JP2010081316A - Loudspeaker system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a loudspeaker system for bass in which reactive vibration of a diaphragm vibrating a cabinet or an overall loudspeaker system is reduced during operation and bass range characteristics is enhanced. <P>SOLUTION: A pair of or a plurality of loudspeaker units are mechanically coupled at a back side and electrically connected in such a way that a sum of vectors of mutual reactive vibration during operation becomes zero, thereby reducing vibration of an overall loudspeaker system. At the same time, a duct-incorporated cabinet or a sealed cabinet is mounted on a front side of each loudspeaker unit to attenuate middle and treble range components. Furthermore, a resonant frequency ratio between the cabinet and the duct in a duct-incorporated type and a capacity ratio of the cabinet in a sealed type are each set to 1:1 to 1:3 to resonate a bass range, thereby enhancing bass characteristics. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a speaker system used as an acoustic system with high sound quality and particularly excellent low-frequency characteristics by being incorporated in or combined with a television receiver or the like.

  Conventionally, while a speaker system built in a television receiver has been reduced in size to adapt to the size of a limited installation space, in addition to the development of video tapes and video discs, along with the remarkable progress of video technology, In recent years, there has been a demand for higher sound quality for reproduced sound. However, the diameter of the speaker is also restricted due to dimensional restrictions, and sufficient progress has not been made in improving the sound quality especially in the low sound range.

  In a phase inversion speaker system for the purpose of improving the low sound range, acoustic radiation means such as a port or a duct is provided on the front baffle plate of a closed cabinet, and a part of the sound radiated to the back of the speaker unit is passed through the duct. Since the sound is emitted in phase with the sound emitted through the front, the bass reproduction range is expanded. A speaker system in which the inside of the cabinet is divided into two chambers by a partition plate, two speaker units are attached to the partition plate on one chamber side, and a duct is provided in both chambers to constitute an acoustic series double resonance circuit. Is known, and the bass characteristic is arbitrarily set by selectively combining the resonance frequencies of the ducts. However, in this configuration, the resonance system is 2 or less, the degree of freedom in design is small, and there is a limit to the range of characteristics that can be set. Therefore, a speaker system that improves these points with a relatively simple configuration is provided. There is an attempt (see, for example, Patent Document 1). According to this attempt, the front or back surface of each diaphragm of a plurality of speaker units is covered with a cabinet having a predetermined volume, and the other surface is covered with one common cabinet having a predetermined volume. By providing this duct, a multiple resonance circuit is formed as a whole, and a speaker system having a frequency characteristic that is the sum of acoustic output signals radiated from all ducts can be obtained.

  There is another proposal for obtaining high-quality sound capable of reproducing particularly rich bass in a bass-reflex type speaker device having a duct that inverts the phase of sound radiated from the back of the speaker unit and radiates to the outside (for example, Patent Document 2). According to this proposal, a part of the duct is formed of a metal plate, the volume of the duct is changed by changing the length and shape thereof, the resonance frequency in the low frequency range of the speaker box by the duct is changed, and the speaker device The low frequency range characteristic can be made a desired characteristic.

JP-A-3-22797 Japanese Patent Laid-Open No. 10-117311

  In the conventional speaker system of the type described above, the entire cabinet vibrates due to the reaction of vibration during the operation of, for example, a cone-type diaphragm used for a speaker unit having a relatively large aperture that emphasizes reproduction in the low frequency range. Vibrates the entire sound system of equipment such as a television receiver that incorporates or is used in combination, generates mechanical vibrations that are different from the playback sound, or vibrates the television receiver and shakes the image. There is a problem that causes image quality and deteriorates image quality. However, suppression of this vibration has to rely on mechanical suppression means, and in that respect it has been difficult to simplify the structure. In particular, in a speaker system including a resonance system in an acoustic radiation system such as the above-described phase inversion type or bass reflex type, the vibration of the entire cabinet has a great influence on the reproduction acoustic characteristics.

  Accordingly, the present invention reduces the reaction vibration of the vibration of the diaphragm during the operation of the speaker unit and suppresses the vibration of the entire speaker system, particularly in the low frequency range, in the speaker system including the resonance system in the acoustic radiation system. An object of the present invention is to provide a loudspeaker system capable of obtaining high-quality reproduced sound with improved sound quality and eliminating or simplifying means for suppressing vibration due to reaction vibration.

In order to achieve the above object, a speaker system according to the present invention of claim 1 is a speaker system in which front surfaces of a plurality of speaker units are covered with a cabinet, and the emitted sound is inverted in phase and radiated to the outside. The units are mechanically coupled to each other on the back surface, and the peripheral surfaces of the speaker units coupled to the back surface are opened to form an acoustic radiation unit. The cabinet is a tubular body that is provided on the front surface of each speaker unit so as to extend in the axial direction of the speaker unit. Each cabinet includes at least one tubular duct having one end opened at the outer end of the cabinet and the other end opened into the cabinet, and the ratio of resonance frequencies of the respective cabinets and ducts is 1: 1. Set to the range of ~ 1: 3, each speaker unit has its reaction vibration Characterized in that it is arranged and connected such that the sum of the vector is zero (0).
According to the solution of claim 2, the speaker system according to claim 1 is characterized in that the outer end of the duct is located on the end surface in the longitudinal direction of the cabinet and the inner end is provided to face the front surface of the speaker unit. To do.
According to the means of claim 3, the speaker system according to claim 1 is provided in such a manner that each cabinet of each speaker unit communicates with each other via a communication portion provided on a part of the peripheral surface of the speaker unit combination. The duct is provided perpendicular to the longitudinal direction of the cabinet at the communicating portion.
According to a fourth aspect of the present invention, the speaker system according to the first aspect is characterized in that a diffuser is provided in the acoustic radiation portion.
According to a fifth aspect of the present invention, the speaker system according to the first aspect includes a fixture receiving member for the fixture of the television stand column portion in the acoustic radiation portion.
According to a sixth aspect of the present invention, the speaker system according to the first aspect is characterized in that the plurality of speaker units and the cabinet are radially arranged around a common coupling member.
According to the means of claim 7, in the speaker system according to claim 1, at least two pairs of speaker units are provided in parallel, the cabinet is provided in common on the front face of at least two adjacent speaker units, and the duct is It is arrange | positioned in the approximate center of the longitudinal direction of a common cabinet, It is characterized by the above-mentioned.
According to the eighth aspect of the present invention, the speaker system according to any one of the first to seventh aspects is characterized in that the speaker units are coupled to each other or to a common coupling member by an adhesive on the back side bottom surface. .
According to the ninth aspect of the present invention, in the speaker system according to any one of the first to seventh aspects, the speaker units form a pair, and each pair is fastened and coupled by screw means penetrating the central axis. It is characterized by.
According to the means of claim 10, in the speaker system in which the front surfaces of the plurality of speaker units are sealed with a cabinet and the emitted sound is phase-inverted and radiated to the outside, the plurality of speaker units are mechanically coupled to each other on the back surface. Then, the peripheral surfaces of the speaker units connected to the back surface are opened to form an acoustic radiation portion, and the cabinets are formed of a cylindrical body or a box-like body provided on the front surface of each speaker unit so as to extend in the axial direction of the speaker unit. Is set in the range of 1: 1 to 1: 3, and the speaker units are arranged and connected so that the sum of the vectors of the reaction vibrations is zero (0).

  When at least one pair of speaker units is mechanically coupled to each other on the back side, each front side is covered with a sealed cabinet, a duct is provided in the cabinet, and the cabinet is opened at one end of the duct, the cabinet and the duct When the resonance frequency ratio is set to a range of 1: 1 to 1: 3, and the cabinet is a closed type without providing a duct, the volume ratio of each cabinet is set to a range of 1: 1 to 1: 3. As a result, the bass characteristic is improved. Furthermore, by arranging and connecting each speaker unit so that the sum of the vectors of the respective reaction vibrations becomes zero, vibrations generated from the speaker units can be canceled, and the improved low-frequency characteristics are improved. It is demonstrated without being affected.

  Several examples are shown in FIGS. 1 to 9 as the best mode of the speaker system according to the present invention, and will be described below.

  FIG. 1 is a longitudinal sectional view showing a first embodiment of the basic configuration of a speaker system according to the present invention, and in the center, the back side, that is, the bottom face of a magnetic circuit is brought into contact with each other so that the central axis is aligned and integrated. A pair of speaker units 1a and 1b coupled to each other is arranged, and both sides of the speaker units 1a and 1b are hollow cylindrical cabinets 2a and 2b whose front sides 1c and 1d, that is, outer sides of the diaphragms are closed and whose outer ends are closed. Cover with each of. For the connection between the speaker units 1a and 1b, it is desirable to bond with the adhesive applied to the bottom surface of each magnetic circuit, or to fasten with a screw means such as a screw or a bolt nut that penetrates the central axis of both units.

  The pair of speaker units 1a and 1b coupled on the back side, that is, coupled in the opposite directions to each other, have a zero (0) sum of the vibration vectors of the speaker units due to reaction during operation and cancel each other out. Thus, the occurrence of vibration of the entire cabinet due to the reaction of vibration of the diaphragm is suppressed.

Further, in order to improve the low frequency characteristics of the speaker system, the front side 1c, 1d, which is the outer side of the diaphragm of the pair of speaker units 1a, 1b coupled in opposite directions as described above, The open inner ends of the cylindrical cabinets 2a and 2b having closed ends are attached, and the speaker unit front side 1c and 1d are sealed. As a result, the mid-high range component is attenuated inside the cabinets 2a and 2b. For the low sound range, each of the hollow cylindrical ducts 4a and 4b having a diameter smaller than that of the cabinet is opened at one end 4c and 4e at the outer end of the cabinet, and the other end 4d, 4f is installed so as to open toward the speaker unit front face 1c and 1d, and the ratio of the resonance frequency calculated for the cabinet and the duct is set in the range of 1: 1 to 1: 3, thereby mainly radiating from the duct. The low frequency range to be generated can be a high-quality resonance sound with little distortion. The following calculation formula is used to calculate the resonance frequency fb of the duct.
fb = √ ((30000 × S) / (V × (L + 0.825√ (S))))
Here, S represents the area of the duct (cm ² ), V represents the volume of the cabinet (lit.), and L represents the length of the duct (cm).

  The sound radiation unit 3 is formed by opening the periphery of the combined unit of the speaker units 1a and 1b, the mid-high range component radiated to the front of the speaker unit is attenuated in both cabinets, and the low range component resonating with the duct is the duct. Although it is radiated from the opening end, the entire sound range component coming out on the back side is resonated and radiated by the acoustic radiation unit 3.

  FIG. 9 shows the characteristics of the reaction vibration generated from the back-coupled speaker unit measured at the middle position in the longitudinal direction of both cabinets 2a and 2b in the speaker system of the present invention according to Example 1 of FIG. As a result of sweeping 500 Hz, the amplitude value at the measurement position was almost zero over the entire period. On the other hand, the similar vibration characteristic of FIG. 10 measured at the outer periphery of the speaker unit opposite to the duct of the conventional speaker system including a single speaker unit and a duct extending perpendicularly to the axis thereof is already 20 Hz. Remarkable amplitude values are shown. 11 and 12 show frequency characteristic curves in the entire sound range of the speaker system of Example 1 according to the present invention of FIG. 9 and the conventional speaker system used for the measurement of FIG. 10, and can be seen in FIG. Thus, according to the present invention, the improvement in the low frequency range and the attenuation in the middle and high frequency range are clear.

  FIG. 2 shows the speaker system according to the second embodiment of the present invention. The difference in configuration from the first embodiment is that each of the cabinets 2a and 2b does not have the ducts 4a and 4b. It is the point which sealed. In this case, by setting the volume ratio of the pair of speaker units 1a and 1b in the range of 1: 1 to 1: 3, the mid-high range component is attenuated in the sealed cabinet, but the low range component is the both cabinets. And is radiated from the acoustic radiation unit 3 together with the back side radiation sound.

  FIG. 3 shows another embodiment of the speaker system of the second embodiment. Here, the duct 4b of the first embodiment is provided in one cabinet 2b to open the outer end, but the other cabinet 2a is kept sealed. If the volume ratio of the second embodiment is applied to the closed cabinet 2a and the resonance frequency ratio of the first embodiment is applied to the cabinet 2b with an opening duct, a composite low frequency characteristic can be obtained.

  FIG. 4 shows a speaker system according to a third embodiment of the present invention, in which the independent cabinets 2a and 2b shown in the first and second embodiments are increased in diameter or width, and the back-coupled speaker units 1a and 1b located in the center are arranged. The two cabinets 2d and 2e are communicated with each other by the communication portion 2c provided on the side. Here, a duct 4g extending in a direction orthogonal to the axis of the speaker units 1a and 1b is provided in the communication portion 2c, and the communication space in the cabinets 2d and 2e is unsealed via the duct 4g. Therefore, although the resonance frequency ratio of the first embodiment is applied, a closed type without providing a duct may be used, and the volume ratio of the second embodiment may be applied.

  FIG. 5 shows an embodiment that can be applied in common to Examples 1 and 2 and, if desired, can also be applied to Example 3. The speaker system of the present invention has one side surface of a central speaker unit combination. And a diffuser 5 comprising a reflecting plate 5a for returning the radiated sound to the speaker unit combination side and a diffusion cone 5b for diffusing the sound and the radiated sound from the reflecting plate attached to the opposite side surface. Give direction to sound and improve acoustic characteristics.

  FIG. 6 shows an embodiment applicable to Examples 1 and 2, and the speaker system of the present invention receives a corresponding portion of the fixture 8 provided in the column portion of the television stand 7 of the television receiver used in combination. A fixture receiving member 6 is provided. Therefore, the speaker system of the present invention can be easily mounted and used on the lower front part of the television receiver.

  In the speaker system according to the fourth embodiment of the present invention shown in FIG. 7, the back surfaces of the three speaker units 1e to 1g are bonded and fixed to respective surfaces of a common coupling member 9 having a regular triangular cross section in this case. The open ends of three cabinets 2f to 2h similar to those of the first embodiment are attached to the front surface of each speaker unit, and are arranged radially at equal intervals. This radial array can be formed by a desired plurality of speaker units and cabinets if a common coupling member 9 having a regular polygonal cross section with a desired number of corners is used. Needless to say, the connection described in the first embodiment for canceling the vibration of the speaker unit due to the reaction and the resonance frequency ratio or the volume ratio for improving the bass characteristic are applied.

  In Example 5 of FIG. 8, a plurality of pairs of back-coupled speaker units and cabinets attached to the front surface thereof are arranged in parallel. In the drawing, two pairs of speaker units 1h, 1i and 1j, 1k coupled to the back are juxtaposed in contact with each other, and cabinets 2i, 2j communicating with the two front surfaces on each side of the two speaker units arranged respectively. Mounted. As desired, these cabinets are either a ducted type or a closed type without a duct, and a desired value of the resonance frequency ratio or volume ratio is set and a connection for canceling the reaction vibration is made accordingly.

1 is a longitudinal sectional view of a speaker system according to a first embodiment of the present invention. The longitudinal cross-sectional view of the speaker system by Example 2 of this invention. The longitudinal cross-sectional view of the speaker system of embodiment common to Example 1 and 2. FIG. The longitudinal cross-sectional view of the speaker system by Example 3 of this invention. The longitudinal cross-sectional view of the speaker system of embodiment which can be applied to Examples 1-3. The longitudinal cross-sectional view of the speaker system of Example 1 of the state attached to the television stand pillar part. The longitudinal cross-sectional view of the speaker system by Example 4 of this invention. The longitudinal cross-sectional view of the speaker system by Example 5 of this invention. FIG. 3 is a reaction vibration characteristic diagram of a low sound range by the speaker system of the first embodiment. The low-range reaction vibration characteristic figure by the speaker system of a prior art example. The frequency characteristic figure of the whole sound range by the speaker system of Example 1. FIG. The frequency characteristic figure of the whole sound range by the speaker system of a prior art example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1a-1k Speaker unit 2a-2j Cabinet 3 Sound radiation | emission part 4a-4g Duct 5 Diffuser 5a Reflector 5b Diffusion cone 6 Fixture receiving member 7 Television stand 8 Fixture 9 Coupling member

Claims (10)

In a speaker system that covers the front surfaces of a plurality of speaker units with a cabinet and radiates sound by inverting the phase of the emitted sound,
A plurality of speaker units are mechanically coupled to each other on the back surface, and the peripheral surfaces of the speaker units coupled to the back surface are opened to form an acoustic radiation portion, and the cabinet is provided in a front surface of each speaker unit so as to extend in the axial direction of the speaker unit. Each cabinet is provided with at least one tubular duct having one end opened at the outer end of the cabinet and the other end opened into the cabinet, and a ratio of resonance frequencies of the respective cabinets and ducts. A speaker system, wherein the speaker system is set in a range of 1: 1 to 1: 3, and each speaker unit is arranged and connected so that a sum of vectors of reaction vibrations is zero (0).   The speaker system according to claim 1, wherein an outer end of the duct is located on an end surface in a longitudinal direction of the cabinet, and an inner end is provided to face the front surface of the speaker unit.   Each cabinet of each speaker unit is provided so as to communicate with each other via a communication portion provided on a part of the peripheral surface of the speaker unit combination, and the duct is provided at the communication portion so as to be orthogonal to the longitudinal direction of the cabinet. The speaker system according to claim 1, wherein:   The speaker system according to claim 1, further comprising a diffuser in the acoustic radiation unit.   The speaker system according to claim 1, further comprising a fixture receiving member for the fixture of the TV stand column portion in the acoustic radiation portion.   The speaker system according to claim 1, wherein the plurality of speaker units and the cabinet are arranged radially around a common coupling member.   Wherein at least two pairs of speaker units are provided in parallel, the cabinet is provided in common on the front surface of at least two adjacent speaker units, and the duct is disposed substantially at the center in the longitudinal direction of the common cabinet, The speaker system according to claim 1.   The speaker system according to any one of claims 1 to 7, wherein the speaker units are respectively coupled to each other or to a common coupling member by an adhesive on the back side bottom surface.   The speaker system according to any one of claims 1 to 7, wherein the speaker units form a pair, and each pair is fastened and coupled by screw means penetrating the central axis. In the speaker system in which the front surfaces of a plurality of speaker units are sealed with a cabinet and the sound emitted is phase-inverted and radiated to the outside.
A plurality of speaker units are mechanically coupled to each other on the back surface, and the peripheral surfaces of the speaker units coupled to the back surface are opened to form an acoustic radiation portion, and a cabinet is provided on the front surface of each speaker unit so as to extend in the axial direction of the speaker unit. The volume ratio of each cabinet is set in a range of 1: 1 to 1: 3 so that each speaker unit has a sum of vectors of reaction vibrations of zero (0). A speaker system characterized by being arranged and connected.

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