JPH02220599A - Speaker system for reproducing low-pitched sound - Google Patents

Abstract

PURPOSE:To attenuated undesired high frequency range component and to improve the low frequency range reproducing efficiency by adopting the constitution such that an opening of an acoustic tube at a rear side of a speaker unit is linked to an air chamber provided to a front face of the unit. CONSTITUTION:Since a speaker system B of a base-reflex type comprising an air chamber 5 and a port 6 is formed to a front face 2b of a speaker unit 2, a low frequency range near the resonance frequency of the port 6 is nearly in opposite phase and led to an outer part 7 of a speaker enclosure 1. On the other hand, the sound discharged to a rear side 2a of the unit 2 is led to the opening 8 of the acoustic tube 3 and the low frequency range near the frequency whose half wavelength is nearly equal to the length of the tube 3 is made again in opposite phase. Thus, the sound at the front face 2b of the unit 2 and the sound at the rear side 2a are added and the low frequency range is reproduced efficiently and the high frequency range component is attenuated efficiently by the filter effect of the air chamber 5. Thus, undesired high frequency range component is attenuated and the reproducing efficiency of the low frequency range is improved.

Description

[Detailed description of the invention] (b) Industrial application field The present invention relates to a speaker system for bass reproduction.

(b) Prior art/Problems to be solved by the invention Hitherto, as a speaker system for bass reproduction, a speaker system for bass reproduction, such as the one described in Japanese Patent Application Laid-open No. 120586/1986, has been known. It is being

FIG. 4 is a sectional view showing the above-described speaker system.

However, the above-mentioned conventional system has a drawback in that unnecessary high-frequency components leak through the acoustic tube 10 to the front part 12 of the speaker system from the opening I+.

The present invention has been made in view of the above points, and an object thereof is to provide a speaker system for bass reproduction that can further attenuate unnecessary high-frequency components.

(C) Means for Solving the Problem This invention consists of an acoustic tube formed continuously from the back of the speaker unit, a cavity provided in the front of the speaker unit, and a bass reflex port provided in this cavity. In this bass sound reproduction speaker system, the opening of the acoustic tube is connected to a vacant room.

Further, the resonant frequency of the bass reflex port and the frequency at which a half wavelength is placed on the acoustic tube are configured to be approximately the same.

(d) Effects According to the present invention, bass sound is made up of an acoustic tube formed continuously from the back surface of the speaker unit, a cavity provided in the front of the speaker unit, and a bass reflex port provided in this cavity. Since the reproduction speaker is configured such that the opening of the acoustic tube is connected to the empty chamber, high frequency components reproduced by the speaker unit are attenuated by the filter effect of the empty chamber.

In addition, since the resonant frequency of the bass reflex port and the frequency at which a half wavelength is placed on the acoustic tube are approximately the same, the sound is emitted to the front side of the speaker unit and the sound emitted to the back side of the speaker unit. The in-phase sound is in phase with the out-of-phase sound and is added to the part consisting of the empty room and the port.

Since the empty chamber and the port form a bass reflex speaker system, the low frequency range is efficiently radiated to the outside.

(E) Embodiment An embodiment of the bass reproduction speaker system according to the present invention will be described with reference to FIGS. 1 to 3.

In the figure, 1 is a speaker enclosure, 2 is a speaker unit, 3 is an acoustic tube 24 formed continuously from the back side 2a of the speaker unit 2, and is a partition plate provided to form the acoustic tube 3, 5 is a speaker unit 2 A vacant room 6 is provided on the front side 2b of the speaker enclosure 1.
A port 8 connecting the two is an opening of the acoustic tube 3, and the acoustic tube 3 and the empty chamber 5 are connected at this opening 8.

Further, the resonant frequency of the port 6 and the frequency at which a half wavelength is applied to the acoustic tube 3 are configured to be substantially the same.

In the bass reproduction speaker configured as described above, the sound emitted from the front surface 2b of the speaker unit 2 is guided to the empty chamber 5.
Bass reflex speaker system B consisting of and port 6
Therefore, the bass range near the resonant frequency of port 6 is almost in reverse phase and is transmitted to the outside 7 of the speaker enclosure 1.
guided by.

On the other hand, the sound emitted to the rear side 2a of the speaker unit 2 is guided to the opening 8 of the acoustic tube 3 through the acoustic tube 3, but the frequency at which the half wavelength is carried by the acoustic tube 3 of this bass reproduction speaker system is The nearby bass range is once again in opposite phase at the opening 8.

Then, since the sound passing through the sound tube 3 is also added to the bass reflex type speaker system B, the sound on the front side 2b side of the speaker unit 2 and the sound on the rear side 2a are added together in this bass reflex type speaker system B. Furthermore, the bass range is efficiently reproduced.

In particular, in the present invention, the resonant frequency of the port 6 and the frequency at which a half wavelength is placed on the acoustic tube 3 are configured to be substantially the same, so that the reproduction efficiency is significantly improved.

Now, the sound radiated into the acoustic tube 3 is most emphasized at a frequency whose wavelength is twice the length of the acoustic tube 3, and is radiated outside the opening 8 (empty room 5). Frequencies other than those above are also radiated to the outside of the aperture 3. Among these, sounds with frequencies whose wavelength is an integral multiple of the length of the acoustic tube 3 are out of phase, canceling out the sounds on the front side 2b of the speaker unit 2 and attenuated, but other sounds are also attenuated. Since it is guided to the empty chamber 5, the high-frequency components in particular are efficiently attenuated by the filter effect of the empty chamber 5.

In addition, since the empty chamber 5 and the opening 8 of the acoustic tube 3 are connected, the acoustic tube 3 becomes equivalently longer when viewed from the acoustic tube 3, and the acoustic tube 3 becomes equivalently longer when viewed from the empty chamber 5. Although the volume of the empty chamber 5 becomes larger, the bass reproduction band becomes wider.

2 and 3 show other embodiments of the invention;
In the figure, by providing the partition plate 4A, the acoustic tube 3
In addition, another acoustic tube 3A is provided, which connects the respective openings 8.8A to the two acoustic tubes 3.3 with the empty chamber 5.

In FIG. 3, two speaker units are provided, one speaker unit 2 is provided with an acoustic tube 3, and another acoustic tube 3^ is formed for the other speaker unit 2A, and the two acoustic tubes 3.3 are connected to each other. The openings 8.8A and the empty chambers 5 are connected to each other.

In addition, in FIGS. 2 and 3, the lengths of the acoustic tubes 3°3^ may be the same or different.

Further, the number of vacant rooms may be divided into two instead of one.

(f) Effects of the Invention Since the bass reproduction speaker according to the present invention is configured as described above, the following effects can be achieved.

■It is possible to significantly attenuate unnecessary high-frequency components.

■It is possible to improve bass reproduction efficiency.

■Since the speaker system has only one opening, the degree of freedom in installation location is improved.

In addition, it has excellent features such as a simple structure, low cost, and easy implementation.

[Brief explanation of the drawing]

1 to 3 show an embodiment of a bass reproduction speaker system according to the present invention, FIG. 1 is a sectional view, and FIGS. 2 and 3 are sectional views showing other embodiments of the invention. be. FIG. 4 is a sectional view showing a conventional embodiment. Explanation of main symbols 1: Speaker enclosure 2 Speaker enclosure 3: Acoustic tube 4: Partition plate 5: Vacant room 6: Port 8, opening

Claims (2)

[Claims] 1. In a bass reproduction speaker system consisting of an acoustic tube formed continuously from the back of the speaker unit, a cavity provided in the front of the speaker unit, and a bass reflex port provided in this cavity, the opening of the acoustic tube 1. A speaker system for bass reproduction, characterized in that the speaker system is configured such that the section is connected to a vacant room. 2. Claim 1 characterized in that the resonant frequency of the port of the bass reflex and the frequency at which a half wavelength is placed on the acoustic tube are substantially the same.
The speaker system for bass reproduction described.