JP3899636B2 - Surround speaker system - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a surround speaker system used in an A / V (audio / visual) system or the like.
[0002]
[Prior art]
In the surround speaker system used in the A / V system, (1) as shown in FIGS. 12 and 13, the speaker 20 is a single unit and is disposed on the side of the listener (listener position) 23. Using the direct radiation method (type) in which the radiation axis 24 is directed to the listener 23 and (2) the two speakers 21 and 22 disposed on the side of the listener 23, the radiation axes 25 and 26 are There is a diffusion method (type) in which the radiation axis 25 of one speaker 21 is directed forward of the listener 23 and the radiation axis 26 of the other speaker 22 is directed backward of the listener 23 without being directed to the listener 23.
In addition, the diffusion system includes (1) a bipole system (type) in which two speakers 21 and 22 are connected in the same phase (in-phase) as shown in FIGS. As shown in FIG. 17, there is a dipole system (type) in which two speakers 21 and 22 are connected in opposite phases (reverse phase).
[0003]
By the way, since the low sound radiated (output) from the speakers 20 to 22 does not have much directivity that is a localization element of the sound image, in the direct radiation method, as shown in FIG. The (sound pressure directivity characteristic) is formed in a substantially semicircular shape.
Also, even in the bipole method, since the two speakers 21 and 22 are connected in the same phase, as shown in FIG. 14, the low frequencies emitted from these speakers 21 and 22 do not cancel each other. Thus, the low-frequency radiation pattern from both the speakers 21 and 22 is formed into a single substantially semicircular shape.
Further, in the dipole method, since the two speakers 21 and 22 are connected in opposite phases, as shown in FIG. 16, between the speakers 21 and 22, the low frequencies emitted from these speakers cancel each other, The low sound is not emitted in the listener direction, and the low sound emission pattern from each of the speakers 21 and 22 is formed in a substantially semicircular shape with a small radius.
[0004]
On the other hand, the high sound (medium / high sound) radiated from the speakers 20 to 22 has strong directivity. Therefore, in the direct radiation method, as shown in FIG. It is formed in a narrow range centered on the radiation axis 24 that is “directed”.
Also in the bipole method, as shown in FIG. 15, the high-frequency radiation pattern from the two speakers 21 and 22 is centered on the radiation axes 25 and 26 that are “directed forward or backward from the listener 23”. Since the two speakers 21 and 22 are formed in a narrow range and are connected in phase, the high-frequency sounds emitted from these speakers 21 and 22 do not cancel each other, and both speakers 21 , 22, a small radiation pattern directed toward the listener 23 is also formed.
Further, also in the dipole method, as shown in FIG. 17, as in the bipole method, the high-frequency radiation patterns from the two speakers 21 and 22 are each directed to the front or rear of the listener 23. , 26 in the narrow range. However, in the dipole method, since the two speakers 21 and 22 are connected in opposite phases, the high-frequency sounds emitted from these speakers 21 and 22 cancel each other, and between the speakers 21 and 22 A radiation pattern directed to the listener 23 is not formed.
[0005]
Each of the above-mentioned methods has advantages and disadvantages because it has the above radiation pattern for bass and treble. For example, in the direct radiation method, not only a high sound radiation pattern “strong directivity as a localization element of a sound image” is directed to the listener 23, but also a low sound radiation pattern with little directivity is centered on the speaker 20. (In other words, the direct sound component to the listener 23 in the low and high sounds (reproduced sound) radiated from both speakers 21 and 22 is very large).
Therefore, the direct emission method has a problem that the sound image is localized in the head of the listener 23 and is unnatural during monaural reproduction in which the reproduced sound is an environmental sound or the like. However, this is very effective when it is desired to localize a sound image at a speaker position or the like during surround stereo reproduction. Further, since the direct sound component to the listener 23 in the low and high sounds radiated from the speaker 20 is very large, there is no sense of lack of low or high sounds.
[0006]
On the other hand, in the dipole system, not only the high-pitched radiation pattern is not directed to the listener 23, but also the low-pitched radiation pattern is formed in a small semicircular shape centering on the speakers 21 and 22 (in other words, Therefore, in the low and high sounds radiated from both speakers 21 and 22, the direct sound component to the listener 23 is very small and the diffuse sound component (indirect sound component) not directed to the listener 23 is very large). Is difficult to localize.
Therefore, the dipole method is inappropriate when it is desired to localize the sound image at the speaker position or the like, such as during surround stereo reproduction. However, in monaural reproduction in which the reproduced sound is an environmental sound or the like, it is possible to prevent the sound image from being localized in the head of the listener 23, which is preferable.
[0007]
On the other hand, in the bipole method, a low-pitched radiation pattern is formed in a substantially semicircular shape centering on both speakers 21 and 22. Further, the high-frequency radiation pattern from the two speakers 21 and 22 is formed in a narrow range centering on the respective radiation axes 25 and 26 “directed forward or backward relative to the listener 23”, and both speakers 21. , 22 is also formed with a small treble radiation pattern directed to the listener 23 (in other words, the bass and treble radiated from both speakers 21 and 22 include not only the direct sound component to the listener 23) , Both diffuse sound components are included).
Therefore, the bipole method can be said to be an intermediate method between the direct radiation method and the dipole method, and the low sound emission pattern is formed in a substantially semicircular shape centering on both speakers 21 and 22, so that the low sound is felt insufficient. There is nothing.
[0008]
[Problems to be solved by the invention]
Recently, there has been a demand for the realization of a surround speaker system in which a bipole method or a dipole method can be selected in accordance with the type and characteristics of an acoustic source, listener preference, characteristics of a room in which audio is played, speaker layout, and the like. Yes.
[0009]
Further, when realizing the above system, there is a demand for solving the following problems in the conventional dipole method and bipole method.
That is, in the conventional dipole system, the direct sound component to the listener 23 in the low and high sounds radiated from both speakers 21 and 22 is very small, which is effective for monaural reproduction. However, even with monaural playback, there may be a case where it is better that the direct sound component to the listener 23 is large for bass with little directivity. In this case, there is a problem that the lack of bass is felt. It was.
In the bipole method, the low and high sounds radiated from both speakers 21 and 22 include not only the direct sound component to the listener 23 but also the diffuse sound component. The characteristics of can be demonstrated. However, for the high sound, only a small pattern is formed as a radiation pattern directed to the listener 23, and there is a problem that in some cases, a lack of high sound is felt.
[0010]
INDUSTRIAL APPLICABILITY The present invention can exhibit the characteristics of the first system and the bipole system that can exhibit the characteristics of the dipole system according to the type and characteristics of the acoustic source, the listener's preference, the characteristics of the room in which the audio is played, the speaker layout, and the like. Either the second method can be selected, and when the first method is selected, the direct sound component to the listener in the radiated bass is selected, and when the second method is selected, the direct sound to the listener in the radiated high tone is selected. An object of the present invention is to provide a surround speaker system in which the components can be increased or decreased.
[0011]
[Means for Solving the Problems]
In order to achieve the above object, the present invention is characterized in that the first to third speakers attached to one cabinet are disposed on the side of the listener position, and the radiation axis of the first speaker is the listener. The radiation axis of the second speaker is directed to the rear of the listener position, the radiation axis of the third speaker is directed to the listener position , and the third speaker is connected to the first input terminal for sound signal input. A first input terminal, an inductor, and a capacitor are connected, and a second input terminal of the first speaker is connected to the second input terminal for acoustic signal input . Either inductor and a capacitor, and a first selection switch for connecting the first input terminal of the first speaker and the second input terminal of the third speaker, B. C. a second selection switch for selectively connecting the first and second input terminals of the second speaker to a midpoint of connection between the first input terminal of the first speaker and the first selection switch; With respect to the second input terminal for sound signal input, and a third selection switch for selectively connecting the first and second input terminal of the second speaker, D. One end is connected to the first input terminal for sound signal input, the other end is connected to the first input terminal of the first speaker, and the volume of high sound output from the third speaker when the inductor is selected by the first selection switch And a volume adjusting means for adjusting the volume of the bass output from the third speaker when the capacitor is selected by the first selection switch, and the first selection switch to the third selection switch work together to select the first selection. When the inductor is selected by the switch, the first input terminal of the second speaker is selected by the second selection switch, the second input terminal of the second speaker is selected by the third selection switch, and the first selection switch When the capacitor is selected by the second selection terminal, the second input terminal of the second speaker is selected by the second selection switch, and the second speaker is selected by the third selection switch. In that the first input terminal is selected.
The volume adjusting means adjusts the volume of high sounds radiated from the first and second speakers when the inductor is selected by the first selection switch, and at the time of selecting the capacitor by the first selection switch. also adjust the volume of the bass emitted from the speaker.
Further, the volume adjusting means of the volume adjustment means of the first and second speaker third speaker, as at the time of one volume increase and the other volume decreases, Ru mower be interlocked.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an example of an embodiment of the present invention will be described with reference to the drawings of FIGS. 1 to 11. FIG. 1 shows a surround speaker system. In FIG. 1, 1 is a + side input terminal (first input terminal) for acoustic signal input, and 2 is a-side input terminal (second input terminal) for acoustic signal input. One end of each of the inductor L and the capacitor C is connected to the + side input terminal.
[0013]
SP1 to SP3 are first to third speakers, which are arranged on the side of the listener (listener position) 4 and attached to one cabinet as shown in FIGS. 4, 5, 8 and 9. Yes. Further, the radiation axis 5 of the first speaker SP1 than the listener 4 directed forward (side), the radiation axis 6 of the second speaker SP2 is directed backward (side) than the listener 4, the third speaker SP3 The radial axis 7 is directed toward the listener 4. Each of the speakers SP1 to SP3 has a + side input terminal (first input terminal) and a − side input terminal (second input terminal), and the − side input terminal of the first speaker SP1 is used for acoustic signal input. The positive input terminal of the third speaker SP3 is connected to the positive input terminal 1 for acoustic signal input.
[0014]
SW <b> 1 to SW <b> 3 are first to third selection switches, and by these operations, one of a first method capable of exhibiting a dipole characteristic and a second method capable of exhibiting a bipole characteristic are selected.
[0015]
The first selection switch SW1, the + side input terminal of the first speaker SP1 and the third speaker SP3 - to negative input terminals, one of the other end of the inductor L and the capacitor C is intended to connect an inductor L Terminals B1 and D1 connected to the other ends of the capacitor C, and a switch portion F1 connected to the positive side input terminal and selectively connected to the terminals B1 and D1.
The second selection switch SW2 selectively connects the + side input terminal of the second speaker SP2 to the midpoint of connection between the + side input terminal of the first speaker SP1 and the first selection switch SW1, Terminals B2 and D2 connected to the + side and − side input terminals of the second speaker SP2 and a switch part F2 connected to the connection midpoint and selectively connected to the terminals B2 and D2.
The third selection switch SW3 selectively connects the negative side input terminal of the second speaker SP2 to the negative side input terminal 2 for acoustic signal input, and the negative side input terminal of the second speaker SP2. A switch unit F3 connected to the negative input terminal 2 for acoustic signal input and selectively connected to the terminals B3 and D3.
[0016]
As shown in FIG. 2, the operation units 9 of the first to third selection switches SW1 to SW3 are combined into a single snap switch type, so that the first to third selection switches SW1 to SW3 are The first mode selection posture in which the switch portions F1 to F3 are connected to the terminals B1 to B3 and the second mode selection posture in which the switch portions F1 to F3 are connected to the terminals D1 to D3. It is possible to switch to any posture. In FIG. 2, for the sake of clarity, the first method is displayed as a bipole, and the second method is displayed as a dipole.
[0017]
Then, when the inductor L is selected by the first selection switch SW1, the volume of treble radiated (output) from the first to third speakers SP1 to SP3 is adjusted, and when the capacitor C is selected by the first selection switch SW1. A variable resistor VR is used as a volume adjustment unit that adjusts the volume of the bass emitted (output) from the first to third speakers SP1 to SP3. One end of the variable resistor VR is connected to the positive input terminal 1 for acoustic signal input, and the other end is connected to the positive input terminal of the first speaker SP1 and the negative input terminal of the third speaker SP3. ing. As shown in FIG. 3, the knob 10 of the variable resistor VR is a rotary type. Further, in FIG. 3, “the operation position of the knob 10” in which the resistance value of the variable resistor VR is zero is displayed as “no correction” (that is, no volume adjustment), and the resistance value of the variable resistor VR is the maximum. A certain “operation position of the knob 10” is displayed as “maximum correction” (that is, when adjusting the maximum volume).
[0018]
In the above configuration example, audio playback is performed in the first method that can exhibit the characteristics of the bipole method according to the type and characteristics of the sound source, the preference of the listener 4, the characteristics of the room in which the audio is played, the layout of the speakers, and the like. As shown in FIG. 1, the switch units 1 to F3 are connected to the terminals B1 to B3 with the first to third selection switches SW1 to SW3 as the first system selection posture. As a result, the inductor L is connected to the positive input terminal of the first speaker SP1, and the first and second speakers SP1 and SP2 are connected in parallel with each other, and the first and second speakers SP1 and SP2 are connected in parallel. In contrast, the third speaker SP3 is connected in phase.
[0019]
In this case, the inductor L has a large impedance for the high frequency signal, but has a small impedance for the low frequency signal, so that the low impedance between the input terminals of the first and second speakers SP1 and SP2 is low. The band signal voltage becomes large, and the low band signal voltage between both input terminals of the third speaker SP3 becomes small. Accordingly, the volume (sound pressure) of the bass radiated from the first and second speakers SP1, SP2 is (very) large, and the volume of the bass radiated from the third speaker SP3 is (very) small.
At this time, there is not much directivity with respect to the bass, and the first and second speakers SP1 and SP2 are connected in the same phase, so that the bass emitted from these speakers SP1 and SP2 cancel each other out. Accordingly, as shown in FIG. 4, the low-frequency radiation pattern from the first and second speakers SP1, SP2 (and the third speaker SP3) is formed in a substantially semicircular shape.
[0020]
On the other hand, the high-frequency signal voltage between the input terminals 1 and 2 for sound signal input is adjusted for the first and second speakers SP1 and SP2 and the third speaker SP3 by adjusting the variable resistor VR. Can be divided as desired. Therefore, the high sound volume (sound pressure) of the first and second speakers SP1, SP2 and the high sound volume of the third speaker SP3 can be adjusted as desired, and at the time of this adjustment, the first and second speakers SP1, SP2 The volume of the emitted bass and the volume of the bass emitted from the third speaker SP3 do not change.
In addition, in the above case, the high sound has high directivity, and the first to third speakers SP1 to SP3 are connected in phase, so that the high sounds radiated from these do not cancel each other out. As shown, the high-frequency radiation pattern from each of the speakers SP1 to SP3 is formed in a relatively narrow range around the radiation axes 5 to 7 of each speaker.
[0021]
As described above, when audio reproduction is performed while taking advantage of the characteristics of the bipole method, the high sound volume of the first and second speakers SP1, SP2 and the high sound volume of the third speaker SP3 can be adjusted as desired. For example, the volume of the high sound from the first and second speakers SP1 and SP2 is reduced so that “the radial axes 5 and 6 are directed forward or backward relative to the listener 4”, and “the radial axis 7 is directed toward the listener 4”. By increasing the volume of the treble sound from the three speakers SP3, the direct sound component can be increased while reducing the diffuse sound component in the treble radiated from the speakers SP1 to SP3, and the lack of treble can be eliminated as necessary. .
[0022]
This will be further described with reference to FIG. The circuit shown in FIG. 6 is a equivalent circuit shown in FIG. 1, in FIG. 6, E _s is the input signal voltage between the input terminals for the acoustic signal input, R _L1 is the first and second speaker , V ₁ is the voltage between both input terminals of the first and second speakers, R _L2 is the resistance value of the third speaker, V ₂ is the voltage between both input terminals of the third speaker, and R is variable The resistance value of the resistor, L is the inductance value of the inductor.
[0023]
Then, when the angular frequency of the input signal is ω, the value of the ratio of V ₁ and E _s is H ₁ , and the value of the ratio of V ₂ and E _s is H ₂ , H ₁ and H ₂ are obtained as follows. .
H ₁ = V ₁ / E _s = {1+ (jω / ω ₂ )} / {1+ (jω / ω ₁ )}
H ₂ = V ₂ / E _s = (jω / ω ₃ ) / {1+ (jω / ω ₁ )}
However, ω ₁ = RR _L1 R _L2 / L {R (R _L1 + R _L2 ) + R _L1 R _L2 }
ω ₂ = RR _L2 / {L (R + R _L2 )}
ω ₃ = R _L1 / L
[0024]
Figure 7 is a graph showing the relationship between the "H ₁ and H ₂ of the logarithm of the absolute value" and "logarithm of omega", log | H ₁ | For, when _{ω ≦ ω 1, log | H} 1 | When ω ₁ <ω <ω ₂ , log | H ₁ | decreases with a slope of −6 dB / oct, and when ω ₂ ≦ ω, log | H ₁ | = ω ₁ / ω _2. . For log | H ₂ |, log | H ₂ | increases with a slope of 6 dB / oct when ω ≦ ω ₁ , and log | H ₂ | = ω ₁ / ω when ω ₁ ≦ ω. ₃ When R = 0, log | H ₁ | = 1 and log | H ₂ | = 0.
[0025]
Further, when audio reproduction is performed in the second method that can exhibit the characteristics of the dipole method, the first to third selection switches SW1 to SW3 are set as the second method selection posture, contrary to FIG. The parts 1 to F3 are connected to the terminals D1 to D3. Thereby, the capacitor C is connected to the + side input terminal of the first speaker SP1, and the first and second speakers SP1, SP2 are connected in reverse phase and in parallel. The third speaker SP3 is connected in phase with the first speaker SP1, but is connected in opposite phase with respect to the second speaker SP2.
[0026]
In this case, the capacitor C has a large impedance for the low-frequency signal, but has a small impedance for the high-frequency signal. Therefore, the capacitor C has a high impedance between the input terminals of the first and second speakers SP1 and SP2. The band signal voltage becomes large, and the high band signal voltage between both input terminals of the third speaker SP3 becomes small. Therefore, the volume of the treble radiated from the first and second speakers SP1 and SP2 is (extremely) large, and the volume of the treble radiated from the third speaker SP3 is (extremely) small.
At this time, since the directivity of the high sound is strong, as shown in FIG. 8, the high sound radiation pattern from the first and second speakers SP1 and SP2 is the radiation axis 5 of the first and second speakers SP1 and SP2. , 6 in a narrow range. Since the volume of the high sound emitted from the third speaker SP3 is low, the high-frequency radiation pattern from the third speaker SP3 is omitted in FIG.
[0027]
On the other hand, the low-frequency signal voltage between the input terminals 1 and 2 for sound signal input is adjusted for the first and second speakers SP1 and SP2 and the third speaker SP3 by adjusting the variable resistor VR. Can be divided as desired. Accordingly, the volume of the bass emitted from the first and second speakers SP1 and SP2 and the volume of the bass emitted from the third speaker SP3 can be adjusted as desired, and at the time of this adjustment, the first and second speakers SP1 and SP2 are adjusted. The volume of the high tone radiated from SP2 and the volume of the high tone radiated from the third speaker SP3 do not change.
Further, in the above case, the bass is not very directional, and the first and third speakers SP1 and SP3 are connected in the same phase, and the bass radiated from these speakers SP1 and SP3 As shown in FIG. 9, the low-frequency radiation patterns from both speakers SP1 and SP3 form a substantially semicircular shape. On the other hand, since the second speaker SP2 and the third speaker SP3 are connected in opposite phases, the bass emitted from these speakers SP2 and SP3 cancel each other, and the second speaker SP2 The bass radiation pattern is formed in a relatively narrow range around the radiation axis 6.
[0028]
As described above, when audio reproduction is performed while taking advantage of the characteristics of the dipole method, the low sound volume of the first and second speakers SP1, SP2 and the low sound volume of the third speaker SP3 can be adjusted as desired. For example, the volume of the low sound from the first and second speakers SP1 and SP2 is reduced so that “the radial axes 5 and 6 are directed forward or backward relative to the listener 4”, and “the radial axis 7 is directed toward the listener 4”. By increasing the volume of the low sound from the three speakers SP3, the direct sound component can be increased while reducing the diffuse sound component in the low sound radiated from the speakers SP1 to SP3, and the lack of low sound can be eliminated as necessary. .
[0029]
This will be further described with reference to FIG. The circuit shown in FIG. 10 is the equivalent circuit of FIG. 1 when the first to third selection switches are in the second system selection posture, and the symbols in FIGS. 10 and 6 are substantially the same. C in FIG. 10 is a capacitance value of the capacitor. Again, the angular frequency of the input signal omega, the value of the ratio of V ₁ and E _s the value of the ratio of H _1, V ₂ and E _s as H _2, when obtaining the H _1, H _2, the following formula It becomes.
H ₁ = V ₁ / E _s = ω ₆ {1+ (jω / ω ₅ )} / {1+ (jω / ω ₄ )}
H ₂ = V ₂ / E _s = ω ₇ / {1+ (jω / ω ₄ )}
However, ω ₄ = {R (R _L1 + R _L2 ) + R _L1 R _L2 } / CRR _L1 R _L2
ω ₅ = (R + R _L2 ) / CRR _L2
ω ₆ = {R _L1 (R + R _L2 )} / {R (R _L1 + R _L2 ) + R _L1 R _L2 }
ω ₇ = RR _L2 / {R (R _L1 + R _L2 ) + R _L1 R _L2 }
[0030]
FIG. 11 is a graph showing the relationship between the logarithm of the absolute values of H ₁ and H ₂ and the logarithm of ω. For log | H ₁ |, log | H ₁ | = ω when ω ≦ ω _{5. 6} and log | H ₁ | increases with a slope of 6 dB / oct when ω ₅ <ω <ω ₄ , and log | H ₁ | = 1 when ω ₄ ≦ ω. For log | H ₂ |, log | H ₂ | = ω ₇ when ω ≦ ω ₄ , and log | H ₂ | has a slope of −6 dB / oct when ω ₄ <ω. Decrease. When R = 0, log | H ₁ | = 1 and log | H ₂ | = 0.
[0031]
In the above embodiment, the first input terminal is the + side input terminal and the second input terminal is the − side input terminal, but this may be reversed. In the present invention, the signal line may be an unbalanced type, but the signal line may be a balanced type and each input terminal may be a hot side terminal or a cold side terminal.
[0032]
【The invention's effect】
As described above in detail, according to the present invention, the first method that can exhibit the characteristics of the dipole method according to the type and characteristics of the acoustic source, the listener's preference, the characteristics of the room in which the audio is played, the layout of the speakers, and the like. And, any one of the second methods that can exhibit the characteristics of the bipole method can be selected. In addition, when the first method is selected, the direct sound component in the radiated bass can be increased / decreased, and if necessary, the shortage of the bass can be eliminated, and when the second method is selected, the direct sound component in the radiated treble is increased / decreased. If necessary, it can eliminate the lack of treble.
[0033]
Further , even when the direct sound component in the radiated bass is increased or decreased when the first method is selected, it is possible to prevent a change in the volume of the high sound radiated from each speaker and to be radiated when the second method is selected. Even when the direct sound component in treble is increased or decreased, it is possible to prevent a change in volume of the bass emitted from each speaker.
[Brief description of the drawings]
FIG. 1 is a circuit diagram showing an example of an embodiment of the present invention.
FIG. 2 is a perspective view illustrating an operation unit of the selection switch of FIG. 1;
FIG. 3 is a front view showing a knob of the variable resistor of FIG. 1;
FIG. 4 is an explanatory diagram showing an example of a bass emission pattern according to an example of an embodiment of the present invention;
FIG. 5 is an explanatory diagram showing an example of a treble radiation pattern according to an example of an embodiment of the present invention.
6 is an equivalent circuit of FIG.
FIG. 7 is a graph for explaining the relationship between the angular frequency and the volume of reproduced sound from each speaker according to an example of the embodiment of the present invention.
FIG. 8 is an explanatory diagram showing an example of a treble radiation pattern according to an example of an embodiment of the present invention.
FIG. 9 is an explanatory diagram illustrating an example of a bass radiation pattern according to an example of an embodiment of the present invention;
10 is an equivalent circuit of FIG. 1 when the selection switch is switched.
FIG. 11 is a graph for explaining the relationship between the angular frequency and the volume of reproduced sound from each speaker according to an example of the embodiment of the present invention.
FIG. 12 is an explanatory diagram showing an example of a conventional bass radiation pattern.
FIG. 13 is an explanatory diagram showing an example of a high-pitched sound radiation pattern according to a conventional example.
FIG. 14 is an explanatory diagram showing an example of a conventional bass radiation pattern.
FIG. 15 is an explanatory diagram showing an example of a high-pitched radiation pattern according to an example of the prior art.
FIG. 16 is an explanatory diagram showing an example of a conventional bass radiation pattern.
FIG. 17 is an explanatory diagram showing an example of a high-pitched sound radiation pattern according to a conventional example.
[Explanation of symbols]
1, 2 For sound signal input + side and-side input terminals (first and second input terminals)
5-7 Radial axis C Capacitor L Inductors SP1-SP3 First-third speakers SW1-SW3 First-third selection switch VR Variable resistor

Claims (3)

The first to third speakers attached to one cabinet are arranged on the side of the listener position,
The radiation axis of the first speaker is directed forward from the listener position,
The radiation axis of the second speaker is directed behind the listener position,
The radiation axis of the third speaker is directed to the listener position,
The first input terminal of the third speaker, the inductor and the capacitor are connected to the first input terminal for acoustic signal input,
The second input terminal of the first speaker is connected to the second input terminal for sound signal input,
A. Either inductor and a capacitor, and a first selection switch for connecting the first input terminal of the first speaker and the second input terminal of the third speaker,
B. A second selection switch for selectively connecting the first and second input terminals of the second speaker to the midpoint of connection between the first input terminal of the first speaker and the first selection switch;
C. A third selection switch for selectively connecting the first and second input terminals of the second speaker to the second input terminal for sound signal input;
D. One end connected to a first input terminal for sound signals input, the other end is connected to the second input terminals of the third speaker, when the inductor of selection by the first selection switch, treble output from the third speaker Volume adjustment means is provided for adjusting the volume of the bass output from the third speaker when the capacitor is selected by the first selection switch, as well as adjusting the volume.
The first to third selection switches are linked,
When the inductor is selected by the first selection switch, the second input switch selects the first input terminal of the second speaker, and the third selection switch selects the second input terminal of the second speaker.
When the capacitor is selected by the first selection switch, the second input terminal of the second speaker is selected by the second selection switch, and the first input terminal of the second speaker is selected by the third selection switch. Surround speaker system featuring. The volume adjusting means adjusts the volume of high sound radiated from the first and second speakers when the inductor is selected by the first selection switch, and from the first and second speakers when the capacitor is selected by the first selection switch. surround speaker system according to claim 1, wherein adjusting the volume of the bass emitted.   The surround speaker system according to claim 2, wherein the volume adjusting means of the first and second speakers and the volume adjusting means of the third speaker are interlocked so that when one volume increases, the other volume decreases.

Images