reflected sound.

EXAMPLE An example of the present invention will be described below with reference to the drawings.

FIG. 1 shows the configuration of the vehicle interior sound field control device according to the embodiment of the present invention, FIG. 2 shows the configuration of the reflected sound generation section, and FIG. 3 shows the arrangement of the operation buttons of the operation section. FIG. 4 shows the arrangement of speakers in the rear seats in the vehicle interior and the arrangement of the rear seat occupant detection means, and FIG. 5 shows an example of a reproduced signal to which reflected sound is added.

In FIG. 1, 101 is a reproduced acoustic signal source, 102 is an A
/D converter. The sound field control means 103 includes a front reflected sound generation section 151 and a right front reflected sound generation section 15.
2. Left rear reflected sound generation section 153, right rear reflected sound generation section 1
It consists of 54. The internal configuration of each reflected sound generation section is shown in FIG.

In Figure 2, 201, 202, 203, 204.2
05 is a delay device, 206, 207, 208°209.21
0 is a coefficient unit, and 211 is an adder.

155, 156, 157 are adders, 158, 159 are coefficient units, and 160 is a delay unit. A microcomputer 104 controls the delay coefficients of each of the delay units 201 to 205 and the multiplication coefficients of each of the coefficient units 206 to 210 in the sound field control means 103 by operating the operation unit 106, and also displays information on the display unit 105. Control what is displayed. 107.
108 is a D/A converter, 109. 110. 111
．． 112, 113, and 114 are amplifiers, 115 is a left front speaker provided on the front left door, 116 is a right front speaker provided on the front right door, and 117 is a left center speaker provided on the rear left door. The distance between the left center speaker 117 and the listening position on the rear left seat is set equal to the distance between the left front speaker 115 and the listening position on the front left seat. 118 is a right center speaker provided on the rear right door, and a left center speaker 11
The arrangement is symmetrical to 7. 119 is a left rear speaker provided on the left side of the rear tray, and 120 is a right rear speaker provided on the right side of the rear tray.

In FIG. 3, 301, 302, 303, and 304 are operation buttons for selecting a desired reproduction sound field. For example, 301 is a normal mode in which no sound field is reproduced, 302 is a jazz club, 303 is a live house, and 304 is a concert. Hall. 305 is a seat selection button, 306 is a reflected sound effect selection button, and 307 is a display element of the display section 105.

In FIG. 4, the left center speaker 117 is driven by the amplifier 111 of the left front reproduction signal. The right center speaker 118 is driven by the amplifier 112 of the right front reproduction signal. 401 is an infrared light emitting element of a rear seat occupant detection means provided on the rear left door located on the left side of the rear seat; 402 is an infrared light receiving element provided on the rear right door located on the right side of the rear seat; 403;
104 is a control section of the rear seat occupant detection means, and 104 is a control section of the sound field control means 103.

The vehicle interior sound field control device of this embodiment configured as described above is shown in FIGS. 1, 2, and 3 below.

The operation will be explained using FIGS. 4 and 5.

The acoustic signal output from the reproduced acoustic signal source 101 is converted into a digital signal by the A/D converter 102, and the sound field control means 1
03, and an adder 155 adds the left channel direct sound and the right channel direct sound to form a synthesized direct sound. The synthesized direct sound is generated by the delay device 2 inside the left front reflected sound generation section 151.
01 to 205, each delayed signal is adjusted to a desired magnitude by coefficient multipliers 206 to 210, and combined by adder 211 to generate left front reflected sound. The left front reflected sound is changed in size by a coefficient unit 158, and is then changed by an adder 15.
After being added with the left channel direct sound in step 6, Figure 5 (1)
The left front playback signal is shown in . Left front playback signal is D/A
Converter 107 converts it into an analog signal, and amplifier 109
The signal is amplified by the amplifier 111 to drive the left front speaker 115, and is amplified by the amplifier 111 to drive the left center speaker 117.

Similarly, the right front reflected sound is generated by the right front reflected sound generator 152, its magnitude is changed by the coefficient unit 158, and it is added with the right channel direct sound by the adder 157 to become the right front reproduction signal.
The right front speaker 116 is driven, and the right center speaker 118 is also driven.

Further, the synthesized direct sound is delayed by a desired time by delay units 201 to 205 inside the left rear reflection sound generator 153, each delayed signal is adjusted to a desired magnitude by coefficient units 206 to 210, and an adder 211 are combined to generate left rear reflection sound. The left rear reflected sound is delayed for a fixed time by a delay device 160, and its magnitude is changed by a coefficient multiplier 159, resulting in a left rear reproduction signal shown in FIG. 5(2). The left rear playback signal is D/A converter 1
The signal is converted into an analog signal at step 08, amplified by an amplifier 113, and driven to the left rear speaker 119. Similarly, the right rear reflected sound is generated by the right rear reflected sound generator 154, and the right rear reflected sound is generated by the delay unit 1.
The signal is delayed by a fixed time at step 60 and changed in magnitude by a coefficient multiplier 159 to become a right rear reproduction signal, which drives the right rear speaker 120.

By selecting one of the operation buttons 301 to 304 of the operation unit 106, the control unit 104 displays the selected sound field on the display unit 105, and also displays the delay coefficients of the delay units 201 to 205 and the coefficient units 206 to 210. By changing the multiplication coefficient to a preset value, it is possible to reproduce the sound field of a jazz club, concert hall, etc., for example. In this embodiment, the number of reflected sounds from each reflected sound generation section is five, but of course any number may be used.

Next, the operation of the seat selection button will be explained. Seat selection button 3
05 in the front seat mode, the control unit 104 controls the delay device 1.
The delay coefficient of 60 is set to zero, and the multiplication coefficients of coefficient multipliers 158 and 159 are made the same. In this case, the operation is the same as that of the conventional example. FIG. 5(2) shows the left rear reproduction signal when the front seat mode is set.

When the seat selection button 305 is set to rear seat mode, the control unit 10
4, the delay coefficient of the delay unit 160 is set to 11 seconds, and the multiplication coefficient of the coefficient unit 159 is compared with the multiplication coefficient of the coefficient unit 158.
Set to lower dB. Note that 11 seconds is the delay time of the sound wave corresponding to the distance between the front seat and the rear seat, and AdB is the sound pressure at the front seat and the sound pressure at the rear seat when the rear speaker 119.120 is the sound source. This is the difference. FIG. 5(3) shows the left rear playback signal when the seat selection button 305 is set to the rear seat mode.

With the above configuration, the seat selection button 305
If the sound pressure of the rear reflected sound at the front seat is RdB and the delay time from the rear speaker is Tr seconds, when the seat selection button 305 is set to the rear seat mode, the rear reflected sound is The level is set to AdB low (the delay time is increased by 11 seconds, but the distance to the rear speakers becomes smaller, so the sound pressure of the rear reflected sound in the rear seat is R-A+A=RdB, and the delay time is Tr+T1-T1= Tr seconds, and the sound pressure and delay time relative to the direct sound are almost the same for the rear reflected sound heard in the front seat in the front seat mode and the rear reflected sound heard in the rear seat in the rear seat mode.

As described above, according to this embodiment, by providing a seat selection button on the operation panel and setting the seat selection button to rear seat mode when listening in the rear seat, rear reflection sound almost the same in the rear seat as in the front seat is produced. It will be possible to listen.

Next, the operation of the rear seat occupant detection means will be explained. When either the left or right rear door is closed, the control unit 403 causes the infrared light emitting element 401 to emit light, and if there is no passenger in the rear seat, the light reaches the infrared light receiving element 402, and its output is input to the control unit 403. No rear seat occupant is detected. Conversely, if there is a passenger in the rear seat, the light is transmitted to the infrared receiving element 40.
2, the output is input to the control unit 403, the presence of a rear seat occupant is detected, and automatic detection of the rear seat occupant becomes possible. By inputting the output of the rear seat occupant detection means to the control unit 104 of the sound field control means as a seat selection signal, the operation of the seat selection button 305 can be made unnecessary.

As described above, according to this embodiment, by providing a rear seat passenger detection means using an infrared light emitting element, the rear seat mode is automatically set when riding in the rear seat without operating the rear seat selection button on the operation panel. is selected, eliminating complicated operations and erroneous operations.

Next, the operation of the rear door speaker will be explained. Fourth
As shown in the figure, the left center speaker 117 that outputs the left front playback signal has its directivity axis aligned with the rear seat right passenger, and its sound pressure directivity characteristics are the sound pressure at the rear right seat and the rear left seat. Set the sound pressures so that they are almost equal. Similarly, the right center speaker 118 that outputs a right front playback signal has its directivity axis aligned with the passenger on the left side of the rear seat, and its sound pressure directivity characteristics are the sound pressure at the right rear seat and the sound pressure at the left rear seat. Set so that they are almost equal. When an in-phase signal is supplied to the left center speaker 117 and the right center speaker 118 configured in this way, the sound pressure output from the left center speaker 117 and the sound pressure output from the right center speaker 118 are approximately equal in the rear right seat. The sound image will be localized in front of the rear right seat. Similarly, on the rear left seat, the sound pressure output from the left center speaker 117 and the sound pressure output from the right center speaker 118 are approximately equal, and the sound image is localized in front of the rear left seat. In addition, the front reproduced sound is heard from the left front speaker 115 and the right front speaker 116 in the front seat,
In the rear seat, left center speaker 117, right center speaker 118
Since the front seats and the rear seats hear almost the same sound from the front, the front seats and the rear seats hear almost the same sound played from the front.

As described above, according to this embodiment, by providing speakers with unique directivity in the rear door, the sound image for both the left and right seats in the rear is localized at the center in front of each listener, which is similar to that in the front seats. You can hear the sound from the front.

Next, the operation of the reflected sound effect selection button will be explained. When the reflected sound effect selection button 30B is selected to have a high effect, each reflected sound generation section generates the same reflected sound as in the conventional example. When the reflected sound effect selection button 306 is selected to have a small effect, the control section 104 controls the left front reflected sound generation section 151, the right front reflected sound generation section 152, the left rear reflected sound generation section 153, and the right rear reflected sound generation section in the sound field control means 103. Delay devices 201 to 205 inside each sound generation unit 154
Each of the delay coefficients is reduced to, for example, 1/2, and the multiplication coefficients of the coefficient multipliers 15B and 159 are further reduced to, for example, 1/2. FIG. 5(4) shows the left rear playback signal when the reflected sound effect selection button 306 is set to the small effect mode. With the above configuration, when the large effect of the reflected sound effect selection button 30B is selected, the loudness of each reflected sound is made thicker and the pitch of the delay time is set larger, thereby creating a sufficient sense of spaciousness. A sound field that simulates a large room can be reproduced. but,
If you play a music signal that contains impulse-like components in this state, the reflection time of the single room is short, so almost no reflected sound from the room itself is added, and you only hear the output from the sound field control device. If the number of reflected sounds that the sound field control device adds is limited, the direct sound and the reflected sound will be separated in time, creating an unnatural impression. In such a case, by selecting the small effect of the reflected sound effect selection button 306, the magnitude of each reflected sound is reduced, and at the same time, the pitch of the delay time is also reduced, thereby reproducing the sound field assuming a small room. Direct sound and reflected sound can be reproduced well without temporal separation.

As described above, according to this embodiment, a reflected sound effect selection button is provided on the operation panel, and the large effect mode is usually selected to create a sound field reproduction state assuming a large room with a sufficient sense of spaciousness. When playing music signals, select the small effect mode of the reflected sound effect selection button to create a sound field reproduction state assuming a small room where the direct sound and each reflected sound cannot be heard separately in time. This makes it easy to adjust the reflected sound effect to suit the reproduction of a variety of music sources.

Effects of the Invention As described above, the present invention provides a control unit that simultaneously switches the delay coefficient of the delay unit and the multiplication coefficient of the coefficient unit to predetermined values by selecting the seat selection button, so that the seat selection button can be used in both the rear seat and the front seat. In the same way, you can hear the appropriate back-reflected sound, and you can reproduce a good sound field.

In addition, the output of the rear seat occupant detection means, which is composed of an infrared light emitting element provided on one door or side wall of the rear seat of the vehicle interior and an infrared light receiving element provided on the other door or side wall, is used as the seat selection signal. By doing so, it becomes possible to automatically detect a rear seat occupant, and when riding in the rear seat, the rear seat mode is automatically selected, eliminating the complexity and erroneous operation of manual operations.

In addition, the first channel outputs the left channel signal of the forward playback signal.
A second speaker that outputs the right channel signal of the front playback signal is installed on the door on the left side of the rear seat, or on the side wall, with its directivity axis aligned with the passenger on the right side of the rear seat. Alternatively, by installing it on the side wall with the directional axis aligned with the passenger on the left side of the rear seat, the sound image for both the rear left and right seats will be localized to the center in front of each listener, allowing them to hear the appropriate forward playback sound, resulting in a good sound field reproduction. I can do it.

Furthermore, by selecting the reflected sound effect selection button, control is performed to simultaneously switch the delay coefficients of the front reflected sound generation section and the rear reflected sound generation section and the multiplication coefficients of the first coefficient unit and the second coefficient unit to predetermined values. By providing a section, normally the large effect mode is selected to create a sound field reproduction state assuming a large room with a sufficiently spacious feeling, and when playing an impulse music signal, the small effect mode of the reflected sound effect selection button is selected. By selecting the sound field to create a sound field reproduction condition that assumes a small room where the direct sound and each reflected sound are not heard separately in time, the reflected sound effect can be adjusted to suit the playback of a variety of music sources. With extremely easy selection operations, you can enjoy a sound field that is tailored to the situation inside the vehicle, and its practical effects are great.

[Brief explanation of drawings]

FIG. 1 is a block diagram of a vehicle interior sound field control device according to an embodiment of the present invention, FIG. 2 is an internal configuration diagram of a reflected sound generation section, and FIG. 3 is an arrangement diagram of operation buttons of an operation section of the same embodiment. Fig. 4 is a diagram showing the speaker arrangement in the rear seat of the vehicle interior and the arrangement of the rear seat occupant detection means of the same embodiment, Fig. 5 is a characteristic diagram showing an example of a reproduced signal of the same embodiment, and Fig. 6 is a diagram of the arrangement of the rear seats in the vehicle interior. FIG. 7 is a block diagram of the sound field control device, FIG. 7 is a layout diagram of operation buttons on the operation section, and FIG. 8 is a characteristic diagram showing an example of a conventional reproduction signal. 103...Sound field control means, 151...Left front reflected sound generation section, 152...Right front reflected sound generation section, 1
53... Left rear reflected sound generation section, 154... Right rear reflected sound generation section, 155, 156.157... Adder, 158, 159... Coefficient unit, 160.
...Delay unit, 104...Control unit, 105...
- Display section, 106... Operation section, 305... Seat selection button, 306... Reflected sound effect selection button, 401.
...Infrared light emitting element, 402...Infrared light receiving element,
403: Control unit for rear seat occupant detection means.

Claims (4)

[Claims] (1) A front reflected sound generation section which takes an acoustic signal as input and obtains a rear reflected sound by delay processing the input signal, and a rear reflected sound generation section which similarly delays the input signal and obtains a rear reflected sound; sound field control means having a delay device connected to the output of the reflected sound generation section and a coefficient device connected to the output of the delay device; a seat selection button provided on the operation section; and by selecting the seat selection button. A vehicle interior sound field control device comprising: a control section that simultaneously switches a delay coefficient of the delay device and a multiplication coefficient of the coefficient multiplier to predetermined values. (2) The output of the rear seat occupant detection means, which is composed of an infrared light emitting element installed on one door or side wall of the rear seat in the vehicle interior and an infrared light receiving element installed on the other door or side wall, is used as a seat selection signal. The vehicle interior sound field control device according to claim 1, characterized in that: (3) A rear reflected sound generation section that takes an acoustic signal as an input and obtains a rear reflected sound by delay processing the input signal in the same way as a front reflected sound generation section that delays the input signal and obtains a rear reflected sound; and the input signal. sound field control means having an adder that adds the signal and the output of the front reflected sound generating section to obtain a front reproduction signal; and a first speaker that outputs a left channel signal of the front reproduction signal, and a first speaker that outputs a left channel signal of the front reproduction signal. A second speaker that outputs the right channel signal of the front playback signal is installed on the door or side wall of the rear seat with its directivity axis aligned with the right-hand passenger in the rear seat, and a second speaker that outputs the right channel signal of the front playback signal is installed on the door or side wall of the rear seat right side of the rear seat. A vehicle interior sound field control device characterized by being installed with its directional axis aligned with the left passenger. (4) A front reflected sound generation section which takes an acoustic signal as input and obtains a rear reflected sound by delay processing the input signal, and a rear reflected sound generation section which similarly delays the input signal and obtains a rear reflected sound; a sound field control means having a first coefficient unit connected to the output of the reflected sound generation unit and a second coefficient unit connected to the output of the rear reflected sound generation unit; and a reflected sound effect selection button provided on the operation unit. and, by selecting the reflected sound effect selection button, the delay coefficients of the front reflected sound generation unit and the rear reflected sound generation unit and the multiplication coefficients of the first coefficient unit and the second coefficient unit are set to predetermined values. A vehicle interior sound field control device characterized by comprising a control section that switches at the same time.