JPH04336800A - Audio equipment mounted in vehicle - Google Patents

Abstract

PURPOSE:To provide optimum sound field space corresponding to the number of persons and the seating position of the person(s) in a car. CONSTITUTION:Plural speakers FL, FR, ML, MR, EL and ER are provided at positions different from one another in the car. DSP 4, 5, 61, 62 and 63 correcting parameters with respect to a digital audio signal and D/A converters 71, 72, and 73 performing the D/A conversion of the output signal of the DSPs and outputting an analog audio signal are provided. Plural sensors 12A to 12E detecting the number of persons and the seating positions of them, and a microcomputer 10 supplying detecting output of the sensors and controlling the DSPs are provided. The microcomputer 10 controls the processing characteristics of the DSPs based on the detection outputs of the sensors 12A to 12E, and corrects the parameters of the digital audio signal to generate the optimum sound field corresponding to the number of persons and their seating positions in the car.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle audio system.

0002

2. Description of the Related Art When the interior of an automobile is viewed as an audio space, its volume is much smaller than that of a general room or listening room. Additionally, the noise level is high due to the sound of cars running.

[0003] For this reason, unique standing waves or resonances tend to occur inside the automobile, and the reverberation time and other characteristics tend to have unique frequency characteristics.

[0004] Therefore, when an audio device is installed in a car, the speakers are arranged as shown in FIG. 6, for example. That is, FIG. 6 is a plan view showing the interior of a passenger car, in which speakers FL and FR are provided on the left and right front doors, and speakers BL and BR are provided on the rear deck.

[0005] Then, the speakers FL and FR are supplied with mainly direct audio signals, and the speakers BL and BR are supplied with direct audio signals.
Audio signals such as early reflected sounds and reverberant sounds are mainly supplied to the rear speakers BL and BR, and the early reflected sounds and reverberant sounds from the rear speakers BL and BR create a sense of spaciousness similar to that in an ordinary room. Alternatively, a surround effect is further added.

[0006] Furthermore, the level and reverberation time frequency characteristics of the audio signals supplied to the speakers FL to BR are corrected in advance so that the reproduced sound does not have any peculiar characteristics when it is reproduced as sound in the automobile. There is. Furthermore, the frequency characteristics and dynamic range of the audio signal are corrected, taking into account auditory loudness characteristics and masking effects, so that the desired music can be heard comfortably despite the noise inside the car.

[0007]

[Problem to be Solved by the Invention] However, even if the above-mentioned correction is performed, depending on the number of passengers and seat positions, the balance of the reproduced sound that the passengers actually hear may be significantly disrupted, resulting in inappropriate sound. The playback sound may be distorted.

For example, if the reproduced sound is corrected to be optimal for the driver in the front seat, for the passenger in the rear seat, the reverberant sound from the rear speakers BL and BR will be different from the front speaker FL. , the playback sound becomes too loud compared to the playback sound from the FR, resulting in an unnatural playback sound.

[0009] This invention solves these problems,
This allows optimal listening conditions to be satisfied according to the number of passengers and seat positions.

0010

[Means for Solving the Problems] Therefore, in the present invention, if the reference numerals of each part correspond to the embodiments described later, a plurality of speakers FL to BR provided at mutually different positions in an automobile, and a digital DSP4, 5, 6 that corrects parameters such as reverberation time for audio signals
1 to 63, D/A converters 71 to 73 that D/A convert the output signals of these DSPs 4, 5, and 61 to 63 to output analog audio signals, and audio from these D/A converters 71 to 73. Send signal to speaker FL~BR
a plurality of amplifiers 81 to 86, respectively, and a plurality of sensors 1 for detecting the number of occupants of the automobile and their seating positions.
2A to 12E, and a microcomputer 10 to which the detection outputs of the sensors 12A to 12E are supplied and which controls the DSPs 4, 5, and 61 to 63 is provided. The DSPs 4, 5, 61-63 control the processing characteristics of the DSPs 4, 5, 61-63, and adjust the parameters of the digital audio signal in accordance with the number of passengers and their seating positions to create the optimal sound field. This is a correction.

[0011]

[Operation] Sensors 12A to 1 detect the seating position and number of passengers.
2E, and based on this detection result, the DSP4
, 5, 61 to 63 are changed, and an optimal reproduction sound field is formed for the seating position and number of passengers at that time.

0012

[Embodiment] In FIG. 1, 1A to 1N indicate signal sources of audio signals such as an AM receiving circuit, an FM receiving circuit, a cassette tape player, and a CD player. The audio signals of the channels are taken out and these audio signals are supplied to the switch circuit 2.

[0013] Also, 3 is an A/D converter, 4, 5, 6
1 to 63 are DSP (digital signal processor)
, 71 to 73 indicate D/A converters. And D.S.
P4, 5, 61 to 63 perform audio signal processing as described later, such as adding reverberation components and correcting frequency characteristics.

Furthermore, 10 indicates a microcomputer for system control, and this microcomputer 10 is
It has data on programs to be executed in SP4, 5, 61-63 and parameters such as reverberation time, and various operation keys 11 and sensors 12A-12E are connected, and according to the outputs of keys 11 and sensors 12A-12E, Controls the processing characteristics of the DSPs 4, 5, 61-63.

[0015] In this case, the sensors 12A to 12E
is for detecting the number of passengers in a car and their seating positions. For this reason, the sensors 12A to 12E are configured by touch sensors or pressure sensors. For example, as shown in FIGS. 2 and 3, the sensor 12A
and 12B are provided in the driver's seat 91 and the passenger seat 92,
When a passenger is seated on these seats 12A, 12B, the seating is detected by contacting or pressing the waist or buttocks of the passenger.

Further, as shown in FIG. 2, the sensors 12C to 12E are similarly provided on the right side, center, and left side of the rear seat 93, and detect when each passenger in the rear seat 93 is seated. It is like that.

Furthermore, in this example, the speaker FL
In addition to ~BR, as shown in FIG. 2, rear door speakers ML and MR are provided on the left and right rear doors.

When the input switching key of the operation keys 11 is operated, the switch circuit 2 is controlled by the microcomputer 10, and the switch circuit 2 controls the signal sources 1A to 1A.
The audio signal from 1N is selected. Then, this selected audio signal is supplied to the A/D converter 3 and A/D converted into a digital audio signal, and this digital signal is converted from DSP4→DSP5→DSP61 to
63 in turn.

[0019] Then, the signal from the DSP 61 is transmitted to the D/A
The signal is supplied to a converter 71 and D/A converted into left and right channel analog audio signals, and these signals are supplied to speakers FL and FR through power amplifiers 81 and 82.

Further, the signal from the DSP 62 is supplied to the D/A converter 72 and D/A converted into left and right channel analog audio signals, and these signals are supplied to the speakers ML and MR through power amplifiers 83 and 84. The signal from the DSP 63 is sent to the D/A converter 73.
and is D/A converted into left and right channel analog audio signals, and these signals are sent to a power amplifier 85.
, 86 to the speakers BL and BR.

In this case, the DSPs 4, 5, 61-63 perform the following processing on the audio signal. That is, in the DSP 4, dynamic range correction is performed on the digital audio signal supplied to it, and in the DSP 5, level control and parametric equalizer processing (with band pass characteristics or band elimination characteristics, the center level and Corrections such as equalizer processing that changes the center frequency are performed. Further, in the DSPs 61 to 63, reverberation components and early reflected sound components are added.

[0022]The magnitude of parameters such as the reverberation time at this time is set by the microcomputer 10 based on the detection outputs of the sensors 12A to 12E.

That is, for example, sensors 12A to 12E
When the detection output indicates that a passenger is seated only in the driver's seat 91, the DSP 5 makes the signal level of the left channel higher than that of the right channel. In addition, in the DSP61, the amount of added reverberation components is reduced and the proportion of the direct sound signal is increased, and the DSP
In step 63, the amount of reverberation components added is increased to increase the proportion of signals of reverberation and early reflections. Further, the DSP 62 is located between the DSPs 61 and 63.

Therefore, when a passenger is seated only in the driver's seat 91, the volume of the left channel is made louder than that of the right channel, and the reproduced sound with a lot of direct sound is output from the speakers FL and FR, and the sound volume of the left channel is made larger than that of the right channel. , B.R.
Since reproduced sound with a lot of reverberation is output from the driver, an optimal sound field is created for the driver.

In this way, the balance between channels in the DSP 5 and the amount of reverberation components added in the DSPs 61 to 63 are controlled in accordance with the number of passengers and their seating positions indicated by the detection outputs of the sensors 12A to 12E. An optimal sound field is formed according to the seating position.

[0026] At this time, when a predetermined key of the keys 11 is operated, the DS
P5, parameters 61 to 63 are changed by a minute amount,
Therefore, by operating the keys, the inter-channel balance, reverberation time, etc. can be finely adjusted according to the user's preference.

Alternatively, when a predetermined key of the keys 11 is operated, the fact that the driver is seated in the driver's seat 91 is ignored or almost ignored, and a message is sent to the VIP seated in the rear seat 93. The signal level and reverberation components of each channel are changed to create the optimal sound field. That is, by operating the key 11, priority is given to the seat position.

[0028] Thus, according to the present invention, the DSP4,
5, 61 to 63 and speakers FL to BR to correct the acoustic characteristics or sound field characteristics inside the automobile, and sensors 12A to 12E are provided, and the detection outputs of the sensors 12A to 12E are transmitted to the DSP 4, 5, 61～
63, the audio signal is corrected in accordance with the number of passengers and their seating positions, so it is possible to automatically provide the optimal sound field to the passengers.

Moreover, as hardware, the sensor 12
All you need to do is add A~12E, and the sensor 12A~
Since 12E is also inexpensive, the cost increase is minimal.

[0030] Also, the sensors 12A to 12E are connected to the seats 91 to 12E.
93 and does not directly utilize the seat belt locking mechanism, there are no legal problems. Furthermore, the sensor 12
Even if A to 12E are added, wiring processing, equipment space,
This invention can be easily applied since it has little influence on other devices and automobiles.

FIG. 4 shows an example in which a sensor 12B for detecting a passenger in the passenger seat 92 is provided on the seat belt SB of the passenger seat 92. That is, in this example,
As also shown in FIG. 5, a sensor 12B is provided in the seat belt position adjustment part SBPA of the seat belt SB. In this case, this sensor 12B is constituted by a non-lock type push switch, and the lead wire 13 from the sensor 12B is constituted by a flexible substrate and is attached to the adjustment part SBPA with double-sided adhesive tape.

Therefore, in this example as well, there is no legal problem with the seat belt SB, and there is no problem when adjusting the length of the seat belt SB.

In the above description, in order to reliably detect that a passenger is seated, sensors are also provided on the backrests of the seats 91 to 93, and the detection outputs of these sensors and the detection outputs of the sensors 12A to 12E are An AND output with the output can also be used as a new detection output.

[0034]

[Effect of the invention] According to this invention, DSP4, 5, 61
63 and speakers FL to BR to correct the acoustic characteristics or sound field characteristics inside the automobile, and sensors 12A to 12E are provided.
By feeding back the detection outputs of A to 12E to the DSPs 4, 5, and 61 to 63, the audio signal is corrected according to the number of passengers and their seating positions, creating the optimal sound field for the passengers. can be provided automatically.

Moreover, as hardware, the sensor 12
All you need to do is add A~12E, and the sensor 12A~
Since 12E is also inexpensive, the cost increase is minimal.

[0036] Also, the sensors 12A to 12E are connected to the seats 91 to 12E.
93 and does not directly utilize the seat belt locking mechanism, there are no legal problems. Furthermore, the sensor 12
Even if A to 12E are added, wiring processing, equipment space,
This invention can be easily applied since it has little influence on other devices and automobiles.

[Brief explanation of drawings]

FIG. 1 is a system diagram of an example of the present invention.

FIG. 2 is a plan view showing an example of arrangement of speakers and sensors.

FIG. 3 is a perspective view showing an example of sensor arrangement.

FIG. 4 is a perspective view showing an example of sensor arrangement.

FIG. 5 is a perspective view showing an example of sensor attachment.

FIG. 6 is a plan view showing an example of arrangement of speakers.

[Explanation of symbols]

1A~1N Signal source 2 Switch circuit 3 A/D converter 4, 5 DSP 10 Microcomputer 11 Operation keys 12A to 12E sensor 61-63 DSP 71-73 D/A converter 81-86 Amplifier

Claims (1)

[Claims] Claim 1: A plurality of speakers installed at different positions in a car, a DSP that corrects parameters such as reverberation time for digital audio signals, and a D/A converter for the output signal of the DSP. A D/A converter that outputs an analog audio signal, a plurality of amplifiers that respectively supply audio signals from the D/A converter to the above-mentioned speakers, and a plurality of sensors that detect the number of occupants and seating positions of the automobile. and a microcomputer to which the detection output of the sensor is supplied and which controls the DSP, and the microcomputer controls the DS based on the detection output of the sensor.
An in-vehicle audio device that controls the processing characteristics of P and corrects parameters of the digital audio signal in accordance with the number of passengers and seating positions in the DSP so as to provide an optimal sound field.