JPH0354992A - Speaker system - Google Patents

Abstract

PURPOSE:To obtain an efficient surround effect by the small number of speaker units by fixing plural speaker units different from each other only in compliance on both opposed baffle plates of a cabinet and fixing the units so as to operate them with mutually reversed phases. CONSTITUTION:The speaker units 1, 2 different from each other only in the compliance are fixed to the mutually opposed baffle plates 4, 5 of the cabinet 3 and electrically connected so as to be driven with mutually reversed phases. Provided that the compliance of the unit 1 is smaller than that of the unit 2. Consequently, the efficient surround effect can be applied to an audience by the small number of speaker units and the sudden drop of a sound pressure level in a low band is not generated.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a bidirectional speaker system.

2. Description of the Related Art In recent years, improvements in video technology have made it possible to show movies on a large screen even at home. Along with this, sound equipment has also come to be required to have the power and sound quality suitable for large screens.

Against this background, as shown in FIG. 4, a home video playback device 1]! The audio device combined with 11 includes two or three speaker systems 6 in front of the viewer 8, and two or more speaker systems 9 on the sides or rear.
It is often a so-called surround sound field reproduction device that uses

The front channel of this surround sound field playback device receives signals such as the audio of the software being played and background music, and the rear channel receives signals such as indirect sounds and echoes synthesized from the front channel signals using a special processing device. Handles related signals.

The subwoofer system for each channel is basically required to have performance that corresponds to the signals being handled, but if the tones of the direct sound component coming from the front and the indirect sound and reverberation components coming from the back are different, it will give the viewer a sense of discomfort. Therefore, it is desirable that the front and rear swivel systems be of the same type.

In addition, since the rear channels handle indirect sound, it is desirable to install the speaker system so that the sound from the speaker system does not directly reach the viewer and localize the sound image in order to achieve a good surround effect. For example, as shown in FIG. 4, there is a method of encircling the audience with a large number of rear subwoofer systems to disperse the sound sources and thereby achieving the above-mentioned effects. However, on the other hand, it is required to obtain the maximum effect with as few devices as possible due to the problem of installation location and costs.

In view of the above points, a rear speaker system as shown in the sectional view of FIG. 5 has been proposed. 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 to each other so that they operate in opposite phases. FIG. 6 shows the sound pressure frequency characteristics at the front of the speaker unit 1 or speaker unit 2 of the speaker system shown in the cross-sectional view of FIG. 5, and FIG.
In the loudspeaker system shown in the cross-sectional view of FIG. 5, the front side of the speaker unit 1 is 0°, and the front side of the speaker unit 2 is 180° in the frequency band above the frequency where the equivalent distance between the sound sources of the speaker unit h2 is half a wavelength. This is an example of polar coordinate directivity characteristics when the speaker unit 1. Maximum sound pressure in front of speaker unit 2, speaker unit 1,
It shows bidirectionality with the minimum sound pressure at a position equidistant from 2, that is, on the side of the cabinet.

Problems to be Solved by the Invention FIG. 8 is an example of an audio device that is combined with a home video playback device that uses the speaker system shown in the sectional view of FIG. 5 as a rear speaker system. When installing a rear speaker system as shown in Figure 7, the directional characteristics of the rear speaker system are bidirectional as shown in Figure 7, so the sound pressure is minimized near the listening position and the rear speaker system The sound does not reach the viewer directly, and a good surround effect can be given to the viewer even though a small number of them are used.

However, in the loudspeaker system shown in FIG. 5, the sound pressure of the speaker units 1 and 2 is low in the band below the frequency f0, where the equivalent distance between the sound sources of the speaker units 1 and 2 is half a wavelength, as shown in FIG. They cancel each other out, causing a sudden drop in sound pressure level, so if you want to reproduce low frequencies, you need to make the cabinet larger and increase the equivalent distance between the sound sources of speaker units 1 and 2 to reduce the frequency at which cancellation begins. This poses a serious problem in practice, as it requires lowering the level or significant level correction on the side of the amplifier that drives the speaker system.

SUMMARY OF THE INVENTION In view of the above-mentioned problems, the present invention provides a loudspeaker system that can provide a good surround effect to the viewer even though a small number of speakers are used, and that does not cause a sudden drop in sound pressure level in the low range.

Means for Solving the Problems In order to solve the above-mentioned problems, the present invention attaches speaker units that differ only in compliance to both one baffle plate and the opposing baffle plate of the cabinet, and both speaker units are arranged in opposite directions. This is based on an electrically connected configuration that operates in phase.

Effect of the Invention With the above-described configuration, the present invention can provide a good surround effect to the viewer even though a small number of speakers are used, and moreover, the sound pressure level does not suddenly drop in the low frequency range.

EXAMPLE An example of the present invention will be described below with reference to the drawings.

In FIG. 1, speaker units l1 and speaker units 2, which differ only in compliance, are each attached to one baffle plate 4 of a cabinet 3 and a baffle plate 5 facing opposite to each other, and are electrically connected to each other so as to operate in opposite phases. There is. However, the compliance of the speaker unit 1 is equal to the compliance of the speaker unit 2.

In the above configuration, in the frequency range f0 or higher where the equivalent distance between the sound sources of the speaker unit 1.2 is half a wavelength, the sound emitted from the speaker unit 1.2 has the same amplitude and opposite phase characteristics. It exhibits bidirectionality, with the maximum sound pressure at the front of the speaker unit 2 and the minimum sound pressure at a position equidistant from the speaker units 1 and 2, that is, on the side of the cabinet. On the other hand, in the low frequency range, speaker unit 1 has a smaller compliance than speaker unit 2, so the low frequency reproduction band is more limited than speaker unit 2. The front side of the speaker unit 2 when only the speaker unit 2 is driven shows the sound pressure frequency characteristic shown in FIG. 2b. Therefore, although speaker unit 1 and speaker unit 2 are in opposite phases, their amplitude levels are different, so the cancellation of sound pressure is alleviated, and the sudden drop in sound pressure level as in the speaker system shown in the cross-sectional view of Fig. 5 is alleviated. It can be prevented. FIG. 2C shows the sound pressure frequency characteristic in front of the speaker unit 2 when both the speaker unit l1 and the speaker unit 2 are driven in the speaker system with this configuration.

In the example, speaker units 1 and 2 that differ only in compliance are used, but the multi-way beaker is composed of a bass speaker unit that differs only in compliance, a mid-high sound speaker unit that has the same performance, and a dividing network. Needless to say, a configuration using a system is also effective.

FIG. 3 is a layout diagram showing an example of the audio device according to the present invention shown corresponding to the conventional example in FIG. This is an example of a case in which they are placed on both sides of the person 8. Since the rear speaker system 7 does not cause a sudden drop in sound pressure level in the low range, it is possible to obtain a better surround effect than in the conventional example.

Effects of the Invention As explained above, according to the present invention, speaker units that differ only in compliance are attached to both one baffle plate and the opposing baffle plate of the cabinet, and are electrically connected so that they operate in opposite phases to each other. As a result, it is possible to realize a subwoofer system that can provide a good surround effect to the viewer while using a small number of speakers, and that does not cause a sudden drop in sound pressure level in the low frequency range.

[Brief explanation of drawings]

Fig. 1 is a cross-sectional view of a swiveker system according to an embodiment of the present invention, Fig. 2 is a sound pressure frequency characteristic diagram of the swiveker system, and Fig. 3 is a diagram showing the sound pressure frequency characteristics of the swiveker system used as a rear swiveker system. A layout diagram showing an example of an audio device that is combined with a home video playback device. Fig. 4 shows an example of an audio device that is combined with a home video playback device that uses a conventional speaker system as a rear speaker system. Layout diagram, Figure 5 is a sectional view of a conventional bidirectional speaker system, Figure 6 is a sound pressure frequency characteristic diagram of the conventional speaker system, and Figure 7 is the polar coordinates of the conventional speaker system. The directional characteristic diagram, FIG. 8, is a layout diagram showing an example of an audio device combined with a home video playback device using the same conventional speaker system as a rear speaker system. 1, 2...Speaker unit, 3...Cabinet}, 4.5...Baffle plate, 6...Front speaker system, 7...Rear speaker system,
8...Viewer, ll...Video equipment, 12...
Input terminal! 3...Internal wiring material.

Claims (1)

[Claims] A speaker system characterized in that speaker units having different compliances are attached to both one baffle plate of a cabinet and an opposing baffle plate, respectively, and both speaker units are electrically connected so that they operate in opposite phases. .