JPH08179786A - On-vehicle stereophonic reproducing device - Google Patents

Abstract

PURPOSE: To provide an excellent and high grade stereophonic reproducing sound by measuring a sound field condition of a vehicle interior part by a simple means, and correcting a signal transmitting characteristic up to a listner from a program source. CONSTITUTION: When a mode switching device 12 is operated, a reproducing mode in a condition where amplifiers 5 and a musical sound signal reproducing device 6 are respectively connected to four loudspeakers 1, 2, 3 and 4 and a measuring mode of sending out a measuring signal by connecting a measuring signal generating device 7 to the loudspeaker in either one place, of receiving a sound by using the other loudspeakers as microphones, of obtaining a delay information signal by inputting its signal output to a delay time detecting device 8 and of correcting delay time and a frequancy characteristic of a reproducing time musical sound in an optimal condition by actuating a control device 9 and a filter device 14 by the delay information signal, can be simply switched to/from each other. Corresction control information on several kinds of representative vehicles can be preset in a storage device 13.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle-mounted stereo reproducing apparatus, which can provide a better acoustic condition at a listening position.
The present invention relates to a vehicle-mounted stereo reproducing device equipped with a measuring / calculating / controlling means, which enables quick correction and setting in a vehicle.

[0002]

2. Description of the Related Art A typical and simple structure of a conventional vehicle-mounted stereo reproducing apparatus is, as shown in FIG. 7, a left front speaker 1, a right front speaker 2, and a left front speaker 1, a left front speaker 2, and a left front speaker, respectively. A rear speaker 3 and a right rear speaker 4 are arranged, an amplifier 5 is connected to each of these speakers, and a music signal reproducing device 6 such as a tape deck is connected to each amplifier 5. In the vehicle-mounted stereo reproducing device having such a basic configuration, for example, in the driver's seat, the distance d1 between the listener 15 and the left front speaker 1 is more extreme than the distance d2 between the listener 13 and the right front speaker 2. It is very short, and when played normally, the difference in the propagation time from the left and right sound sources is large and a natural sound image localization cannot be obtained.Furthermore, due to the acoustic conditions of the transmission path and standing waves in the passenger compartment, etc. The frequency characteristics and phase characteristics of the reproduction signal spectrum change,
There was a drawback that it was impossible to hear a good reproduced sound.

In order to eliminate such drawbacks of the reproducing apparatus,
As shown in FIG. 8, a filter device 14 such as an FIR filter is inserted between the amplifier 5 and the music signal reproducing device 6,
The microphone 17 is set at the position of the listener 15 and the impulse signal is used to connect between the left front speaker 1 and the listener 15,
Between the right front speaker 2 and the listener 15, or between the listener 15 and the left rear speaker 3 and the right rear speaker 4 as necessary.
Means has been put into practical use for measuring the transfer characteristic between the first and second signals and adaptively controlling any one of the frequency characteristic, the arrival time difference and the impulse response of the reproduced acoustic signal by the filter device 14 based on the characteristic data.

[0004]

In the conventional vehicle-mounted stereo reproducing device having such a structure, first of all, in the basic structure shown in FIG. 6, as described above, from the speakers to the listening position. Since the acoustic conditions of the transmission paths are different, there is a drawback that not only natural sound image localization but also good reproduced sound cannot be heard.

The filter device 14 is inserted between the amplifier 5 and the music signal reproducing device 6, the microphone 17 is set at the position of the listener 13, and the transmission between the installed speakers and the listener 15 is performed. In the method of measuring characteristics and adaptively controlling any one of the frequency characteristics, arrival time difference and impulse response of the reproduced acoustic signal by the filter device 14 based on the characteristic data, the indoor size and speaker arrangement differ depending on the vehicle type. Therefore, re-measurement is required according to the vehicle type,
In all cases, it was not possible to obtain high quality playback sound.

Further, in the sound field, the problem of reverberation cannot be neglected even though it is in the passenger compartment. That is, since the interior volume of the passenger compartment is small, the reverberation time is short, and the value may differ from the generally recommended value for listening to music depending on the frequency. To compensate for this, a reverberation component in the target frequency band may be added by using a recursive filter, but the reverberation in each frequency band may be affected by the sound absorption performance of the interior materials used even in a passenger compartment with almost the same volume. The time will be different. The measurement of the average reverberation time in a room is complicated and difficult for general users.

Also, in any of the above problems,
The adaptive control method, which uses an external microphone 17 to measure the sound field condition, is a very complicated and difficult means for a general user because it requires the calculation processing of the measurement data. There was a problem called.

Therefore, the present invention solves the above-mentioned drawbacks of the prior art, and easily measures the transfer characteristics between the speaker position and the listening position without the need for an external microphone or measuring instrument, and listens. It is an object of the present invention to provide a vehicle-mounted stereo reproduction device that can quickly perform adaptive control of a better sound reproduction condition at a position.

[0009]

A vehicle-mounted stereo reproducing apparatus according to the present invention for achieving the above object will be described with reference to FIGS. 1 to 3 showing a first embodiment. A front left speaker 1, a front right speaker 2, a rear left speaker 3 and a rear right speaker 4, which are respectively arranged on the left and right sides, an amplifier 5 connected to each of the speakers, a music signal reproducing device 6, and a measurement signal generation. Device 7 and delay time detection device 8
A controller 9 for correcting the delay time and frequency characteristics of a music signal to be reproduced by operating the output of the delay time detector 8; and operating each speaker individually for reproduction or sound reception. In addition to switching the state, the speaker operation switching means 11 for connecting the preamplifier 10 to the speaker for sound reception and the music signal reproducing device 6 are connected via the amplifier 5 to each of the four speakers in total in front, rear, left and right. In the reproduction mode of the state, or while the measurement signal from the measurement signal generator 7 is applied to any one of the four speakers in total in the front, rear, left, and right, the other speakers are used for receiving sound. The output signal of the preamplifier 10 is input to the delay time detecting device 8, and the control device 9 is operated by the delay information signal obtained by the delay time detecting device 8, A vehicle-mounted stereo comprising: the speaker operation switching means 11 for switching to any of the measurement modes for correcting the delay time and frequency characteristics of a live music signal to an optimum state, and a mode switching device 12 interlocking with the speaker operation switching means 11. It is a playback device.

In the second embodiment, as shown in FIG. 4, a front left speaker 1, a front right speaker 2, a rear left speaker 3 and a rear right speaker 4 are arranged on the front and rear left and right sides of the passenger compartment, respectively. , An amplifier 5 connected to each of the speakers,
The music signal reproducing device 6, the measurement signal generating device 7, the delay time detecting device 8, and the delay time and frequency characteristics of the music signal which is operated and reproduced by the output of the delay time detecting device 8 are corrected to an optimum state. The control unit 9 and each of the speakers are individually switched between the operating state for reproduction or sound reception,
A speaker operation switching means 11 for connecting a preamplifier 10 to the sound receiving speaker, and a reproduction mode in which the music signal reproducing device 6 is connected to each of the four front, rear, left and right speakers via the amplifier 5. Alternatively, the measurement signal from the measurement signal generator 7 is applied to any one of the four front, rear, left and right speakers, and the other preamplifier 10 is used for receiving sound. Input signal to the delay time detecting device 8 and operate the control device 9 according to the delay information signal obtained by the delay time detecting device 8 to optimize the delay time and frequency characteristics of the music signal during reproduction. A mode switching device 12 interlocking with the speaker operation switching means 11 for switching to any of the measurement modes for correcting the state, and a typical vehicle of several types. Correction information Te is the car stereo reproducing apparatus characterized by comprises a storage device 13 which is preset.

As another embodiment, the one shown in FIGS. 5 and 6 is a front left speaker 1, a front right speaker 2, a rear left speaker 3 and a rear right speaker which are respectively arranged at the front and rear left and right in the vehicle compartment. 4, an amplifier 5 connected to each of the speakers, a music signal reproduction device 6, and a measurement signal generation device 7 for generating band noise having a 1 / N octave bandwidth.
Reverberation time detection device 18, average reverberation time calculation device that outputs a reverberation time control signal from the average reverberation time obtained by storing a plurality of reverberation times and the recommended reverberation time at the frequency stored in the storage device 13. 19, a reverberation adding device 20 that operates according to the output of the average reverberation time calculation device 19 to give an appropriate reverberation component to a reproduced music signal, and an operating state of each speaker for reproduction or reception. In addition to switching, the speaker operation switching means 11 for connecting the preamplifier 10 to the speaker for receiving sound, and the measurement signal generating device 7 to any one speaker for reproduction among the four speakers in total in front, rear, left and right. The band noise of 1 / N octave bandwidth from is applied.

At the same time, the output of the reverberation time detecting device 18 to which the output signal of the preamplifier 10 obtained from the speaker at another place for receiving sound is input is stored in the average reverberation time calculating device 19 and sequentially. The average reverberation time of the frequency band obtained by performing the same measurement process at different sound receiving points by the speaker operation switching means 11 is referred to the recommended reverberation time at the frequency stored in the storage device 13 to add the reverberation. Control means 9 for operating the device 20 to sequentially repeat the measurement process for determining the appropriate reverberation to the music signal at the time of reproduction in the frequency band for all frequency bands over the reproduction frequency band.
And a mode switching device 1 interlocking with the speaker operation switching means 11 for switching these measurement modes.
2 is a stereo reproduction device for a vehicle.

[0013]

In the vehicle-mounted stereo reproducing apparatus having such a structure, the speakers installed for reproduction are switched and used for receiving sound in measuring the transfer characteristics of the paths of the reproduced sound. There is no need to bring in a microphone, calculator, measuring instrument, etc. from the outside when measuring the acoustic conditions of.

By simply equipping the vehicle as a vehicle-mounted stereo reproduction device, the delay time between the respective speakers can be easily measured to estimate the size of the passenger compartment, and the delay time and the frequency characteristic that are the optimum conditions based on the result can be estimated. Can be corrected.

Correction information for operating the control device 9 is prepared in advance for a number of typical types of vehicles, and the correction information is preset in the storage device 13 to optimally reproduce the data without bothering the user. Can give way.

[0016]

1 is a block diagram showing the construction of a vehicle-mounted stereo reproducing apparatus according to the present invention. FIG.
In the figure, 16 is a schematic view of the vehicle. In the embodiment shown in the figure, a left front speaker 1 and a right front speaker 2 are attached to both front sides (inside surfaces of a front door) in a vehicle compartment, and a left rear speaker 3 and a right rear speaker 4 are attached to the back of a rear seat. There is. Reference numeral 15 represents a listener in the driver's seat.

The vehicle-mounted stereo reproducing apparatus according to the present invention has a reproducing mode for reproducing music and the like as a normal stereo reproducing apparatus, and one of the four speakers in total is a sound source for measuring acoustic conditions in the vehicle compartment. The output signal obtained by selectively receiving a speaker at another location as a microphone is input to the delay time detecting device 8, and the control device 9 is operated by the delay information signal obtained by the delay time detecting device 8.
Is activated to set the delay time and the frequency characteristic of the music signal at the time of reproduction to an optimum state, that is, two types of modes are set, and the mode switching device 12 allows the listener to select each mode. it can.

The left front speaker 1, the right front speaker 2, the left rear speaker 3 and the right rear speaker 4 arranged at the above four places, and an amplifier 5 connected to each speaker,
A music signal reproducing device 6 such as a CD player, a measurement signal generating device 7 included in a measuring system, a delay time detecting device 8 and a delay time and frequency of a music signal which is reproduced by operating the output of the delay time detecting device 8. A control device 9 that corrects the characteristics to an optimum state, and a speaker operation switching means 11 that selects and switches a speaker to be a microphone to connect to a preamplifier 10 are connected to each other via a mode switching device 12.

FIG. 2 is a connection diagram of the stereo reproducing apparatus of the present invention when the mode switching apparatus 12 is switched to the reproducing mode. An amplifier 5 for each channel is connected to each of the left front speaker 1, the right front speaker 2, the left rear speaker 3, and the right rear speaker 4, and a music signal reproducing device 6 is connected to each amplifier. It can be considered that the music signal reproducing device 6 means a well-known program source such as a CD player, a tape player, a tuner and the like.

FIG. 3 is a connection diagram of the stereo reproducing apparatus of the present invention when the mode switching device 12 is switched to the measurement mode. The measurement mode of this example corresponds to the case where the listener 15 is a driver, and the left front speaker 1 is selected as the reproduction speaker by the speaker operation switching means 11 that works in conjunction with the mode switching device 12, and the amplifier 5 and the control device are selected. It is connected via 9 to a measurement signal generator 7 that outputs, for example, an impulse. Further, of the remaining speakers, the right front speaker 2 closest to the listener 15 is also selected as the measurement microphone by the speaker operation switching means 11, and is connected to the delay time detection device 8 via the preamplifier 10.

The delay time detection device 8 has a built-in CPU together with a control device 9 which will be described later, and the output of the preamplifier 10 and the output signal of the measurement signal generation device 7 for comparison are applied to determine the delay time between the speakers. The size of the vehicle interior is calculated and estimated, and the estimated result is output to the control device 9.

The control device 9 calculates correction information relating to the optimum delay time, phase characteristic and frequency characteristic based on the delay time and transfer characteristic data input from the delay time detecting device 8 and inputs it to the filter device 14. Control the device.

The filter device 14 is connected between the music signal reproducing device 6 and the amplifier 5, and the delay time of the music signal is adjusted so that the reproduced sound from each speaker is in an optimum state based on the correction information from the control device 9. And phase characteristics and frequency characteristics are corrected.

In the second embodiment, the storage device 13 is incorporated, and the above-mentioned correction information regarding the relationship between the listening position and the speaker of each typical vehicle model is registered, and the vehicle is equipped with the present invention. When the stereo reproduction apparatus for use is installed, it has a feature that an optimum listening condition can be set without going through each measurement mode.

As another embodiment of the present invention, by expanding the functions of the constituent elements of the measuring circuit, the reverberation time in the passenger compartment can be corrected to an optimum value, and an excellent auditory effect can be imparted.

FIG. 5 is a flow chart showing the measurement procedure of this embodiment, and FIG. 6 shows the circuit configuration in the measurement mode of this embodiment obtained by operating the mode switching device 12. The configuration and operation of this embodiment will be described below with reference to both figures.

First, a front left speaker 1, a front right speaker 2, a rear left speaker 3 and a rear right speaker 4, which are respectively arranged on the front and rear left and right sides of a basic vehicle compartment, are connected to the respective speakers. The amplifier 5 and the music signal reproducing device 6 are the same as those in the first and second embodiments. Measuring signal generator 7
In this embodiment, the function is expanded so that band noise of 1 / N octave bandwidth is also generated. This 1 /
The band noise of N octave bandwidth is the most common measurement signal in the field of room acoustic measurement, together with the above-mentioned impulse.

Reference numeral 18 denotes a reverberation time detecting device, which detects the reverberation time at each measurement point, that is, the part of each speaker used for sound reception, and outputs it to the average reverberation time calculating device 19 in the next stage. Since the reverberation time detecting device 18 has a function of measuring the time taken for the reverberation sound to decay to a certain level after the signal sound is cut off at each measurement point, a part of the function of the delay time detecting device 8 can be expanded. Can be diverted.

This reverberation time is detected for a predetermined combination of speakers, and a plurality of reverberation times are input to the average reverberation time calculation device 19 to calculate the average reverberation time in the frequency band. The calculated average reverberation time is input to the control device 9 and converted by the reverberation adding device 20 into an instruction signal for adding reverberation.

The controller 9 is the average reverberation time calculator 1 described above.
9 is referred to, and the reverberation time information recommended in the frequency band previously stored in the storage device 13 is referred to, and the reverberation is appropriately added to the music signal at the time of reproduction in the frequency band. Convert it into information that determines the quantity.

The control device 9 has a function of outputting information for determining an appropriate reverberation addition amount for a music signal and also having a function of controlling a measurement procedure as described later.

Reference numeral 20 denotes a reverberation adding device, which has a function of giving an appropriate reverberation component to a music signal reproduced by being operated by the output of the average reverberation time calculating device 19. It may be expanded and incorporated in the device 14.

Thus, when the reverberation addition amount in one frequency band is set, the same measurement procedure is repeated in other frequency bands, and the reverberation time measurement and reverberation are performed for all frequency bands over the reproduction frequency band. The addition amount will be set, but this measurement procedure, that is, the setting of the combination of the reproduction speaker and the sound receiving speaker, the switching of the measurement signal band, the setting of the reverberation addition amount in each frequency band, etc. It is automatically controlled and performed by the control device 9.

The speaker operation switching means 11 and the mode switching device 12 have the same functions as in the first and second embodiments.

[0035]

[Effect] The vehicle-mounted stereo reproducing device according to the present invention has the following effects. In order to measure the transfer characteristics of each path of the reproduced sound, the speakers installed for reproduction are switched and used for sound reception.Therefore, when measuring the acoustic conditions inside the vehicle, use a microphone, calculator, measuring instrument, etc. No need to bring in from outside. Therefore, it is possible to easily set the optimum reproduction condition regardless of the place for the reproduction condition setting.

By simply equipping the vehicle as a vehicle-mounted stereo reproduction device, the delay time between the respective speakers can be easily measured to estimate the vehicle interior size, and the delay time and frequency characteristics that are optimal conditions based on the results can be estimated. Can be corrected. Therefore, a general user who is usually an amateur with respect to sound measurement can also hear a good reproduced sound similar to the reproduction condition setting by specialization.

The correction information for operating the control device 9 is prepared in advance for a typical number of types of vehicles, and the correction information is preset in the storage device so that the optimum reproducing method can be performed without bothering the user. Can be given. Therefore, depending on the vehicle, it is possible to eliminate the need to bother the user.

Regardless of the volume of the passenger compartment, acoustic conditions, etc.,
Since the optimum reverberation time is set over the entire reproduction band, an extremely excellent listening feeling can be obtained. Moreover, such a complicated acoustic measurement can be easily performed by general users.

Due to the above advantages, the transfer characteristic between the speaker position and the listening position and the reverberation time setting can be easily measured without the need for an external microphone or measuring instrument, and a better sound at the listening position can be obtained. The present invention has an effect that it is possible to provide a vehicle-mounted stereo reproduction device that can quickly perform adaptive control of reproduction conditions.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing a configuration of a vehicle-mounted stereo reproduction device according to a first embodiment of the present invention.

FIG. 2 is a connection diagram of a reproduction mode according to the first embodiment.

FIG. 3 is a connection diagram of a measurement mode according to the first embodiment.

FIG. 4 is a configuration diagram showing a configuration of a vehicle-mounted stereo reproduction device according to a second embodiment of the present invention.

FIG. 5 is a flowchart showing a measurement process of another embodiment.

FIG. 6 is a connection diagram of a measurement mode of another embodiment.

FIG. 7 is a configuration diagram showing a configuration of a conventional example.

FIG. 8 is an explanatory view of a sound field characteristic correcting means in a vehicle interior of a conventional example.

[Explanation of symbols]

 1 front left speaker 2 front right speaker 3 rear left speaker 4 rear right speaker 5 amplifier 6 music signal reproducing device 7 measurement signal generating device 8 delay time detecting device 9 control device 10 preamplifier 11 speaker operation switching means 12 mode switching device 13 storage device 14 Filter Device 15 Listener 16 Vehicle 17 Microphone 18 Reverberation Time Detection Device 19 Average Reverberation Time Calculation Device 20 Reverberation Addition Device

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Office reference number FI Technical display location H03H 21/00 8842-5J H04S 1/00 G 7/00 Z G10K 15/00 M

Claims (2)

[Claims] 1. A front left speaker 1, a front right speaker 2, and a rear left speaker 3 which are respectively arranged at the front and rear left and right in a vehicle compartment.
And the rear right speaker 4, the amplifier 5 connected to each of the speakers, the music signal reproducing device 6, the measurement signal generating device 7, the delay time detecting device 8 and the output of the delay time detecting device 8. Control device 9 for correcting delay time and frequency characteristics of a music signal that is operated and reproduced to an optimum state
And an operation state of each of the speakers is individually switched for reproduction or sound reception, and speaker operation switching means 11 for connecting a preamplifier 10 to the sound reception speaker, and the total of four speakers in front, rear, left and right, respectively. In the reproduction mode in which the music signal reproduction device 6 is connected via the amplifier 5, or the measurement signal from the measurement signal generation device 7 is supplied to any one of the four front, rear, left and right speakers. Is applied, and the output signal of the preamplifier 10 obtained as a sound receiving speaker at another location is input to the delay time detecting device 8, and the delay information signal obtained by the delay time detecting device 8 causes The speaker operation is switched off for operating the control device 9 to switch to any of the measurement modes for correcting the delay time of the music signal during reproduction and the frequency characteristic to the optimum state. Vehicle stereo reproduction apparatus characterized by comprising a mode switching device 12 for interlocking the example means 11. 2. A front left speaker 1, a front right speaker 2, and a rear left speaker 3 which are respectively arranged on the front and rear left and right sides in a vehicle compartment.
And the rear right speaker 4, the amplifier 5 connected to each of the speakers, the music signal reproducing device 6, the measurement signal generating device 7, the delay time detecting device 8 and the output of the delay time detecting device 8. A control device 9 for correcting the delay time and frequency characteristics of the music signal that is operated and reproduced to an optimum state;
Speaker operation switching means 11 for switching the operation state of each speaker individually for reproduction or sound reception and connecting a preamplifier 10 to the sound reception speaker, and the music for each of the four front, rear, left and right speakers in total. Signal reproduction device 6
Is connected via the amplifier 5, or the measurement signal from the measurement signal generator 7 is applied to any one of the four speakers in total in the front, rear, left and right, and other An output signal of the preamplifier 10 obtained by receiving a speaker at a location is input to the delay time detecting device 8, and the control device 9 is operated by the delay information signal obtained by the delay time detecting device 8 to reproduce. Mode switching device 12 which works in conjunction with the speaker operation switching means 11 for switching to any of the measurement modes for correcting the delay time and frequency characteristics of the music signal at time to the optimum state.
And a storage device 13 in which correction information for several typical types of vehicles is preset, an on-vehicle stereo reproduction device.