JPS61200046A - Sound field corrector - Google Patents

Abstract

PURPOSE:To permit all the passengers to put into a regenerated sound field permitting the superior listening for the output sound of an audio apparatus by correcting the audio signals of the audio apparatus according to the level setting signal corresponding to the result of the detection for the fastening of seat belts. CONSTITUTION:Fastening detecting switches 13-16 which are turned-OFF on fastening are installed onto the connector parts 9a-12a for fastening seat belts 9-12. Front speakers 18 and 19 are installed at the right and left of a front tray 17, and rear speakers 21 and 22 are installed at the right and left of a rear tray 20. While, in a sound-field correcting apparatus, a level setting circuit 27 is connected to the other edges of the fastening switches 13-16. The level setting circuit 27 has four output terminals, and outputs, as digital signals, the value predetermined for each output terminal according to each input level supplied from the fastening detecting switches 13-16, and the audio signal of an audio apparatus is corrected.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a sound field correction device for correcting a reproduced sound field obtained by output sound through a plurality of channels of an audio device mounted on a transportation device.

When listening to music or the like using an audio device in a transportation device such as a vehicle, it is difficult for all passengers to listen to the output sound from the audio device in good condition because the seating positions of the passengers are fixed. For example, in-vehicle audio devices are sometimes provided with a sound field correction device that can arbitrarily change the localization of a reproduced sound field. However, in such sound field correction devices, there is usually an adjustment lever near the driver's seat that changes the localization of the reproduced sound field, so even if the adjustment lever is operated from the driver's seat, all passengers will not be able to enjoy the sound. It has been extremely difficult to obtain a reproduction sound field in which music and the like can be heard.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a sound field correction device that can obtain a reproduced sound field in which all passengers can relatively well hear output sounds from an audio device.

The sound field correction device of the present invention includes a fastening detecting means provided for each seat and detecting the fastening of the seat belt of that seat, a level setting means generating a level setting signal according to the output state of each fastening detecting means, The audio device is characterized in that it comprises a signal correction means that is provided in a supply line of at least one channel of audio signals to a speaker and corrects the audio signals in accordance with a level setting signal.

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows the interior of an automobile in which an audio device using the sound field correction device according to the present invention is mounted.

This automobile has 1 driver's seat, 2 passenger seats, and 3,404 left and right rear seats.

Each of the seats 1 to 4 is equipped with a seat belt 9 to 12, and the fastening connector portions 9α to 12α of the seat belts 9 to 12 are provided with fastening detection switches 13 to 16 that are turned off when the seat belts are fastened. There is. Further, front speakers 18 and 19 are provided on the left and right sides of the front tray 17 in front of the driver's seat 1 and passenger seat 2, and rear speakers 21 and 22 are provided on the left and right sides of the rear tray 20 behind the rear seats 3 and 4, respectively.

On the other hand, in the sound field correction device according to the present invention, as shown in FIG. 2, one end of the engagement detection switches 13 to 16 is grounded, and the voltage Vcc is supplied to the other end through resistors 23 to 26, respectively. Further, a level setting circuit 27 is connected to the other end of the fastening detection switches 13 to 16. The level setting circuit 27 has four output terminals, and each output terminal outputs a predetermined value as a digital signal according to each input level from the engagement detection switches 13 to 16. Each output terminal of the level setting circuit 27 is a D/A
It is connected via one of the (digital/analog) converters 28 to 31 to the control end of one of the VCAs (voltage controlled amplifiers) 32 to 35. VCA3
2 receives the left front channel audio signal of the 4 channels of audio signals in the audio device, VCA 33 receives the right front channel audio signal, VCA 34 receives the left rear channel audio signal, and VCA 35 receives the left rear channel audio signal. The right rear channel audio signal is supplied. Each of the outputs of the VCAs 32-35 is connected to a corresponding speaker 18, 19 via one of the power amplifiers 36-39 of the audio device.
21 or 22 are connected.

In the sound field correction device of the present invention having such a configuration, when any of the seat belts 9 to 12 is fastened at the collector portions 9α to 12α, the fastening detection switch (13 to 16) of the fastened seat belt is turned on. It turns off, and the level at the other end of the switch is reversed from low level to high level. The level setting circuit 27 has a built-in ROM in which a plurality of level data representing the setting levels of each of the four channels determined according to the number of passengers and their seating positions is written in advance as a data map, and is connected to the engagement detection switches 13 to 16. The level data corresponding to each input level is searched from the data map, and the searched level data is read out for each channel and the D of the corresponding channel is searched.
/A converters 28 to 31 as a level setting signal. Voltages corresponding to these level setting signals are applied from the D/A converters 28 to 31 to the corresponding VCAs 32 to 35.
Since the gain of each of the VCAs 32 to 35 becomes equal to the setting level of each channel represented by the level data retrieved by the level setting circuit 27. Therefore, since the gains of the power amplifiers 36 to 39 are at the same level, the speakers 18°19, 21, 22
The localization of the reproduced sound field obtained by the output sound of VCA 3
It is determined according to each gain of 2 to 35. That is, all the passengers at the seated positions of the passengers detected by the engagement detection switches 13 to 16 are connected to the speaker 1.
The localization of the reproduction sound field is determined so that the output sounds of 8, 19, 21, and 22 can be heard well.

In the above-described embodiments of the present invention, the case where the audio device is installed in a car has been described, but the present invention is not limited to this, and the present invention can also be applied to a case where the audio device is installed in a transportation device such as an airplane. It can be applied.

As described above, in the sound field correction device of the present invention, the fastening of the seat belt is detected for each seat, a level setting signal is generated according to the detection result of the fastening of each seat belt, and the audio is adjusted according to the level setting signal. The audio signal of the device is corrected. Therefore, since the number of passengers and their seating positions are determined from the detection results of the fastening of each seat belt, it is possible to create a reproduction sound field where all passengers can listen to music etc. well without operating adjustment levers etc. I can do it. In addition, since a good reproduction sound field cannot be obtained unless the seat belt is fastened, the driver is encouraged to fasten the seat belt, thereby improving safety while driving.

[Brief explanation of drawings]

FIG. 1 is a diagram showing the interior of an automobile in which an audio device using a sound field correction device according to the present invention is installed, and FIG. 2 is a block diagram showing an embodiment of the present invention. Explanation of symbols of main parts

Claims (1)

[Claims] A sound field correction device for correcting a reproduced sound field obtained by output sound through a plurality of channels of an on-board audio device in a transportation device having a plurality of seats each equipped with a seat belt, the sound field correction device being provided for each seat. fastening detection means for detecting fastening of the seat belt of the seat; level setting means for generating a level setting signal according to the output state of each of the fastening detection means; 1. A sound field correction device comprising a signal correction means provided in a supply line of the audio signal and correcting the audio signal according to the level setting signal.