JP2827652B2 - Sound reproduction system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an audio system for reproducing a plurality of audio signals in independent service areas.

[0002]

2. Description of the Related Art In order to realize a realistic sound field reproduction, in addition to a stereo reproduction system for reproducing signals of two channels by speaker systems disposed on the front and left and right, speakers are arranged on both sides or a rear part of a listener. A system for reproducing a surround signal from the speaker has been developed.

[0003] A conventional surround system will be described below with reference to the drawings. FIG. 6 shows the outline of the surround system. (FIG. 6)
1L, 1R are front left and right channel signals, 1SL, 1S
R is the surround signal of the rear left and right channels, 24 to 27
Is a power amplifier, 34 to 37 are speaker systems, and 5 is a listener.

The operation of the surround system configured as described above will be described. The audio signals 1L and 1R of the front left and right channels are amplified by power amplifiers 24 and 25, and a speaker system 34 arranged in front of the listener.
35 and reproduced. Further, the rear left and right surround signals 1SL and 1SR are amplified by the power amplifiers 26 and 27, applied to speaker systems 36 and 37 arranged on the side or rear of the listener 5, and reproduced. In such a surround system, since the main signals 1L and 1R of the front left and right channels are reproduced by the speaker systems 34 and 35 arranged in front of the listener 5, sound image localization is good, and the rear speaker systems 36 and 37 are provided. The surround signals 1SL and 1SR reproduced by the control unit 1 transmit the atmosphere of the reproduced sound field to the listener 5 to provide a realistic reproduction system.

[0005]

However, in order to realize a surround system with the above configuration,
There is a disadvantage that at least one surround speaker system must be arranged beside or behind the listener, and the surround speaker and the driving amplifier must be connected. Therefore, the surround system is not used much in ordinary households.

SUMMARY OF THE INVENTION In view of the above problems, the present invention provides a surround signal that must be reproduced laterally or rearward only by a speaker system that reproduces the signals of the front left and right channels while obtaining the same sense of reality as a conventional surround system. And a sound reproduction system capable of reproducing the same at the same time.

[0007]

According to the sound reproducing system of the present invention , a pair is formed in a vertical direction in which a surround signal is input.
Comprising a plurality of speakers arranged so, scan said pair
This is a system in which the surround signals are input to each of the speakers in opposite phases.

[0008]

In the sound reproduction system of the present invention, the main signal is driven in phase, so that a high sound pressure is reproduced at the center of the line array speaker system. Since the surround signal is driven upside down with respect to the center, no sound pressure is generated on the center axis of the speaker array. A listener near the center axis of the line array speaker hears only the main signal as a direct wave, and the direct wave of the surround signal does not reach the listener. Therefore, the listener converts the surround signal component to the wall, floor,
This allows the user to hear the sound reflected from the ceiling or the like and obtain a good surround sound effect without arranging the speaker system on the side or the rear.
Furthermore, control the amplitude and phase of the main signal and surround signal ,
By mixing and adding to each speaker, the directional characteristics of each signal can be controlled, and a more effective surround system can be obtained.

[0009]

An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows an audio reproducing system according to an embodiment of the present invention. In FIG. 1, reference numerals 1a and 1b denote first and second audio signals. The first audio signal 1a is amplified by the power amplifier 21 and applied to the center speaker 31 of the line array type speaker system. The second audio signal 1b is split into two, one of which is in-phase and amplified by the power amplifier 22 and added to the speaker 32, and the other signal is inverted and amplified by the power amplifier 23 to the speaker 33. Added. Therefore, the speakers 32 and 33 around the line array type speaker system are driven in opposite phases.

FIG. 2 shows directional characteristics at 500 Hz and 1 kHz when the first audio signal of the speaker system shown in FIG. 1 is reproduced. As is clear from this figure, the characteristic is reproduced in a wide range. (FIG. 3) also shows 500 Hz and 1 kHz when the second audio signal of the speaker system shown in FIG. 1 is reproduced.
The directional characteristic at z is shown. Speakers 32 and 33
Are driven in opposite phases to each other, so that they become dipole sound sources, and their directional characteristics cancel each other out on the front axis of the speaker system, so that no sound pressure is generated. Then, a zone having a high sound pressure is formed around the speaker system.

FIG. 4 shows a first example of this speaker system.
Left and right channel signals 1L, 1R as audio signals of
Shows how the sound reproduced from the speaker when the two surround signals 1SL and 1SR of the rear left and right channels are input as the second audio signal is transmitted to the listener 5. The first audio signals 1L and 1R radiated from the speaker system 3 are transmitted to the listener 5 as direct waves 6D, and the second audio signals 1SL and 1SR are
1, 72, the floor 73, and the ceiling 74 are reflected to the listener 5 as reflected sound 6R from the side and the rear. As described above, since the listener 5 does not listen to the second audio signal as a direct sound from the speaker system 3, the surround effect can be obtained only by placing the speaker system 3 in front.

FIG. 5 is a block diagram of another embodiment of the present invention, which is a system for controlling a service area in which a first audio signal is reproduced and reproducing only a place where a listener is present. In FIG. 5, the first audio signal 1a
Are demultiplexed and input to the mixing circuits 41, 42, and 43 in positive phase. The second audio signal 1b is also split and input to the mixing circuit 42 in the positive phase and to the mixing circuit 43 in the negative phase. Outputs of the mixing circuits 41, 42, 43 are amplified by power amplifiers 21, 22, 23, respectively, and applied to speakers 31, 32, 33. The directional characteristic of the second audio signal radiated from the speaker system 3 (FIG. 3)
However, the directional characteristics of the first audio signal radiated from the speaker 3 are the same as those shown in FIG.
By controlling the amplitudes and phases of 32 and 33, sharpening can be achieved. As a result, the ratio of the direct sound of the first audio signal arriving at the listener increases, and the ratio of the indirect sound arriving at the listener as reflected on the wall, floor, or ceiling can be reduced. There are advantages.

As described above, in this embodiment, three speaker units are used.
Although the system using only one speaker unit is shown, the number of speaker units is increased, and the amplitude and phase of each signal are controlled using a plurality of speaker units not only for the first audio signal but also for the second audio signal. Thereby, the directional characteristics can be optimally designed, and the surround effect for the listener can be further enhanced. Note that the directivity for the first audio signal is further sharpened by weighting the input level of the first audio signal to be input to each speaker so as to be higher for the central speaker and lower for the peripheral speakers. Therefore, the surround effect for the listener can be further enhanced. Further, the same effect can be obtained by changing the efficiency of each speaker instead of weighting the input level. Further, by arranging the radiating direction of the loudspeakers at the peripheral portion of the line array type loudspeaker system so as to be outward with respect to the radiating axis of the loudspeaker at the central portion, the second direction is achieved.
, It is possible to control the directivity characteristics of the audio signal and reduce the direct sound level to the listener, thereby realizing a better surround system.

By arranging this speaker system on both sides of a video screen such as a cathode ray tube or a screen, a surround effect can be realized without arranging a rear speaker beside or behind the listener.

[0015]

As described above, according to the present invention, the main signals are driven in the same phase in the speaker system arranged in a line, and the sub-signals are driven in the opposite phase to the speakers located symmetrically with respect to the row of speakers. As a result, the main signal is directly transmitted to the listener, and the reflected signal is transmitted only to the sub signal, so that the surround sound with a sense of realism can be provided without the need to arrange surround speakers beside or behind the listener. System can be achieved.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of an embodiment of a sound reproduction system according to the present invention.

FIG. 2 is a directional characteristic diagram when a first audio signal is reproduced in the audio reproduction system according to one embodiment of the present invention.

FIG. 3 is a directional characteristic diagram when a second audio signal is reproduced in the audio reproduction system according to one embodiment of the present invention;

FIG. 4 is a diagram illustrating a first and second reproduction modes of the sound reproduction system according to the present invention.
Diagram of the audio signal to the listener

FIG. 5 is a configuration diagram of a sound reproduction system according to another embodiment of the present invention.

FIG. 6 is a configuration diagram of a conventional sound reproduction system.

[Explanation of symbols]

 1a, 1b Audio signal 21-27 Power amplifier 3, 34, 35, 36, 37 Speaker system 31, 32, 33 Speaker unit 41, 42, 43 Mixing circuit 5 Listener 6 Direct sound from 6D speaker system 6R From speaker system Indirect sound 1L, 1R, 1SL, 1SR Audio signal 71, 72, 73, 74 Wall, floor, ceiling

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-56-110400 (JP, A) JP-A-63-261198 (JP, A) JP-A-2-62898 (JP, U) (58) Field (Int.Cl. ⁶ , DB name) H04S 5/02 H04R 3/12 H04S 1/00

Claims (7)

(57) [Claims] 1. A vertical direction in which a surround signal is input.
A plurality of speakers arranged in pairs, wherein
The sound reproduction system according to any one of claims 1 to 3, wherein the surround signals are input in opposite phases to each of the speakers . A speaker to which a main signal is input;
Are arranged so as to form a pair in the vertical direction
A plurality of speakers, and each of the paired speakers
Input the surround signals in opposite phases to each other .
Sound reproduction system according to claim Rukoto. 3. A system comprising a plurality of speakers arranged in pairs in a vertical direction , wherein at least one of the plurality of speakers is arranged.
The main signal is input to the speakers and the paired speakers
Input the surround signals out of phase with each other.
Sound reproduction system according to claim Rukoto. 4. A plurality of pairs arranged in a vertical direction.
Speaker, and for each of the plurality of speakers
A mixing circuit is provided so that the main signal is
Input to at least one of the
It will be out of phase for each of the paired speakers
Input to each of the mixing circuits,
Amplifying the output of each speaker to drive each of the speakers.
Sound reproduction system. 5. The method according to claim 1, wherein the number of speakers is three or more, and
The output sound pressure is large in the center speaker, and
It is characterized in that it is configured to be small at the peaker
The sound reproduction system according to claim 2. 6. A three-row arrangement arranged in pairs vertically.
Comprising a number or more speakers, radial direction of the speaker of the periphery
Should be external to the radiation axis of the central speaker.
In sound reproduction system arranged to be inclined to, at least one speaker of said three or more speakers
The main signal is input to each of the paired speakers.
And a surround signal input in opposite phases. 7. on either side of the image screen such as a cathode ray tube or screen, their respective arranging a plurality of speakers in the vertical direction,
Speakers for surround signals should be paired on each side
The main signals of the L and R channels are configured as main signals on each side.
Claims was partitioned speakers characterized by an input
Sound reproduction system according to any one of claims 2 to 6.