JPH06105998B2 - Speaker system - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a speaker system having bidirectionality.

2. Description of the Related Art In recent years, improvements in video image technology have made it possible to show movies on a large screen at home. Accompanied by this, audio equipment has also been required to have the power and sound quality suitable for a large screen. From such a background, as shown in FIG. 4, the audio device combined with the home video reproducing device 14 has three or three speaker systems 9 in front of the viewer 11 and two or three speaker systems 9 in the side or in the rear. It is often a so-called surround sound field reproducing device using the above speaker system 12.

The front channel of this surround sound field reproducing device is a signal such as software voice or background music to be reproduced, and the rear channel is a signal related to indirect sound or reverberation which is obtained by synthesizing the signal of the front channel using a special processing device. We are dealing. For the speaker system of each channel, the performance corresponding to the signal to be handled is basically required, but if the timbre of the direct sound component coming from the front and the timbre of the indirect sound and the reverberation component coming from the back are different, it gives the viewer a feeling of strangeness It is desirable that the front and rear speaker systems have the same type as much as possible.

Since the rear channel handles indirect sound, it is desirable to install a speaker system so that the sound from the speaker system does not reach the viewer directly and the sound image is not localized in order to improve a good surround effect. For example, as shown in FIG. 4, there is a method in which a large number of rear speaker systems are used to surround a viewer so as to disperse sound sources and enhance the above effect. However, on the other hand, it is required to use a small number of speaker systems as much as possible in order to obtain an effect from the viewpoint of installation location and cost.

From the above points, a speaker system as shown in the sectional view of FIG. 5 has been proposed as a rear speaker system. In FIG. 5, 1 and 2 are speaker units having the same performance, 3 is a cabinet, and the speaker units 1 and 2 are electrically connected so as to operate in opposite phases. FIG. 6 is a sound pressure frequency characteristic in front of the speaker unit 1 or the speaker unit 2 of the speaker system shown in the sectional view of FIG. 5, and FIG.
In the speaker system shown in the sectional view of the figure, the front side of the speaker unit 1 in the band equal to or higher than the frequency where the equivalent distance between the sound sources of the speaker units 1 and 2 becomes a half wavelength is 0.
゜, an example of polar coordinate directional characteristics when the front side of the speaker unit 2 is set to 180 °, and the sound pressure is maximum at the front of the speaker units 1 and 2 and at a position equidistant from the speaker units 1 and 2, that is, the cabinet side. It shows bidirectionality that minimizes sound pressure.

Problems to be Solved by the Invention FIG. 8 is an example of an audio device combined with a home video reproducing device using the speaker system shown in the sectional view of FIG. 5 as a rear speaker system. When the speaker systems 9 and 13 are installed in the rear speaker system 13, since the directional characteristics of the rear speaker system 13 are bidirectional as shown in FIG. Sound does not reach viewer 11 directly,
A good surround effect can be given to the viewer while using a small number.

However, in the speaker system shown in FIG. 5, as shown in FIG. 6, the sound pressures of the speaker units 1 and 2 are equal to or less than the frequency f _{c at} which the equivalent distance between the sound sources of the speaker units 1 and 2 becomes a half wavelength. Since they cancel each other out and cause a sudden drop in sound pressure level, if you want to reproduce in the low frequency range, make the cabinet large and make the speaker unit 1.
The equivalent distance between the two sound sources is increased to lower the frequency at which cancellation occurs, or a large level correction is required on the amplifier side that drives the speaker system, which causes a serious problem in practical use.

In view of the above problems, the present invention provides a speaker system that can provide a good surround effect to a viewer while using a small number of speakers and that does not cause a sudden decrease in sound pressure level in a low frequency range.

Means for Solving the Problems In order to solve the above problems, the present invention is to install speaker units having the same performance on both baffle plates facing each other and one baffle plate in the cabinet, and the inside volumes of the cabinet are different from each other. And the speaker units are electrically connected so that both speaker units operate in opposite phases.

Effects The present invention can give a good surround effect to a viewer while using a small number of devices with the above-described configuration, and does not cause a sudden drop in sound pressure level in the low frequency range.

Embodiment An embodiment of the present invention will be described below with reference to the drawings.

In FIG. 1, a speaker unit 1 having the same performance,
2 are attached to one baffle plate 5 facing the one baffle plate 4 of the cabinet 3, respectively. The interior of the cabinet 3 is divided by the partition plate 6 into the cavity 7 inside.
And 8 are partitioned to have different volumes.
The speaker units 1 and 2 are electrically connected so that they operate in opposite phases.

In the above configuration, in the band where the equivalent distance between the sound sources of the speaker units 1 and 2 is equal to or more than the half wavelength, the sound emitted from the speaker units 1 and 2 has the same amplitude and opposite phase characteristics, so that the speaker units 1 and 2 It shows a bidirectional pattern in which the sound pressure is maximum in front of the speaker, and the sound pressure is minimum at positions equidistant from the speaker units 1 and 2, that is, at the sides of the cabinet. On the other hand, in the low frequency range, since the cavities 7 and 8 have different internal volumes, the speaker unit 1 is in front of the speaker unit 1 as shown in FIG. 2a, and the speaker unit 2 is in front of the speaker unit 1 as shown in FIG. 2b.
It shows different low-range reproduction limits like the sound pressure frequency characteristics. Therefore, since the speaker units 1 and 2 have opposite phases, but the amplitude levels are different, the cancellation of the sound pressure is alleviated,
It is possible to prevent a sudden decrease in sound pressure level as in the speaker system shown in the sectional view of FIG. FIG. 2c is a sound pressure frequency characteristic in front of the speaker unit 1 when both speaker units 1 and 2 are driven in the speaker system according to the present configuration.

In the embodiment, the speaker units 1 having the same performance are
Although 2 is used, it goes without saying that a configuration using a multi-way speaker system composed of a speaker unit having the same performance and a dividing network is also effective.

FIG. 3 is a layout diagram showing an example of an audio device according to the present invention shown in correspondence with the conventional example shown in FIG. This is an example of arrangement on both sides. The rear speaker system 10 does not cause a sudden decrease in sound pressure level in the low frequency range, and thus can obtain a better surround effect than the conventional one.

As described above, according to the present invention, speaker units having the same performance are attached to both one baffle plate and a baffle plate facing each other in the cabinet, and the interior of the cabinet is partitioned to have different internal volumes, Moreover, since both speaker units are electrically connected so that they operate in opposite phases, a good surround effect can be provided to the viewer while using a small number of speakers, and the sound pressure level drops sharply in the low range. A speaker system that does not cause noise can be realized.

[Brief description of drawings]

FIG. 1 is a sectional view of a speaker system in one embodiment of the present invention, FIG. 2 is a sound pressure frequency characteristic diagram of the speaker system in the embodiment, and FIG. 3 is a speaker system shown in the sectional view of FIG. FIG. 4 is a layout view showing an example of an audio device combined with a home video reproduction device used as a rear speaker system, and FIG. 4 is an audio device combined with a home video reproduction device using a conventional speaker system as a rear speaker system. Fig. 5 is a cross-sectional view of a conventional speaker system having both directivity, Fig. 6 is a sound pressure frequency characteristic diagram of the speaker system, and Fig. 7 is a polar coordinate directional characteristic diagram of the speaker system. FIG. 8 is a layout diagram showing an example of an audio device combined with a home video reproducing device using the same speaker system as a rear speaker system. . 1,2 …… Speaker unit, 3 …… Cabinet, 4,5…
… Baffle board, 6 …… intermediate partition board, 7,8 …… cavity,
9 ... Front speaker system, 10 ... Rear speaker system, 11 ... Viewer, 14 ... Video equipment, 15 ... Input terminals, 16a, 16b ... Internal wiring materials.

Claims (1)

[Claims] 1. A speaker unit having the same performance is attached to both one baffle plate and a baffle plate facing each other in a cabinet, and the inside of the cabinet is partitioned so as to have different internal volumes, and both speaker units have opposite phases. A speaker system characterized by being electrically connected so as to operate in.