JPH04287497A - Speaker system - Google Patents

Abstract

PURPOSE:To realize the speaker system with simple structure by simplifying a low frequency sound tuning mans for the entire speaker system. CONSTITUTION:The system is provided with two 1st resonance bodies 10, 12 or over formed cylindrical, whose one end is fitted with a speaker 54, Whose other end is provided with a low frequency sound tuning ducts 20, 22 linked to the inside and a 2nd resonator 24 formed cylindrical, to which the ducts 20, 22 of the 1st resonators 10, 12 are fitted projectingly and having an opening 26 sounding the tuned sound externally.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a speaker system, and more particularly to a speaker system having a structure in which the low range of sounds emitted from the back of the speaker is tuned and emitted to the outside.

0002

2. Description of the Related Art Conventionally, there are various types of speaker systems that are designed to tune the low range of sound emitted from a speaker and emit it to the outside. In either type, one set of bass tuning means is provided for each speaker or set of speakers.

0003

[Problems to be Solved by the Invention] However, conventional speaker systems have the following problems. Since one set of bass tuning means is provided for each speaker or set of speakers, the speaker system becomes expensive due to an increase in the number of parts and assembly steps. There are challenges. Therefore, an object of the present invention is to simplify the bass tuning means of the entire speaker system and provide a speaker system with a simple structure.

0004

[Means for Solving the Problems] In order to solve the above problems, the present invention has the following configuration. That is, two or more first resonators each having a cylindrical shape, a speaker attached to one end, and a bass tuning duct communicating with the inside at the other end; and a second resonator having an opening for emitting the tuned sound to the outside, into which the duct of each first resonator is installed. shall be.

[0005]

[Action] The action will be explained. Since only one second resonator is required to constitute the bass tuning means, the structure of the entire speaker system can be simplified.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings. FIG. 1 shows a plan sectional view of a speaker system for a car stereo. First, the configuration will be explained. 10 and 12 are first resonators. First resonator 10
, 12 is an L-shaped cylinder with both ends open. A speaker 14 is fixed to the tip of the first resonator 10, 12 with the front surface facing outward using appropriate fixing means (not shown) such as bolts. At the rear ends of the first resonators 10, 12, tapered cylindrical parts 16, 18 are formed, the inner diameter of which gradually decreases toward the rear end. Small-diameter first ducts 20 and 22 are provided further toward the rear ends of the tapered cylindrical portions 16 and 18. The first ducts 20 and 22 are provided for tuning the low range of sounds emitted from the back surface of the speaker 14 by utilizing the Holmhertz phenomenon, which is resonance. The inner diameters of the first ducts 20 and 22 are determined by selecting appropriate values based on the relationship between the (bass) frequency to be tuned and the diameter of the speaker 14. The length of the first ducts 20, 22 is also determined by the frequency to be tuned. The longer the length of the first ducts 20, 22, the higher the frequency to be tuned. In this embodiment, the tapered cylindrical portions 16 and 18 of the first resonators 10 and 12, the first duct 20,
22 is formed integrally with the main body, for example, from a vinyl chloride pipe, but they may be formed separately and assembled as the first resonator.

[0007] 24 is a second resonator. Second resonator 24
is a cylinder with both ends open. The rear end portions of the first resonators 10 and 12 enter into the interior from both open ends of the second resonator 24, and are attached by suitable fixing means (not shown). The first resonator 10 is disposed on the outer peripheral surface of the second resonator 24.
, 12 is provided with an opening 26 for emitting the bass tuned to the outside. In this embodiment, the second resonator 24
It is also made of PVC pipe. 28 is the second
It is a duct and is formed into a cylindrical shape. Second duct 28
corresponds to the opening 26 of the second resonator 24, and the second resonator 2
4, and is installed to communicate with the inside of speaker 1.
4 in the front direction. The inner diameter and extension length of the second duct 28 are equal to the inner diameter and length of the first ducts 20 and 22. This is the first duct 20, 22
This is because by further tuning the bass tuned by the second duct 28, a sound closer to the intended purpose can be tuned. Note that the opening 26 is located at the second resonator 2.
The reason why the openings are perpendicular to the openings at both ends of the resonators 10 and 12 is that even in the sound tuned by the first ducts 20 and 22 of the first resonators 10 and 12, highly linear high frequency components remain. This is to reduce high frequency components of sound emitted from the openings 26 by opening the openings 26 in a direction perpendicular to the length direction of the first ducts 20, 22. here,
A method for determining the inner diameters and lengths of the first ducts 20, 22 and the second duct 28 will be explained. The volume of the speaker system of the example is V, and the effective vibration radius of the speaker 14 is a.
, the sharpness of the lowest resonance frequency is k, and the equivalent mass of the vibration system is m0
, the lowest resonant frequency is f0, then V = (3
55*a*a*a*a)/(k*m0 *f0 *f0
) (Note that * is an arithmetic sign indicating a product). Also,
The length of the first ducts 20, 22 and the second duct 28 is l
, the opening area is A, and the tuning frequency is fob, then l = (30000*A)/(fob*fob*
V). The theoretical inner diameters and lengths of the first ducts 20, 22 and the second duct 28 are determined using the above two equations, and then, in practice, fine adjustments are made using human hearing to determine the final values.

A filter 30 is made of rubber, sponge, or the like. The filter 30 is sandwiched between the cylindrical bodies 32 and 34 at the center of the second resonator 24 . The positions of the cylinders 32 and 34 are fixed by appropriate fixing means (not shown). The filter 30 is the first duct 20,
The opening 2 absorbs the high frequency components of the sound emitted from the opening 2.
6 is provided in order to suppress the emission of the high frequency component. Note that the filter 30 does not necessarily need to be provided, and may be omitted if high frequency components are sufficiently removed by the first ducts 20, 22, etc. The material, thickness, etc. of the filter 30 may be appropriately selected depending on the frequency to be absorbed. The portions of the cylindrical bodies 32 and 34 corresponding to the opening 26 of the second resonator 24 are cut into a shape that makes it impossible to close the opening 26.

Next, the operation of the speaker system configured as described above will be explained. When the speaker 14 sounds, high frequency components are mainly emitted from the front surface of the speaker 14. Since the high frequency component has good directionality, it is necessary to clearly separate it into left and right to enhance the stereo effect, so it is emitted from the front of the speaker 14. On the other hand, since low frequency components have low directionality, there is no need to clearly separate them into left and right. Therefore, the sound emitted from the back of both speakers 14 is transmitted to the first resonators 10 and 1.
2, the bass is tuned in the first ducts 20 and 22, and only the tuned bass is transmitted through one second resonator 24.
sent to. In the first resonator 10, 12, the high frequency component with straight propagation is first removed at the L-shaped bent part, and then tuned in the first ducts 20, 22, so that the sound entering the second resonator 24 is Almost all high frequency components are removed. Then, high frequency components are further removed by the filter 30, the sound enters the second duct 28 through the opening 26, is tuned for bass once again, and is emitted from the second duct 28.

Next, another embodiment will be described with reference to FIGS. 2 and 3. The example in Figure 2 (plan view) is a linear first
This is an example in which two speakers 54 are attached to the front sides of each of the resonators 50 and 52. On the other hand, the example shown in FIG. 3 (front view) is an example in which the first resonators 70 and 72 and the second resonator 74 are connected at right angles. As for the shape of the speaker system, any shape can be adopted depending on the structure of the automobile or the like to which it is installed. The speaker system of this embodiment has a simple structure and is easy to process and assemble. Also, since there is no baffle board, the sound is clear. Various preferred embodiments of the present invention have been described above, but the present invention is not limited to the above-mentioned embodiments. For example, the number of first resonators may be three or more, and the number of first resonators may be three or more, It goes without saying that many modifications can be made without departing from the spirit of the invention, such as the invention being usable as a speaker system for other audio equipment.

[0011]

[Effects of the Invention] When the speaker system according to the present invention is used, only one second resonator is required to constitute the bass tuning means, thereby reducing the number of parts and the number of assembly steps. This makes it possible to provide an inexpensive speaker system.

[Brief explanation of the drawing]

FIG. 1 is a plan sectional view showing an embodiment of a speaker system according to the present invention.

FIG. 2 is a plan view showing another embodiment of the speaker system according to the present invention.

FIG. 3 is a front view showing another embodiment of the speaker system according to the present invention.

[Explanation of symbols]

10 First resonator 12 First resonator 14 Speaker 20 First duct 22 First duct 24 Second resonator 26 Opening 50 First resonator 52 First resonator 54 Speaker 70 First resonator 72 First resonator 74 Second resonator

Claims (1)

[Claims] 1. Two or more first resonators formed in a cylindrical shape, each having a speaker attached to one end and a bass tuning duct communicating with the interior at the other end; A second resonator is formed in a cylindrical shape, into which the duct of each first resonator enters and is attached, and has an opening for emitting tuned sound to the outside. A speaker system characterized by the following.