JPH03210900A - Acoustic reproducing device - Google Patents

Abstract

PURPOSE:To obtain a sense of spread with sufficient sound and presence by providing a detection means detecting whether or not sound field control is selected and a directivity change means changing the directivity of a speaker in response to the result of detection by the detection means and changing the propagation distance of sound till the listening position. CONSTITUTION:Three operation modes as high fidelity, casual and funky are set to an acoustic reproducing device 2. when the high fidelity mode is selected, speaker boxes 11L, 11R are directed upward to prevent the presence of sound image from being directed backward and the rear sound is reached to the listening position by a reflection sound. Moreover, when the casual mode is selected, a digital signal processor 5 is set and a reverberation sound with a comparatively longer delay time is added and the speaker boxes 11L, 11R are directed upward. Moreover, when the funky mode is selected, the reverberation sound with a comparatively short delay time is generated and the speaker boxes 11L, 11R are directed horizontal.

Description

[Detailed Description of the Invention] Overview When sound field control is selected in a car-mounted sound reproduction device, etc., the speaker box is angularly displaced, etc. hand,
Increase the propagation distance of sound to the listening position.

By arranging a speaker device capable of driving angular displacement as described above behind the listening position, and arranging a fixed speaker whose pointing direction does not change in front of the listening position, when sound field control is selected, Because the sound from the rear speakers reaches the listening position later than the sound from the front speakers, it is possible to expand the sound field and reproduce sound with a sense of presence that could not be expressed through computational processing. can.

INDUSTRIAL APPLICATION FIELD The present invention relates to a sound reproduction device suitably implemented in a vehicle-mounted sound reproduction device or the like.

Conventional technology In recent years, digital processing technology for audio signals has progressed, and sound field control devices have been proposed that use so-called digital signal processors to configure an optimal sound field depending on the type of music being played. . When this sound field control device is used, for example, in a car, speakers are arranged on the front left and right sides, the front center, and the rear left and right sides of the listening position, and the digital signal processor is used to control early reflected sounds and reverberations. Sound is created by processing the sound, and the sound thus created is added to the direct sound and converted into sound from the speakers arranged at each of the positions, corresponding to the sound field to be reproduced. In this way, it is configured to reproduce sound with a wide range.

Problems to be Solved by the Invention In the prior art as described above, the front speaker and the rear speaker reproduce the same reflected sound created by the digital signal processor, so the reproduced reflected sound is They cancel each other out near the listening position, so there is a limit to the sense of spaciousness and realism that can be expressed using only the arithmetic processing of a digital signal processor.

An object of the present invention is to provide a sound reproduction device that can provide a sufficient sense of sound expansion and presence.

Means for Solving the Problems The present invention provides a sound field control means for controlling a sound field by processing an acoustic signal from an acoustic signal source, and converting the sound signal processed by the sound field control means into sound. a speaker; a detection means for detecting whether the sound field control is selected; and a directionality for changing the direction of the speaker and changing the propagation distance of sound to the listening position in response to the detection result of the detection means. A sound reproducing device characterized by including a direction changing means.

Further, the present invention is characterized in that the pointing direction changing means is a driving means for driving a speaker box in which the speaker is housed to angularly displace it.

According to the present invention, the acoustic signal from the acoustic signal source is given to the speaker via the sound field control means to be made into a sound, and when the sound field control is selected, the sound field control means It processes acoustic signals to create early reflected sounds and reverberant sounds, and adds these sounds to direct sound and outputs them.

Further, the detection means detects whether the sound field control means is performing the arithmetic processing, that is, whether the sound field control is selected. The detection result of the detection means is given to a pointing direction changing means, and the pointing direction changing means changes the propagation distance of the sound to the listening position by angularly displacing the speaker box in which the speaker is housed. Therefore, for example, by setting the direction of the speakers in front of the listening position as the direction of the listening position, and making the direction of the speakers in the rear side upward, the reflected sound created by the above calculation process will not be reflected from the front speakers. , directly reaches the listening position, and reaches the rear speaker after being reflected from, for example, the ceiling.

In this way, by setting the propagation distances of the reflected sounds to be different from each other, it is possible to obtain a sense of spaciousness and presence that cannot be obtained through arithmetic processing.

Embodiment FIG. 1 is a block diagram showing the electrical configuration of a vehicle-mounted sound reproduction device 2 according to an embodiment of the present invention, and FIG. 2 is a perspective view of a speaker device 1 used in the sound reproduction device 1. .

The left and right channel sound signals from the sound signal source 3, such as a magnetic tape playback device or compact disk playback device, are separated into front left and right, front center, and rear left and right sound signals by the balance/fade adjustment section 4, Analog/digital converter ADFL, ADFR, ADFC; AD
It is converted into a digital signal by RL and ADRR and input to the digital signal processor 5.

An input operation section 6 is provided in association with the digital signal processor 5, which is a sound field control means and a detection means.
In response to input operations from the controller, it adds early reflections and reverberations, as will be described later, and performs delay processing.

Each output from the digital signal processor 5 is connected to a digital/analog converter DAFL, DAFR.

After being converted into analog audio signals by DAFC, DARL, and DARR, power amplifiers AFL and APR are used.

Each speaker 5PFL via AFC, ARL, ARR
, 5PFR, 5PFC, 5PRL, and 5PRR, and are acousticized.

In the vehicle compartment 7, there is a speaker 5PF on the front left side.
L is placed, and the speaker 5PPR is placed on the front right side! A speaker 5PFC is arranged at the center of the front, a speaker 5PRL is arranged at the rear left, and a speaker 5PRR is arranged at the rear right. Center speaker 5PF
The sound from C is reflected by the front glass 8 and radiated into the vehicle interior 7. Further, the speakers 5PRL and 5PRR are integrated into the speaker device 1.

The digital signal processor 5 drives the drive mechanism 10 of the speaker device 1 via the drive circuit 9 in response to an input operation from the input operation section 6, and drives each of the speakers 5PRL.
, 5PRR respectively.Speaker box 1
Adjust and control the elevation angles of 1L and 11R.

This sound reproduction device 2 includes, for example, a high-fidelity device.

There are three operating modes: casual and funky. When the high-fidelity mode is selected, the digital signal processor 5 is turned off and the balanced
The output from the fade adjustment unit 4 is directly transmitted to the power amplifiers AFL, AFR, AFC, and ARL by a configuration not shown.
, is input to ARR. At this time, since sound is directly emitted from the rear speakers 5PRL and 5PRR, the speaker boxes 11L and IIR are oriented upward to prevent the sound image from being localized to the rear side. The sound reaches the listening position as a reflected sound.

Further, when the casual mode is selected, the digital signal processor 5 is turned on.

Reverberation sound with a relatively long delay time is added, assuming a concert hall or the like where there is almost no sound reflected from the floor and much sound reflected from the walls and ceiling, and the speaker boxes IIL and IIR are directed upward.

Furthermore, when funky mode is selected,
A reverberation sound with a relatively short delay time is created, assuming a live house etc. where there are many sound reflections from the floor.Only the reverberation sound and early reflection sound are output from the rear speakers 5PRL and 5PRR, and the sound from the speaker box IIL,I
IR is assumed to be in a horizontal state. Also, at this time, direct sound, early reflected sound, and reverberant sound are emitted from the center speaker 5PFC at the front center.

In this way, the elevation angles of the speaker boxes IIL and 11R are set to the optimum angle corresponding to the operation mode.
It is automatically adjusted and controlled in accordance with the operating mode of the digital signal processor 5.

The speaker boxes 11L and IIR have characters 12L and 13L corresponding to the operation mode.

12R and 13R are drawn. This character 12L
, 13L, 12R, 13R are speaker box 11L
, 11R are selectively displayed through the through holes 14L and 14R formed in the housing 24, and can be confirmed from the rear of the vehicle compartment 7.

FIG. 3 is an exploded perspective view of the speaker box IIR and the driving machine mto, which is the pointing direction changing means. Support shafts 21 and 22 arranged on a straight line protrude from both ends of the speaker box 11R, and one support shaft 21 is swingably supported by a bearing 23, and this bearing 23 is connected to the housing 24. mounted on. The other support shaft 22 is inserted through the insertion hole 26 of the holder 25, and in this state, the holder 25 is screwed and fixed to the speaker box 11R by screws 27.

The holder 25 has a first engagement protrusion 28 and a second engagement protrusion 29.
, an abutment piece 30 and a cylindrical portion 31 are provided upright. These protrusions 28, 29 and contact pieces 30 have a radius r1 centered on the axis 11 passing through the insertion hole 26 of the cylindrical portion 31.
They are placed apart by a central angle θ1 on the circle.

A bias spring 35 is wound around the outer peripheral surface of the cylindrical portion 31, one end 36 of the bias spring 35 engages with the first engagement protrusion 28, and the other end 37 engages with the first engagement protrusion 28. The bias spring 35 is engaged with the two second engagement protrusions, and the bias spring 35 generates an elastic force in the direction in which the '4 parts 36 and 37 move away from each other.

A bias spring 3 is inserted from the tip of the engagement protrusion 28, 29.
Three hooks 38 are provided to prevent the hooks 5 from falling off.

With the bias spring 35 attached to the holder 25 as described above, the support shaft 22 is inserted through the insertion hole 43 formed in the base 42 of the drive member 41, so that the drive member 41 is placed on the holder 25.

In the base portion 42, a gear 4 to which a driving force is transmitted from a driving gear 52 of a gear unit 51 is provided on a portion of the outer peripheral surface.
4 is engraved, and a first engagement piece 45 and a second engagement piece 46 are provided upright on the surface facing the holder 25.

These engaging pieces 45, 46 are arranged on a circle having a radius r2 larger than the radius r1, centered on the axis 12 passing through the insertion hole 43, and spaced apart by a center angle θ2 larger than the center angle θ1. Hooks 47 and 48 are formed at the tips of the engagement pieces 45 and 46, respectively, similar to the engagement protrusions 28 and 29.

A pressing piece 49 is provided upright on the surface of the base 42 on the gear unit 51 side. When the drive member 41 protrudes toward the back side of the support wall 53 and is angularly displaced as described later, the limit switch 5
The actuating piece 56a or 57a of 6 or 57 is pressed and displaced.

The tip of the support shaft 22 to which the drive member 41 is attached is inserted into a bearing portion 58 formed in the support member 54, and the speaker box 11R is supported swingably. Support member 5
4, on the surface facing the drive member 41, limiting protrusions 59 and 60 are erected on a circle having the radius r1 and centering on the axis 13 passing through the bearing portion 58.

The bearing 23, the holder 25, the drive member 41, and the support member 54 are made of a material such as resin, and as a result, it is possible to suppress abnormal noise generated from the bearing 23 and the bearing portion 58, especially against vibrations of the vehicle body. , the speaker box IIR can be smoothly angularly displaced.

Note that a similar configuration is provided on the speaker box 11L side, and these configurations are similar to the drive gear 52.
are interlocked and driven via a shaft 61 to which they are connected.

Therefore, the limit switches 56, 57 and the pressing piece 49 need only be provided on at least one of them, and therefore are not provided on the speaker box 11L side in order to simplify the structure.

FIG. 4 is a perspective view of the gear unit 51.

A motor 65 is attached to a base 64 that connects the support wall 53 on the side of the speaker box 11R and the support wall 63 of the speaker box 11L@.

The driving force of the motor 65 is transmitted from a driving pulley 67 attached to an output shaft 66 to a driven pulley 69 via a belt 68.

The driven pulley 69 is connected to the worm wheel 7 via the shaft 70.
1 is connected. A worm gear 72 meshes with the worm wheel 71, forming a speed reduction mechanism. Worm gear 72 is connected to gear 74 via shaft 73. A large-diameter gear 75 meshes with the gear 74, and the output of the motor 65 reduced in speed is transferred to the drive gear 52.
62, and the speaker boxes IIR and IIL are driven for angular displacement.

The torsion angle of the worm wheel 71 is formed to be relatively small, thereby setting a large reduction ratio. Furthermore, the belt 68 is formed to be extendable and retractable, and is configured to absorb loads applied from drive gears 52, 62 as described below.

In the speaker system f1 configured as described above, when the digital signal processor 5 is switched from the funky mode to the casual mode or the high-fidelity mode, the motor 65 is started and the drive member 41 moves in the direction of arrow A.
is driven for angular displacement in the direction. As a result, the first engagement piece 45
comes into contact with one end 36 of the bias spring 35, and the holder 25 is also angularly displaced in the direction of arrow A.

When the contact piece 30 of the holder 25 contacts the limiting protrusion 59,
When the angular displacement of the holder 25 stops and the drive member 41 is further angularly displaced, one end 36 of the bias spring 35 separates from the first engagement protrusion 28 of the holder 25 and engages the second engagement protrusion 29. is angularly displaced in a direction approaching . In this way, with a large elastic force generated in the bias spring 35, the pressing piece 4
9 presses the operating piece 56a of the limit switch 56, driving of the motor 65 is stopped, and the speaker 5PRL.

The 5PRR is held in an upward position as indicated by reference numeral B in FIG.

Therefore, the radiated sound from the speakers 5PRL and 5PRR reaches the listening position P after being reflected from the ceiling 15, as indicated by reference numeral 111.

Further, when the digital signal processor 5 is selected to the funky mode with the speaker boxes ILL and IIR facing upward, the motor 65 is driven and the drive member 41
is driven for angular displacement in the direction opposite to the direction of arrow A. As a result, after the engagement between the first engagement piece 45 of the drive member 41 and one end 36 of the bias spring 35 is released, the second engagement piece 46 engages with the other end 37. , holder 2
5 is driven for angular displacement in the direction opposite to the direction of arrow A.

When the contact piece 30 of the holder 25 contacts the limiting protrusion 60,
The other end 37 of the bias spring 35 is attached to the second end of the holder 25.
It is angularly displaced in a direction away from the engagement protrusion 29 and closer to the first engagement protrusion 28 . With a large elastic force generated in the bias spring 35, the pressing piece 49 comes into contact with the actuating piece 57a of the limit switch 57, the motor 65 is stopped, and the speaker boxes ILL and 11R are indicated by reference numeral C in FIG. It is held horizontally as shown.

Therefore, the radiated sound from the speakers 5PRL and 5PRR directly reaches the listening position P, as indicated by reference numeral 112.

As described above, in the sound reproduction device 2 according to the present invention, in the casual mode that reproduces a sound field such as a concert hall, the rear speakers 5PRL and 5PRR are directed upward, and the sound propagation distance to the listening position P is made longer than in the horizontal state. Therefore, the sound can be heard from the front speakers 5PFL and 5PF.
Since the sound from the R, 5 PFC reaches the listening position P later than the sound from the PFC, the sound from the front and the sound from the rear do not cancel each other out, which cannot be obtained by arithmetic processing in the digital signal processor 5. It is possible to reproduce sound with a sense of spaciousness and presence.

Further, as described above, in the speaker device 1, the bias spring 35 pushes the contact piece 30 of the holder 25 toward the limiting protrusion 5.
Since the speaker boxes ILL and 11R are always kept in pressure contact with the speaker box 9 or 60, the speaker boxes ILL and 11R do not swing even when the vehicle body vibrates, and are held securely without rattling. Therefore, noises caused by vehicle body vibrations that cause discomfort to the listener are not generated, and comfortable sound reproduction can be performed in the vehicle interior 7.

In addition, since the torsion angle of the worm wheel 71 is formed to be small, it is possible to prevent the worm wheel 71 from rotating in reverse due to the load from the drive gears 52, 62 caused by vibrations of the vehicle body, etc.
The motor 6 is connected to the worm wheel 71 via a belt 68.
By transmitting the driving force of 5, it is possible to prevent the worm wheel 71 from being jammed. However, as other embodiments of the present invention, it may be created using a delay circuit using analog signal processing, or reflection from the rear glass 16 may be used. In addition, speakers 5PRL and 5PRR are fixed,
It may be configured to change the propagation path of sound by providing a reflector in front of it, and the above-mentioned reference numeral B,
As shown by C, two sets of speakers with different pointing directions may be provided and these speakers may be switched.

Effects of the Invention As described above, according to the present invention, when sound field control is selected, the propagation distance of sound to the listening position is changed by the directional direction changing means, so that the sound signal is generated by arithmetic processing. The propagation distance of the reflected sound or reverberant sound can be set to be different from the speaker at the front of the listening position and from the speaker at the rear of the listening position, for example.
It is possible to reproduce sound with a sense of spaciousness and presence that cannot be obtained by the above-mentioned calculation processing.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the electrical configuration of a sound reproduction device 2 according to an embodiment of the present invention, FIG. 2 is a perspective view of the speaker device 1, and FIG. 3 is a speaker box 11R and a drive mechanism 10.
4 is an exploded perspective view of the gear unit 51, and FIG. 5 is a diagram showing changes in the sound propagation path due to angular displacement of the speakers 5PRL and 5PRR. 1... Speaker device, 2... Sound reproduction device, 5...
Digital signal processor, 7... Vehicle interior, 8...
Windshield, 9... Drive circuit, 10... Drive mechanism, ILL, IIR... Speaker box, 15... Ceiling, 16... Rear glass, 25... Holder, 35...
... Bias spring, 41 ... Drive member, 51 ... Gear unit, 52.62 ... Drive gear, 54 ... Support member, 65 ... Motor, 67 ... Drive pulley, 6
8... Belt, 69... Driven pulley 1/worm wheel, 2... Worm gear

Claims (2)

[Claims] (1) a sound field control means for controlling a sound field by processing an acoustic signal from an acoustic signal source; a speaker for converting the sound signal processed by the sound field control means into sound; and the sound field control means A detection means for detecting whether or not the speaker is selected; and a direction change means for changing the direction of the speaker and changing the propagation distance of the sound to the listening position in response to the detection result of the detection means. A distinctive sound reproduction device. (2) The sound reproducing device according to claim 1, wherein the pointing direction changing means is a driving means for driving a speaker box in which the speaker is housed in an angular displacement.