JP4826693B2 - Sound playback device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a speaker device arrangement method including a directivity control unit for controlling the directivity of a speaker, and a sound reproducing device using the speaker device.
[0002]
[Prior art]
As a method of controlling the change in acoustic radiation characteristics depending on the direction of the speaker (hereinafter referred to as “directivity”), conventionally, two non-directional speakers are connected in opposite phases to achieve bidirectionality, Methods such as applying a unidirectional or directional beam in a certain direction by the above speaker array have been proposed (for example, JP-A-57-068991, JP-A-05-014992 and JP-A-11-11). No. 285093, Japanese Patent Laid-Open No. 09-098495).
[0003]
These conventional methods basically achieve a desired directivity by applying a temporal delay to each speaker and utilizing spatial phase interference of sound waves depending on the speaker structure and signal processing. . In particular, when unidirectionality is realized, a direction in which the volume is reproduced at a high level (referred to as “beam direction”) and a direction in which the sound is reproduced at a low level (referred to as “zero point direction”) are generated. A sound reproduction system using the sound has been proposed. In this case, the area in the beam direction is normally used as an area where the listener is located, and the area in the zero point direction is mainly used for the purpose of lowering the volume.
[0004]
Further, in the case of reproducing monaural sound in a stereo reproduction device, if the reproduction is performed with one speaker, the perceived sound image becomes the installation position of the speaker. In addition, it is known that if stereo sound is reproduced equally between two speakers that are equidistant from a listener, it is perceived as a phantom sound image at the center of the two speakers.
[0005]
[Problems to be solved by the invention]
For this reason, if the positional relationship between the speaker and the listener is determined, the sense of distance of localization of the sound image obtained by stereo reproduction is naturally determined. Therefore, when a speaker is placed near the listener, it is difficult to obtain a sound image localization far from the actual position of the speaker. In addition, in order to obtain sound image localization far from the actual position of the speaker, signal processing such as delay processing may be performed on the acoustic signal of indirect sound or reflected sound, but the sound image localization is ambiguous. Only by doing, there is little effect that the sound image localization is felt in the distance.
[0006]
The present invention has been conceived under such circumstances, and provides an arrangement method of a speaker device in which a sound image can be sensed far from the arrangement position of the speaker, and a sound reproducing device using the speaker device. The challenge is to do.
[0007]
DISCLOSURE OF THE INVENTION
In order to solve the above problems, the present invention takes the following technical means.
[0008]
The speaker device arranging method provided by the first aspect of the present invention has a speaker mounting surface in which two speakers are arranged close to each other, and drives the two speakers to obtain a unidirectional radiation characteristic. For arranging a speaker device to which a drive signal is supplied from the directivity control unit, wherein the directivity control unit delays an input signal by a time corresponding to the distance between the two speakers and outputs the delayed input signal. A delay means; and a phase inversion means for causing the input signal and the input signal delayed by the delay means to be acoustically radiated from the two speakers in opposite phases, respectively. One of the speakers outputs an input signal delayed by the directivity control unit, and the one speaker is connected to the two speakers on the speaker mounting surface. On a straight line orthogonal to both the central axis of the over mosquitoes, is characterized by arranging so as to be located on the listener side than the other speakers.
[0009]
According to a preferred embodiment, the speaker mounting surface is arranged along the horizontal direction.
[0010]
According to another preferred embodiment, the speaker mounting surface is arranged along the vertical direction.
[0011]
According to another preferred embodiment, the speaker mounting surface is arranged such that the listener's head is located on the extended surface.
[0012]
According to another preferred embodiment, a plurality of sets of the two speakers are provided to reproduce a stereo or multi-channel sound signal. Note that this multi-channel acoustic signal is an acoustic signal including a surround signal and the like.
[0013]
According to another preferred embodiment, the directivity control unit is supplied to the other speaker with virtual localization processing means for localizing a surround signal to the side of the listener and output of the virtual localization processing means. Adding means for adding to the signal.
[0014]
The sound reproducing device provided by the second aspect of the present invention includes a speaker mounting surface in which a set of two speakers are arranged close to each other, and an input signal for a time corresponding to the distance between the set of two speakers. A delay means for outputting after delaying, and a phase inversion means for allowing the input signal and the input signal delayed by the delay means to be acoustically radiated from the pair of speakers separately in opposite phases. And a directivity control unit for driving the two sets of speakers to obtain unidirectional radiation characteristics, and either one of the two sets of speakers has the directivity The one speaker is on a straight line orthogonal to both the central axes of the two speakers on the speaker mounting surface. Than the other speaker is characterized in that it is arranged on the operation display surface side that faces the orthogonal and listeners to the speaker mounting surface.
[0015]
According to a preferred embodiment, the speaker mounting surface is arranged along the horizontal direction.
[0016]
According to another preferred embodiment, the speaker mounting surface is arranged along the vertical direction.
[0017]
According to another preferred embodiment, the speaker mounting surface is arranged such that the listener's head is located on the extended surface.
[0018]
According to another preferred embodiment, a plurality of sets of the two sets of speakers are provided to reproduce a stereo or multi-channel sound signal.
[0019]
According to another preferred embodiment, the directivity control unit is supplied to the other speaker with virtual localization processing means for localizing a surround signal to the side of the listener and output of the virtual localization processing means. Adding means for adding to the signal.
[0020]
According to another preferred embodiment, the operation display surface has operation means for a player as a listener to play a game in the game device.
[0021]
According to the present invention, the input signal is delayed by a time corresponding to the distance between the two speakers, and the delayed input signal is output from one of the two speakers. . Since this speaker device is arranged so that one speaker is positioned closer to the listener side than the other speaker, the zero point direction of the unidirectional radiation characteristic is directed to the listener side. Can feel as if the sound image is located farther than the actual speaker placement position.
[0022]
Other features and advantages of the present invention will become more apparent from the detailed description given below with reference to the accompanying drawings.
[0023]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings.
[0024]
FIG. 1 is a circuit block diagram of a main part of a game device to which a sound reproducing device having a speaker device according to an embodiment of the present invention is applied. The game device A includes a CPU 1, a ROM 2, a RAM 3, an interface circuit 4, a sound source IC 5, a directivity control unit 6, amplifiers 7Ra, 7Rb, 7La, and 7Lb, and a speaker device B. The CPU 1, the ROM 2, the RAM 3, and the interface circuit 4 are connected to each other by a bus. The speaker device B includes speakers 8Ra and 8Rb and speakers 8La and 8Lb, respectively.
[0025]
FIG. 2 is a circuit diagram of a directivity control unit partly realized by a DSP (digital signal processor). The directivity control unit 6 includes delay circuits 12R and 12L, DA converters 13Ra, 13Rb, 13La, and 13Lb, filter circuits 14Ra, 14Rb, 14La, and 14Lb, and phase inversion circuits 15R and 15L.
[0026]
The CPU 1 controls the entirety of the game apparatus A including the sound source IC 5, the directivity control unit 6, and the amplifiers 7Ra, 7Rb, 7La, and 7Lb. That is, although not shown, the game device A is provided with an operation unit, a display unit, various sensors, and the like, and the CPU 1 controls the display unit and the like according to signals from the operation unit, the sensor, and the like. .
[0027]
The ROM 2 stores a program for operating the CPU 1, fixed data, and the like.
[0028]
The RAM 3 provides a work area for the CPU 1 and stores various data.
[0029]
The interface circuit 4 controls communication between the CPU 1 and the sound source IC 5 and the directivity control unit 6.
[0030]
The sound source IC 5 stores a large number of stereo and monaural sound sources, and is controlled by the CPU 1 to output sound data.
[0031]
The directivity control unit 6 is controlled by the CPU 1 to perform directivity control processing on the acoustic data from the sound source IC 5.
[0032]
The amplifiers 7Ra, 7Rb, 7La, and 7Lb are controlled by the CPU 1 and amplify the acoustic signal from the directivity control unit 6.
[0033]
The speakers 8Ra, 8Rb, 8La, and 8Lb convert the acoustic signals from the amplifiers 7Ra, 7Rb, 7La, and 7Lb into sound. The speakers 8Ra and 8Rb are arranged close to each other and are used for right channel reproduction. The speakers 8La and 8Lb are arranged close to each other and are for left channel reproduction. These speakers 8Ra, 8Rb, 8La, and 8Lb have substantially the same acoustic characteristics.
[0034]
The delay circuits 12R and 12L delay the signal from the sound source IC5. The delay time by the delay circuits 12R and 12L is substantially equal to the sound wave propagation time at the distance between the speakers 8Ra and 8Rb and the distance between the speakers 8La and 8Lb. In this embodiment, digital delay processing is performed on the signal. However, analog delay processing may be performed by an all-pass filter with band limitation.
[0035]
The DA converters 13Ra, 13Rb, 13La, and 13Lb convert the acoustic data from the sound source IC5 and the delay circuits 12R and 12L into analog acoustic signals. That is, the DA converters 13Ra and 13La convert the acoustic data from the sound source IC5 into an analog acoustic signal, and the DA converters 13Rb and 13Lb convert the acoustic data from the delay circuits 12R and 12L into an analog acoustic signal.
[0036]
The filter circuits 14Ra, 14Rb, 14La, and 14Lb perform gain compensation and restriction on the low frequency components of the output signals from the DA converters 13Ra, 13Rb, 13La, and 13Lb. That is, since the speakers 8Ra and 8Rb are arranged close to each other and the speakers 8La and 8Lb are arranged close to each other, the low-frequency gain is relatively set to prevent the low-frequency sound from being canceled and reduced. And a low frequency component below a predetermined frequency is cut.
[0037]
The phase inversion circuits 15R and 15L invert the phases of the output signals from the filter circuits 14Rb and 14Lb. In place of the phase inversion circuits 15R and 15L, by connecting the speaker Ra or the speaker Rb and the input signal line of the speaker La or the speaker Lb with the reverse polarity, the same effect as that obtained by inverting the phase of the signal is obtained. You may comprise as follows. Further, the input signal lines of the speaker Ra or speaker Rb having opposite polarities and the speaker La or speaker Lb having opposite polarities may be connected with forward polarity.
[0038]
FIG. 3 is an external perspective view of the game apparatus A. The game apparatus A has a three-dimensional shape that is polygonal in plan view, and the front surface 16 of the game apparatus A is configured as an operation display surface facing the player. The upper surface 17 of the game apparatus A is a speaker mounting surface, and the speakers 8Ra, 8Rb, 8La, and 8Lb are arranged on the speaker mounting surface 17 so as to have an approximately inverted eight shape in plan view. Yes. Specifically, the speakers 8Ra and 8Rb are arranged close to each other at a predetermined interval in the substantially depth direction along the right edge of the upper surface 17 of the game apparatus A. The speakers 8La and 8Lb are arranged close to each other along the left side edge of the upper surface 17 of the game apparatus A with a predetermined interval in the depth direction.
[0039]
More specifically, the speaker 8Rb is disposed closer to the operation display surface 16 than the speaker 8Ra on a straight line Pr orthogonal to the central axes of the speakers 8Ra and 8Rb. Further, the speaker 8Lb is disposed closer to the operation display surface 16 than the speaker 8La on a straight line Pl orthogonal to the central axes of the speakers 8La and 8Lb. In addition, the game device A is arranged so that the player is positioned at a substantially intersection of the straight lines Pr and Pl. As will be described later, delayed and phase-inverted acoustic signals are output from the speakers 8Rb and 8Lb.
[0040]
Next, the operation will be described. In the game apparatus A, as the game of the game apparatus A is progressed by the player, the CPU 1 controls the sound source IC 5 to output acoustic data corresponding to the game situation from the sound source IC 5. This acoustic data is input to the directivity control unit 6 and subjected to directivity control.
[0041]
The acoustic data input to the right channel input terminal of the directivity control unit 6 is supplied to the DA converter 13Ra and also supplied to the delay circuit 12R.
[0042]
In the DA converter 13Ra, the input signal is converted into an analog acoustic signal and input to the filter circuit 14Ra. In the filter circuit 14Ra, the low frequency component of the input signal is relatively emphasized and the band is limited. The output of the filter circuit 14Ra is amplified by the amplifier 7Ra and output as sound from the speaker 8Ra.
[0043]
On the other hand, the signal delayed by the delay circuit 12R and supplied to the DA converter 13Rb is thereby converted into an analog acoustic signal and supplied to the filter circuit 14Rb. In the filter circuit 14Rb, the low frequency component of the input signal is relatively emphasized and band-limited, and the output is supplied to the phase inverting circuit 15R. In the phase inversion circuit 15R, the phase of the input signal is inverted, and then amplified by the amplifier 7Rb and output as sound from the speaker 8Rb.
[0044]
The acoustic data input to the left channel input terminal of the directivity control unit 6 is supplied to the DA converter 13La and also supplied to the delay circuit 12L.
[0045]
In the DA converter 13La, the input signal is converted into an analog acoustic signal and input to the filter circuit 14La. The signal whose low-frequency component is emphasized and band-limited by the filter circuit 14La is amplified by the amplifier 7La and output as sound from the speaker 8La.
[0046]
On the other hand, the signal delayed by the delay circuit 12L and supplied to the DA converter 13Lb is thereby converted into an analog acoustic signal and supplied to the filter circuit 14Lb. The output of the filter circuit 14Lb in which the low frequency component of the input signal is emphasized and band-limited is supplied to the phase inversion circuit 15L. In the phase inversion circuit 15L, the phase of the input signal is inverted, and then amplified by the amplifier 7Lb and output as sound from the speaker 8Lb.
[0047]
That is, the input signal from the acoustic IC 5 passes through the DA converters 13Ra and 13La and the filter circuits 14Ra and 14La, and the signal output from the speakers 8Ra and 8La, and the DA converters 13Rb and 13Lb and the filter circuits 14Rb and 14Lb. At the same time, delay and phase inversion are performed by the delay circuits 12R and 12L and the phase inversion circuits 15R and 15L, and the signals are divided into signals output from the speakers 8Rb and 8Lb. Note that the filter circuits 14Ra, 14Rb, 14La, and 14Lb may be provided before the delay circuits 12R and 12L.
[0048]
FIG. 4 is an explanatory diagram of unidirectional radiation characteristics in the game apparatus A. FIG. 5 is an explanatory diagram of the gain-frequency characteristics in the game apparatus A. In FIG. 4, the distance between the speakers 8Ra and 8Rb is Xm, and the acoustic signal has a single frequency of 500 Hz. In FIG. 5, the characteristics in the angle 0 [rad] direction, the angle (3/2) π [rad] direction, and the angle (1/2) π [rad] direction are shown. Of course, the speakers 8La and 8Lb have similar characteristics.
[0049]
In the speakers 8Ra and 8Rb, the distance X between the speakers 8Ra and 8Rb is limited, but in the angle (1/2) π [rad] direction, a clear volume level difference can be obtained as compared with other angle directions. Has unidirectional radiation characteristics. The sound wave cannot be made into a single beam at a high frequency. However, in the direction of the angle (1/2) π [rad], the output of the speaker 8Ra and the output of the speaker 8Rb constantly cancel each other. The level can be kept small. That is, the angle (1/2) π [rad] direction is the zero point direction of the unidirectional radiation characteristic, and the angle (3/2) π [rad] direction is the beam direction. Although the directivity shown in FIG. 4 is a directivity on a plane, it is considered that a three-dimensional beam is actually formed.
[0050]
In FIG. 5, the dip occurs in the characteristics in the angle 0 [rad] direction and the angle (3/2) π [rad] direction due to the separation distance X between the two speakers 8Ra and 8Rb. Although it is presumed that the cancellation is generated, a unidirectional beam is maintained at a frequency of about 1000 Hz or less. Since the frequency at which dip occurs shifts to a higher frequency as the distance X decreases, it is desirable to decrease the distance X between the two speakers 8Ra and 8Rb. However, the smaller the separation distance X, the larger the amount of cancellation at a lower frequency, and the greater the required compensation level. Moreover, since the diaphragm diameters of the speakers 8Ra and 8Rb are actually large, there is a limit to approaching them. Therefore, a separation distance of about 5 cm to 20 cm, preferably about 10 cm is desirable in practice.
[0051]
FIG. 6 and FIG. 7 are explanatory diagrams of acoustic effects by directivity control. In this game apparatus A, the operation display surface 16 faces the player, and the player's head is positioned on the extended surface of the speaker mounting surface 17. That is, the game apparatus A is arranged so that the speakers 8Rb and 8Lb in the zero point direction of the unidirectional radiation characteristic are closer to the player than the speakers 8Ra and 8La. If the player and the game apparatus A realize the positional relationship as described above, the zero point direction of the unidirectional radiation characteristic is directed to the player side. That is, in the player's position direction, the sound volume is reduced because the sound is canceled, but in the direction away from the player, the beam direction is used. It feels like it is located farther from the speaker placement. Further, as shown in FIG. 6, not only a sound image by stereo sound or monaural sound, but also a sound space can be developed in a predetermined range behind the game apparatus A.
[0052]
The zero point direction of the unidirectional radiation characteristic can be controlled by the delay time in the delay circuits 12R, 12L, the arrangement of the speakers 8Ra, 8Rb, 8La, 8Lb, the distance between the player and the game apparatus A, and the like. For example, in the positional relationship between the player and the game apparatus A, as shown in FIG. 8, even if the game apparatus A is provided at a position where the height of the speaker mounting surface 17 is lower than the head of the player, the above parameters are set. By setting appropriately, an appropriate zero point direction can be secured. The angle θ formed by the speaker mounting surface 17 and the player's head is preferably about 0 ° to 30 °.
[0053]
9 and 10 show the sound pressure transmission characteristics of the speakers 8Ra and 8Rb. FIG. 9 shows the case in an anechoic room, FIG. 10 shows the case in a normal listening room, and the speakers 8Ra and 8Rb and the player are about The distance is 1.5m. In each figure, D represents the unidirectional radiation characteristic in the beam direction, E represents the unidirectional radiation characteristic in the zero point direction, and F represents the omnidirectional characteristic. Here, the unidirectional radiation characteristic shown in FIG. 4 is a value obtained by calculation under conditions without reflection or the like, that is, the volume decreases in the zero point direction of the unidirectional radiation characteristic, but actually Since the diaphragm of the speaker has a certain size and there is reflection in the room, the shape of the beam and the amount of reduction in the zero point direction are different from the calculated values.
[0054]
In the case of the unidirectional radiation characteristic in the zero point direction, the level is simply reduced in an anechoic room, but in a room with reflection, a sufficient reproduction level is maintained due to indirect sound and reflected sound. . On the other hand, according to FIG. 9 and FIG. 10, in the zero point direction, the reproduction sound field has a large ratio of indirect sound and reflected sound, so that an effect of feeling a sound image in the distance can be obtained. In other words, it is known that the correlation between both ears is lowered in the case of a distant front sound source in the sound field with reflected sound, but the sound image is felt far away by creating a relatively large indirect sound field. It can be inferred that it is effective. Thus, the effect of feeling a sound image in a distant place is more conspicuous than in the case of omnidirectionality. In particular, even when a speaker is placed near a listener, a stereo sound image and a sound field space can be developed behind the speaker without feeling the presence of the speaker.
[0055]
In this way, the input signal is delayed by a time corresponding to the distance X between the two speakers 8Ra and 8Rb or the speakers 8La and 8Lb, and the delayed acoustic signal is processed to have an opposite phase to the acoustic signal from the sound source. The processed acoustic signal is configured to be output from one speaker 8Rb or 8Lb of the two speakers 8Ra and 8Rb or the speakers 8La and 8Lb. Since the game apparatus A is arranged so that the one speaker 8Rb or 8Lb is located closer to the listener side than the other speaker 8Ra or 8La, the zero point direction of the unidirectional radiation characteristic is thereby adjusted. As a result, the listener feels that the sound image is located farther from the actual speaker placement position.
[0056]
In the directivity control unit 6, the filter circuits 14Ra, 14Rb, 14La, and 14Lb are provided to relatively emphasize the low frequency components and cut the frequency components lower than the predetermined frequency, and thus the two speakers 8Ra. , 8Rb or speakers 8La, 8Lb can be satisfactorily prevented from canceling a low-frequency reproduction signal due to the proximity of each other, and thus can reproduce sound balanced in the audio band. it can.
[0057]
In the above embodiment, the two speakers 8Ra and 8Rb and the speakers 8La and 8Lb are arranged on the upper surface (speaker mounting surface) 17 of the game apparatus A, but although not shown, the operation display surface 16 of the game apparatus A is shown. Two speakers 8Ra and 8Rb and speakers 8La and 8Lb may be arranged on the side surface (excluding the speaker mounting surface 17) orthogonal to the left side. In this case, the speakers 8Rb and 8Lb are arranged so as to be located closer to the listener than the speakers 8Ra and 8La, respectively. Further, the game apparatus A may be arranged so that its lower surface is exposed, and its lower surface may be the speaker mounting surface 17. In this case, the player's head is positioned on the extended surface of the lower surface.
[0058]
In the above embodiment, the game apparatus A in which the two sets of speaker apparatuses B are integrated has been described. However, as shown in FIG. 11, the two sets of speaker apparatuses Ar and Al are provided separately, and the speaker The devices Ar and Al may be driven by another control device (not shown). In this case, the speaker devices Ar and Al are arranged so that the zero point direction of the unidirectional radiation characteristic faces the listener side, so that a sound image can be obtained farther than the speaker devices Ar and Al.
[0059]
In the above embodiment, the signals are delayed by the delay circuits 12R and 12L and then delayed by the phase inversion circuits 15R and 15L. However, after the signals are phase inverted, the signals are delayed. May be.
[0060]
FIG. 12 is a virtual circuit diagram of a directivity control unit according to another embodiment. This embodiment is different from the above-described embodiment in that a virtual localization processing circuit 29 that mainly localizes a surround signal is provided in the directivity control unit 6 ′. With this configuration, for example, a surround effect can be achieved without separately arranging surround speakers.
[0061]
Specifically, the directivity control unit 6 ′ includes the constant integration circuit 21, the addition circuits 22R and 22L, the delay circuits 23R and 23L, the filter circuits 24Ra, 24Rb, 24La, and 24Lb, the addition circuits 25R and 25L, and the phase inversion circuit 26R. , 26L, and DA converters 27Ra, 27Rb, 27La, 27Lb. Further, in this embodiment, decorrelation processing circuits 28a and 28b and a virtual localization processing circuit 29 are provided. In the directivity control unit 6 ′, circuit portions other than the DA converters 27Ra, 27Rb, 27La, and 27Lb may be configured by a DSP.
[0062]
A 5-channel surround signal can be input to the directivity control unit 6 '. That is, the 5-channel surround signals are respectively output from a sound source IC (not shown), and the left and right channel signals R and L for unidirectional control, the center signal C of the surround signal, and the 2-channel surround signal SR. , SL. The 2-channel surround signals SR and SL may be made into a 2-channel monaural surround signal by branching a 1-channel monaural signal.
[0063]
The constant integration circuit 21 multiplies the input signal by a predetermined constant. This constant is set by the CPU 1 and can be changed.
[0064]
The adder circuits 22R and 22L add the left and right channel signals R and L and the center channel signal C obtained by integrating the constants by the constant integration circuit 21.
[0065]
The addition circuits 25R and 25L add the output signals of the filter circuits 24Ra and 24La and the surround signal from the virtual localization processing circuit 29.
[0066]
The decorrelation processing circuits 28 a and 28 b perform decorrelation processing so as to have a phase difference of about 150 degrees with respect to the left and right surround signals SR and SL, and supply the processed signals to the virtual localization processing circuit 29.
[0067]
The virtual localization processing circuit 29 includes a crosstalk canceling unit that cancels the crosstalk between both ears of the player and a crossfield unit (both not shown) that gives a difference between both ears in the left and right direction of the player. A virtual localization process in which the sound image is localized in the direction of 90 degrees to the left and right with respect to the speaker is performed.
[0068]
In other configurations, each component having the same name as the above embodiment has substantially the same function.
[0069]
Explaining the operation, the left and right channel signals R and L from the sound source IC are added in the adder circuits 25R and 25L with the center channel signal C in which the constants are integrated by the constant integration circuit 21.
[0070]
The output signal of the adder circuit 22R is supplied to the adder circuit 25R via the filter circuit 24Ra. The output signal of the adder circuit 22L is supplied to the adder circuit 25L via the filter circuit 24La. In each of the addition circuits 25R and 25L, the surround signal from the virtual localization processing circuit 29 is supplied.
[0071]
That is, the left and right surround signals SR and SL from the sound source IC are supplied to the decorrelation processing circuits 28a and 28b, and after performing the decorrelation process so as to have a phase difference of about 150 degrees, the virtual localization process is performed. This is supplied to the circuit 29. In the virtual localization processing circuit 29, a virtual localization process is performed in which the sound image is localized in the direction of 90 degrees left and right with respect to the speaker in the player, and two outputs of the virtual localization processing circuit 29 are supplied to the addition circuits 25R and 25L, respectively. Is done. Thus, the surround signals SR and SL are added at an appropriate level to the channel signals R and L that are not delayed and phase-inverted.
[0072]
Note that the addition in the adder circuits 25R and 25L is a signal amplified at a low frequency in many cases in the virtual localization process, and is therefore combined with the low frequency gain compensation in the unidirectional control. This is to prevent the amplification from becoming excessive. In addition, since the virtual localization process is based on a direct sound transfer function, it is not desirable to superimpose it with unidirectional control, in order to prevent a reduction in its effect.
[0073]
The signals added in the addition circuits 25R and 25L are supplied to the DA converters 27Ra and 27La, and then amplified by the amplifiers 7Ra and 7La (see FIG. 1), and are output as sound from the speakers 8Ra and 8La.
[0074]
On the other hand, the outputs of the adder circuits 22R and 22L are delayed in the delay circuits 23R and 23L and supplied to the phase inversion circuits 26R and 26L via the filter circuits 24Rb and 24Lb. The phase is inverted by the phase inverting circuits 26R and 26L, supplied to the DA converters 27Rb and 27Lb, then amplified by the amplifiers 7Rb and 7Lb (see FIG. 1), and output as sound from the speakers 8Rb and 8Lb.
[0075]
With the sound output from the speakers 8Ra and 8La, as shown in FIG. 13, the player can localize the sound image in the 90-degree direction with respect to the game apparatus A. Therefore, the player can feel as if there are left and right surround speakers, for example. Therefore, according to this embodiment, it is not necessary to separately arrange the left and right surround speakers in addition to the normal left and right speakers, and the cost can be reduced. In addition, by performing decorrelation processing on the surround signal, it is possible to obtain a sound field feeling that is wrapped.
[0076]
Of course, the scope of the present invention is not limited to the embodiment described above. For example, in the above-described embodiment, the stereo reproduction is possible, but of course, it may be configured exclusively for monaural reproduction.
[0077]
Further, the shape of the casing of the game apparatus A is not limited to the shape in the above-described embodiment.
[0078]
Further, the sound reproducing device is not limited to being applied to the game device A in the above-described embodiment, and can be employed in any device that outputs sound, such as an in-vehicle acoustic device or a home theater device.
[Brief description of the drawings]
FIG. 1 is a circuit block diagram of a main part of a game device according to an embodiment of the present invention.
FIG. 2 is a virtual circuit diagram of a directivity control unit.
FIG. 3 is an external perspective view of the game device.
FIG. 4 is an explanatory diagram of unidirectional radiation characteristics in the game apparatus.
FIG. 5 is an explanatory diagram of gain-frequency characteristics in the game device.
FIG. 6 is an explanatory diagram of a sound effect by directivity control.
FIG. 7 is an explanatory diagram of a sound effect by directivity control.
FIG. 8 is an explanatory diagram of a sound effect by directivity control.
FIG. 9 is an explanatory diagram of gain-frequency characteristics in the game device.
FIG. 10 is an explanatory diagram of gain-frequency characteristics in the game device.
FIG. 11 is an explanatory diagram of a sound effect by directivity control according to a modification.
FIG. 12 is a virtual circuit diagram of a directivity control unit according to another embodiment.
FIG. 13 is an explanatory diagram of a sound effect by directivity control according to another embodiment.
[Explanation of symbols]
1 CPU
5 Sound source IC
6 Directivity control unit
8Ra, 8Rb, 8La, 8Lb Speaker
12R, 12L delay circuit
15R, 15L phase inversion circuit
16 Operation display screen
17 Speaker mounting surface
A game equipment
B Speaker device

Claims (7)

A speaker mounting surface in which two sets of speakers are arranged close to each other;
Delay means for delaying the input signal by a time corresponding to the separation distance between the pair of speakers and outputting the input signal, and the input signal and the input signal delayed by the delay means are in phase opposite to each other. A phase inversion unit that allows acoustic emission from each set of speakers, and a directivity control unit for driving the two sets of speakers to obtain unidirectional radiation characteristics;
One of the two sets of speakers is configured to output the input signal delayed by the directivity control unit,
The one speaker is on the operation display surface side perpendicular to the speaker mounting surface and facing the listener from the other speaker on a straight line orthogonal to both the central axes of the two speakers on the speaker mounting surface. The sound reproducing device is characterized in that the zero point direction of the unidirectional radiation characteristic is directed to the listener side . The sound reproducing device according to claim 1 , wherein the speaker mounting surface is disposed along a horizontal direction. The sound reproducing device according to claim 1 , wherein the speaker mounting surface is disposed along a vertical direction. The sound reproducing device according to any one of claims 1 to 3 , wherein the speaker mounting surface is arranged such that a listener's head is positioned on an extended surface thereof. 5. The sound reproduction device according to claim 4 , wherein a plurality of sets of the two sets of speakers are provided and reproduce a stereo or multi-channel sound signal. The directivity control unit includes virtual localization processing means for localizing a surround signal to the side of the listener, and addition means for adding the output of the virtual localization processing means to a signal supplied to the other speaker. The sound reproducing device according to claim 5 . The operation display surface, the player as a listener in the game device has operation means for performing a game, an audio reproducing device according to any one of claims 1 to 6.

Images