JP2010189841A - Sound diffuser and method for diffusing sound - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a sound diffuser which is installed in a room so as to adjust a sound. <P>SOLUTION: A columnar diffuser, in which a plurality of cylinders different in diameter are arranged, is used for mid-to-high-frequency ranges. A cylindrical diffuser using a material with a great internal loss is used for a low-frequency range. The columnar diffuser is transported or stored by being housed inside the cylindrical diffuser. Additionally, the cylindrical diffuser and the columnar diffuser can also be used in a combined or separated state. When the cylindrical diffuser and the columnar diffuser are separated from each other, each of them is arranged in an optimum location in the room, so as to enable the sound to be adjusted in a wide area. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an acoustic diffuser and an acoustic diffusion method, and more particularly to a diffuser and an acoustic diffusion method for adjusting sound by freely arranging in a room.

In recent years, video and audio sources such as broadcasting and package media have become HDTV (high definition television) resolution, and at the same time, the audio-visual boom has been rising.
In these HDTV sources, audio is also recorded in a more sophisticated method than before. For example, it records dense audio with a sampling frequency of 96 KHz or 192 KHz and a dynamic range of 24 bits.
However, in a living room in a normal house, it is difficult to obtain a good sound field due to space and design limitations.
In particular, it is important to suppress wall vibrations due to excessive next-order reflection (flutter echo), standing waves, and excessive bass sounds that occur between opposing wall surfaces in the room. In order to obtain a good sound field, it is important to adjust the initial reflected sound and the reverberant sound so that the sound spread can be felt even in a room with a finite volume.
For this reason, conventionally, acoustic panels made of a sound absorbing material that is placed in a room or attached to a wall or ceiling in order to adjust the sound in the room are commercially available.

Here, as a conventional acoustic panel, referring to Patent Document 1, an acoustic diffusion panel that can easily adjust the sound environment in the horizontal direction is described (hereinafter referred to as Conventional Technique 1).
The acoustic panel of prior art 1 includes two support legs that are erected at regular intervals, and two acoustic panels that are supported by the respective support legs. This acoustic panel is connected so that two acoustic panels can be freely opened in the horizontal direction. Each acoustic panel is supported by a support leg via a slide mechanism that slides in the horizontal direction, and a rotation mechanism that rotates the acoustic panel in the horizontal direction is provided on each support leg. And the action surface which reflects and absorbs a sound is formed in the front surface of an acoustic panel, and the acoustic panel is supported by the support leg in the back surface.
By using the acoustic panel of prior art 1, it is possible to finely adjust the direction of sound absorption and reflection by opening and closing the acoustic panel like a folding screen, and the acoustic panel is supported via a slide mechanism and a rotation mechanism. Since it is supported by the legs, it can be opened and closed smoothly. Therefore, flutter echoes and standing waves can be reduced by adjusting the angle and installation location.

JP 2006-30995 A

  However, the acoustic panel of the prior art 1 has the characteristics of the treble, middle and low frequencies determined by its material, shape and dimensions, and the position in the room related to flutter echo and standing wave differs depending on the high and low frequencies. There was a problem that it was not possible to cope with it. For this reason, when only one acoustic panel was used, only an insufficient acoustic improvement effect was obtained. Therefore, it is necessary to adjust the sound field by installing a number of acoustic panels in the room for high and low sounds, and there is a problem that costs increase.

  This invention is made | formed in view of such a condition, and makes it a subject to eliminate the above-mentioned subject.

The acoustic diffuser of the present invention includes a columnar diffuser for middle and high frequencies in which a plurality of columns having different diameters are arranged,
And a cylindrical diffuser for a low frequency range, and the columnar diffuser is configured to be retractable or separable inside the cylindrical diffuser.
In the acoustic diffuser of the present invention, the cylindrical diffuser is configured to be extendable and contracted, and the height is changed to adjust the degree of absorption and diffusion of bass.
In the acoustic diffuser of the present invention, the cylindrical diffuser includes a resonance hole and / or an acoustic inlet.
The acoustic diffuser of the present invention is characterized in that the tubular diffuser is configured to be able to incorporate a sound absorbing material.
In the acoustic diffuser of the present invention, the cylindrical diffuser is used as a packing material.
The acoustic diffuser of the present invention is characterized in that the columnar diffuser has a plurality of cylinders having different diameters arranged in a curved shape.
In the acoustic diffusion method of the present invention, a columnar diffuser in which a plurality of columns having different diameters and a cylindrical cylindrical diffuser are combined and / or separated and arranged in a room, and the columnar diffuser It is characterized by diffusing the mid-high range and diffusing and absorbing the low range by the cylindrical diffuser.

  According to the present invention, it is possible to separate the columnar diffuser that diffuses the mid-high range and is acoustically transparent in the low range, and the cylindrical diffuser for the low range, so that the frequencies of the mid-high range and the low range can be separated. The band can be provided with an acoustic diffuser that can optimally adjust the acoustics of the room.

It is a conceptual diagram of the cylindrical diffuser 10 and the columnar diffuser 20 in the acoustic diffuser 1 which concerns on embodiment of this invention. 1 is a plan view of a cylindrical diffuser 10 and a columnar diffuser 20 in an acoustic diffuser 1 according to an embodiment of the present invention. 1 is a front view of a cylindrical diffuser 10 and a columnar diffuser 20 in an acoustic diffuser 1 according to an embodiment of the present invention. 1 is a bottom view of a cylindrical diffuser 10 and a columnar diffuser 20 in an acoustic diffuser 1 according to an embodiment of the present invention. 1 is a side view of a cylindrical diffuser 10 and a columnar diffuser 20 in an acoustic diffuser 1 according to an embodiment of the present invention. It is a conceptual diagram which shows the bass adjustment of the cylindrical diffuser 10 which concerns on embodiment of this invention. It is a conceptual diagram which shows the arrangement | positioning method to the room of the acoustic diffuser 1 which concerns on embodiment of this invention. It is a figure which shows distribution of the sound field of the comparative example 1 which does not use the cylindrical diffuser 10 which concerns on embodiment of this invention. It is a figure which shows distribution of the sound field of Example 1 using the cylindrical diffuser 10 which concerns on embodiment of this invention. It is sectional drawing of a structure without the adjustment part 130 of the cylindrical diffuser 10 which concerns on embodiment of this invention.

<Embodiment>
First, the outline of the configuration of the acoustic diffuser 1 according to the embodiment of the present invention will be described with reference to the conceptual diagram of FIG.
The acoustic diffuser 1 according to the embodiment of the present invention mainly includes a cylindrical diffuser 10 and a columnar diffuser 20.
The cylindrical diffuser 10 can mainly adjust a sound field in a low frequency range of a frequency of several hundred Hz or less. The columnar diffuser 20 can be used to adjust the sound field mainly in the middle to high frequency range (middle high frequency range) of about 1000 Hz or higher.
Specifically, the acoustic diffuser 1 according to the embodiment of the present invention can be used in a state where the columnar diffuser 20 is combined with the inside of the cylindrical diffuser 10.
Moreover, as shown in FIG. 1, the cylindrical diffuser 10 and the columnar diffuser 20 can be separated and placed in a room. Moreover, it is also possible to arrange | position the upper cylinder 110 and the lower cylinder 120 of the cylindrical diffuser 10 separately in a room.
In addition, the cylindrical diffuser 10 and the columnar diffuser 20 are not simply combined, but are configured to optimize the adjustable frequency band, and one unit optimally adjusts the sound for each frequency band of the room. be able to.
Hereinafter, the configuration of the acoustic diffuser 1 will be described in more detail with reference to the drawings.

  2 to 5, when the acoustic diffuser 1 is separated from the cylindrical diffuser 10 and the columnar diffuser 20, a plan view (FIG. 2), a front view (FIG. 3), and a bottom view (FIG. 4) A side view (FIG. 5) is shown. Since the right side view and the left side view are symmetrical, only the right side view is shown.

[Configuration of the cylindrical diffuser 10]
The cylindrical diffuser 10 is a separable cylindrical acoustic diffuser, and includes an upper column 110, a lower column 120, and an adjustment unit 130.
As the size of the cylindrical diffuser 10, for example, the upper surface or the lower surface can be configured to have a diameter of approximately 43 cm, and the overall height can be configured to be approximately 146 cm. Moreover, the height of the upper cylinder 110 can be configured to be about 73 cm, and the height of the lower cylinder 120 can be set to about 73 cm.
By providing such a large diameter, the cylindrical diffuser can be provided with sufficient reflection and sound absorption performance for a low frequency range of several Hz to several hundred Hz.

The cylindrical diffuser 10 is a relatively light material having a sound wave loss or internal loss on a sufficient surface, such as recycled paper such as cylindrical cardboard, a material obtained by solidifying recycled paper with a resin, nonwoven fabric, glass fiber, etc. Manufactured from materials. For example, in the case of corrugated cardboard, the cylindrical diffuser 10 may be a corrugated paper tube having a thickness of 2.5 mm. As will be described later, the thickness of the paper tube can be different between the upper cylinder 110 and the lower cylinder 120.
Since the cylindrical diffuser 10 is manufactured using such a material, the cylindrical diffuser 10 can be manufactured at a lower cost than the columnar diffuser 20.
For this reason, the cylindrical diffuser 10 can be delivered and used like a packing material with the columnar diffuser 20 inserted when delivered. Even when the cylindrical diffuser 10 is used as a packaging material, the sound absorption / reflection effect hardly changes even if the cylindrical diffuser 10 is slightly damaged or distorted because the wavelength of the bass sound is long. Moreover, since it is inexpensive, it can be easily returned and exchanged.
Furthermore, storing the columnar diffuser 20 inside the cylindrical diffuser 10 makes it easy to store, move, and carry the acoustic diffuser 1 when it is not used.
Note that the cylindrical diffuser 10 does not necessarily have a cylindrical shape, and may be an elliptical column, an arcuate column, a star column, or the like.

Here, each part of the cylindrical diffuser 10 will be described in more detail.
The upper cylinder 110 and the lower cylinder 120 are cylinders having a similar structure, and are respectively closed on the upper surface or the bottom surface with the same material as that of the side surface (peripheral wall). Further, a circular plate portion may be inserted for reinforcement.
The adjustment unit 130 is a cylinder that is made of the same material as the upper cylinder 110 and the lower cylinder 120 and is not closed (empty) at both ends. The adjustment unit 130 is about 0.1 to 0.5 mm smaller than the upper cylinder 110 and the lower cylinder 120, has a small diameter, has an appropriate elasticity, and is in contact with the upper cylinder 110 and the lower cylinder 120 so as to be supported from the inside by friction. Yes. In addition, regarding the diameter of this adjustment part 130, the clearance (margin) which does not have shaki between the upper cylinder 110 and the lower cylinder 120 should just be sufficient. The adjusting unit 130 may increase the frictional force using an elastomer or rubber, and may be configured to connect the upper cylinder 110 and the lower cylinder 120 with a wedge-shaped lock structure.
Moreover, the height of the adjustment part 130 can be set about 10 cm higher than the upper cylinder 110 or the lower cylinder 120, for example, can be comprised about 740 cm. Thereby, it can fix so that the lower surface of the upper cylinder 110 and the upper surface of the lower cylinder 120 may contact | connect. Further, as will be described later, the adjustment unit 130 can be used to adjust the length at which the upper cylinder 110 and the lower cylinder 120 are fixed, and to change the frequency of the bass that performs sound absorption and diffusion.

[Configuration of Columnar Diffuser 20]
The columnar diffuser 20 includes a top plate portion 210, a plurality of diffusion columns 220, and a base portion 230.
The columnar diffuser 20 is made of, for example, wood such as flame retardant wood for construction or solid wood, plastic that suppresses vibration, metal, etc., and mainly diffuses sound waves in the middle / high range by the diffusion column 220. Can create a natural sound field. The columnar diffuser 20 is acoustically “transparent” in the low sound range, and can pass sound waves in the low sound range behind without reflecting or diffusing. However, the effect of breaking the phase of the bass can be obtained when passing the bass behind. As the size of the columnar diffuser 20, for example, the long side in the plan view of FIG. 2 can be formed with a length of about 40 cm and a short side with a length of about 20 cm. As the size of the columnar diffuser 20, the height in the front view of FIG. 3 can be configured to be about 130 cm.

The columnar diffuser 20 uses a plurality of randomly arranged diffusion columns 220, and sound waves diffused and reflected from the diffusion columns 220 are diffused in all directions, front, rear, left, and right. For this reason, a natural sound spread can be obtained compared with the acoustic panel which mainly absorbs sound and reflects in a predetermined direction like the acoustic panel of the prior art 1.
In addition, the columnar diffuser 20 is not a wall material, but is mainly placed on the floor and adjusted to be used, for example, next to a speaker. For this reason, the size is relatively compact, and the position to be placed according to the sound field environment of the speakers and rooms can be freely changed, and the user can easily adjust the sound according to the settings, and a great sound improvement effect can be achieved. Obtainable.

Here, the structure of each part of the columnar diffuser 20 will be described in more detail.
The top plate portion 210 is a portion that supports the plurality of diffusion columns 220 at the upper portion, and is configured to open holes for allowing the plurality of diffusion columns 220 to pass through the wood, and to insert the plurality of diffusion columns 220 into the holes. In addition, as shown in the plan view of FIG. 2, the diffusion columns 220 are arranged in a plurality of rows in a curved shape like an elliptical arc with rounded ends. As a result, it is possible to provide a loose directionality that diffuses a large amount of sound waves in the convex direction of the curve, for example, the front direction, and it is possible to obtain an effect of facilitating acoustic adjustment. In addition, when the base part 230 is provided with sufficient strength to fix the diffusion column 220, a configuration without the top plate part 210 is also possible.
A plurality of diffusion columns 220 are provided in the columnar diffuser 20 and are columnar structures having different diameters. Each diffusion column 220 can diffract, diffuse and reflect sound waves having a frequency corresponding to the diameter of the column. As the material of the diffusion column 220, natural wood such as normal pine and cedar as with the top plate portion 210 and the base portion 230 can be used, but light wood such as balsa material can be used with lacquer or the like. It can also be used by increasing the strength by coloring or infiltrating the resin. Thereby, the whole columnar diffuser 20 can be reduced in weight, the damage to the floor | bed and articles | goods at the time of falling down can be suppressed, and handling can be made easy. Similarly, for the diffusion column 220, it is possible to select and use natural bamboos having different diameters.
The base portion 230 is a portion that supports the plurality of diffusion pillars 220 at the lower portion, and is configured such that a plurality of diffusion pillars 220 are inserted by making holes in the wood similarly to the top plate portion 210. Further, the shape of the base portion 230 is the same as that of the top plate portion 210 as shown in the plan view of FIG. In addition, in order to suppress the adverse effects of vibration from the floor and to suppress the rattling during installation, referring to the front view of FIG. 3 and the bottom view of FIG. Can do. At this time, a material such as butyl rubber or silicone gel for suppressing vibration may be bonded to a place in contact with the floor. Furthermore, the base part 230 can be provided with a weight provided with zircon sand or the like. Thereby, the stability at the time of installation of the columnar diffuser 20 can be increased.

Further, the arrangement of the plurality of diffusion columns 220 will be described in more detail.
Although the diffusion columns 220 are basically randomly arranged, a column with a small diameter is disposed in front of a sound wave that is mainly incident, and a column with a large diameter is disposed behind.
This is because it is acoustically unpreferable to place the thick diffusion column 220 on the near side when the column with the small diameter is arranged on the near side. This is because the diffusion pillar 220 having a large diameter diffuses at a lower frequency as described above, but the wavefront of the high frequency sound is not uniform in the direction of diffusion and the directivity becomes stronger.
Therefore, in the columnar diffuser 20 of the acoustic diffuser 1 according to the embodiment of the present invention, the thin diffusion column 220 is installed for the high range in front of the sound source so as to diffuse the high frequency sound wave.
As a result, the acoustic resistance (impedance) of the diffusion column 220 can be changed gently, and a large level of reflection can be avoided from occurring on the surface of the columnar diffuser 20.
In addition, regarding the random arrangement of each column of the diffusion pillars 220, it is possible to avoid coloration (coloration, change in timbre) of a specific frequency related to a regular arrangement.

Note that the shape of the diffusion column 220 is not a simple cylinder but may be a shape such as “entasis” in which the central portion is slightly inflated. Thereby, not only the horizontal direction of the room but also the vertical direction, the sound wave can be diffused, reflected and absorbed, so that a more natural sound field can be obtained. Moreover, the cross-sectional shape of the diffusion column 220 is not necessarily a circle, and an ellipse, a star shape, or the like can be used. Further, as described above, a structure having a knot like a bamboo may be used.
Further, when the diffusion columns 220 are arranged in rows (steps), an effect that the formation is simplified can be obtained.
In addition, the spacing between the diffusion columns 220 in the row is set randomly using random numbers so that the spacing varies with a random arrangement degree of about 5 to 50%.

In addition, when the rows of the diffusion columns 220 of each diameter are arranged in multiple stages, the interval between the columns is adjusted according to the parameter of the ratio at which the back can be seen on the projection plane perpendicular to the length direction of the diffusion columns 220.
As a default (standard setting), for example, when it is desired to increase the diffusion effect of the columnar structure, the projection area of the entire diffusion column 220 is 95% or more of the entire projection area in the direction perpendicular to the length direction of the column. It is good to be. That is, the placement adjustment is performed so that the back cannot be seen by the column group.
As a result, it is possible to reduce the influence of sound waves that have not been diffused by the diffusion column 220 and reflected from the back wall surface. Moreover, even when there is no wall surface behind, it can be used instead of a partition that does not adversely affect the sound field by making it impossible to look directly behind.

[Adjustment of bass absorption]
Here, the adjustment of the bass range using the cylindrical diffuser 10 will be described.
When the columnar diffuser 20 is arranged under the above-described arrangement condition, most of the mid-high range sound is reflected by the front row or middle row diffusion column 220, and mainly the low-frequency sound reaches the back of the back row and is transmitted. At this time, the low-frequency sound is out of phase. As a result, it is possible to obtain a good sound field that produces a sense of spaciousness of the room as compared with a conventional plate-shaped conventional acoustic panel.
Here, since it is necessary to form the columnar diffuser 20 so as to be placed beside the speaker in the room or the like, for example, a diffusion effect relating to a mid range and a high range of 1000 Hz or more can be obtained. The effect of absorbing and diffusing the following low-frequency sounds is not so great.
For this reason, in order to reduce low-frequency standing waves, flutter echoes, etc., particularly when speakers are installed in the corners of the room, in addition to the columnar diffuser 20, the cylindrical diffuser 10 can be used. It becomes possible to adjust the sound of the room effectively. In other words, the cylindrical diffuser 10 can solve the problem of low sound.
At this time, it is important to control the relationship between the frequency characteristic of the bass and the diffusion / sound absorption, the frequency band, the reflection direction, the reflection time structure, and the like according to the acoustic state of the room. In other words, it is necessary to control the rate at which sound of a specific frequency is diffused and the rate at which sound is absorbed.

Therefore, referring to FIG. 6, when the lower part of the upper cylinder 110 and the upper part of the lower cylinder 120 are combined and used integrally, the adjustment unit 130 is used to adjust the entire cylindrical diffuser 10. The height can be adjusted.
As a result, it is possible to adjust the strength of the low sound that is absorbed and diffused. Of course, it is also possible to provide the columnar diffuser 20 inside the cylindrical diffuser 10 after adjusting the height in this way. Usually, when the columnar diffuser 20 is provided inside the cylindrical diffuser 10, the diffuse radiation effect in the mid-high range can be weakened, which is effective when it is desired to suppress the reverberation of the room.
In addition, a resonance hole 140 can be formed in the upper cylinder 110 and / or the lower cylinder 120 of the cylindrical diffuser 10. As the diameter of the resonance hole 140, the frequency of “room noise” of the listening room used by the user can be used. That is, it is possible to absorb lower sounds by adjusting to the protruding points in the frequency band of the room. In addition, since the cylindrical diffuser 10 uses a soft material such as paper, the user can easily process it. More specifically, in the upper cylinder 110 or the lower cylinder 120, resonance holes corresponding to the frequencies of each bass sound are printed or perforated on the perforation line, and printed / processed by the perforation. It is possible to open a hole corresponding to the frequency. The holes are formed concentrically, and it is possible to obtain an optimum resonance frequency by opening the holes little by little from a high frequency of a small hole to a low frequency of a large hole. A plurality of the resonance holes 140 are provided, and the perforations corresponding to the respective frequencies can be separately prepared without forming concentric circles. Also, it is possible to make adjustments that act as sound inlets by opening a large number of resonance holes or providing a relatively large opening.
Furthermore, a sound absorbing material 150 having a high internal loss such as felt, glass wool, zircon sand, or the like can be separately packed in the upper column 110 or the lower column 120 of the cylindrical diffuser 10. Thereby, the low-pitched sound absorption effect can be further enhanced. The sound absorbing material 150 can be packed inside the upper column 110 or the lower column 120, and can also be packed when the upper column 110 and the lower column 120 are separated.
In this way, the mid-high range is diffused using the columnar diffuser 20, and the sound absorption and diffusion of the low range is controlled using the cylindrical diffuser 10, so that the room ringing frequency of the listening room used by the user is obtained. It is possible to obtain a wide range of diffusion effects from low to wide, while providing powerful sound-absorbing action that is targeted at the target.

[Example of arrangement of acoustic diffuser 1]
Next, an example in which the acoustic diffuser 1 is arranged in a room will be described with reference to FIG.
As described above, the acoustic diffuser 1 is installed in the most suitable place for adjusting the sound field such as the side of a speaker or the corner of a room without being separated into the cylindrical diffuser 10 and the columnar diffuser 20. Can be used.
In addition, the acoustic diffuser 1 can be used together with the columnar diffuser 20 by separating the cylindrical diffuser 10 as in the example of FIG.

The example of FIG. 7A is an example in which four acoustic diffusers 1 are used and arranged beside the speaker 30. FIG. 7A shows an example in which the cylindrical diffuser 10 and the columnar diffuser 20 of the acoustic diffuser 1 according to the embodiment of the present invention are used in combination. Here, the columnar diffusers 20 are arranged on the left and right sides of the speaker 30 when viewed from the listener L side, and the cylindrical diffuser 10 is disposed behind each columnar diffuser 20. Yes.
Conventionally, when a pair of speakers are placed on the short side of the room, the bass is enhanced and reflected, especially at the corners of the room, resulting in a muffled sound with too much bass, and the sound field is impaired. It often happens. In addition, for mid-high sounds, the reflected wave is reflected on the wall and reaches the listener L as the user as it is, so that it is difficult to obtain a sense of sound spreading beyond the width of the arrangement of the speakers 30.
On the other hand, the example of FIG. 7A diffuses the sound wave that spreads to the side of the speaker box of the speaker 30 as a spherical wave out of the frequencies of the loudspeaker 30 from, for example, a tweeter or a squawker. Can be made. Furthermore, for example, a low-frequency sound wave coming out of the bass reflex port of the speaker 30 or a sound “sucking” in the corner of the room can be absorbed and diffused by the cylindrical diffuser 10.
As a result, the reflected wave that reflects off the wall and reaches the user's ear can be broadened, flutter echoes, etc. can be reduced, the reverberation can be enhanced, and a sound field environment more favorable for the listener L can be obtained. is there. As a result, the sound reproduced from the original speaker 30 can be prevented from being “contaminated” by extra echoes in the room, for example, vocals can be clearly clarified, and the sound of each instrument can be heard clearly, The effect of being able to view with a more natural sound field feeling is obtained. Further, the low-pitched “fogging” can be adjusted by the arrangement of the cylindrical diffuser 10 and the resonance hole 140 or the sound absorbing material 150 according to preference.

The example of FIG. 7B is also an example in which four acoustic diffusers 1 are used. In FIG.7 (b), the example which isolate | separated and used the cylindrical diffuser 10 and the columnar diffuser 20 of the acoustic diffuser 1 which concerns on embodiment of this invention is shown. Here, an example is shown in which the columnar diffuser 20 is placed beside a speaker or the like, and the cylindrical diffuser 10 is disposed at the corner of the room.
For example, when the speaker 30 with the bass reflex port in the front is arranged at the corner of the room, the low-pitched sound is often lighter than the speaker with the bass reflex port on the back.
For this reason, as shown in FIG. 7B, by placing the cylindrical diffuser 10 in the corner of the room behind the listener L, it is possible to obtain a larger improvement effect in the low range, and the flutter echo in the low range. And standing waves can be reduced. Furthermore, by absorbing low sounds, it is possible to suppress wall noise and floor noise that resonate with the wall. As a result, it is possible to further enhance the presence of sound effects such as movies. In addition, the timbre of instruments such as bass and timpani that contain many bass sounds becomes clearer, making it possible to listen to lively sounds.

In addition to the example of FIG. 7B, it is possible to use only a plurality of cylindrical diffusers 10 at positions other than the back of the speaker. In this case, the cylindrical diffuser 10 is inexpensive as described above. Therefore, it is easy for the user to order and purchase separately.
Further, at least one acoustic diffuser 1 can be used. When two acoustic diffusers 1 are used, the acoustic diffuser 1 can be installed only on the left and right speakers 30 closer to the left and right walls of the room.
Further, the upper cylinder 110 or the lower cylinder 120 can be separated and used. That is, it is possible to separate the upper cylinder 110 and the lower cylinder 120 of the cylindrical diffuser 10 and separately arrange them at the corners or near the walls of the room. As a result, the upper column 110 or the lower column 120 can be used as furniture such as a chair and a stool and is not only obstructive, but also serves as a low-frequency diffusion / sound absorbing member to improve indoor sound. Can do.
Further, the acoustic diffuser 1 can be used not only in a stereo system as in the example of FIG. 7 but also in a system including a plurality of speakers such as a surround system.

[Comparison by Arrangement of Cylindrical Reflector 10 by Simulation]
Here, the result of having performed simulation about the sound improvement effect of the room by the arrangement of the acoustic diffuser 1 will be described.
Of the acoustic diffuser 1, the columnar diffuser 20 can be placed next to the speaker in the middle and high sound range to diffuse sound waves. According to the experimental results (not shown), it diffuses well regardless of the difference in the shape of Tallboy speakers, floor speakers, etc. and the driving method of horn speakers, electrostatic speakers, dynamic speakers, etc. I understood that.
In the case where the cylindrical diffuser 20 is arranged as shown in FIG. 7 (a), the bass reflex port shape and whether or not the rear diffuser is used for diffusion / absorption in the low frequency range. It was found that bass can be diffused and absorbed without being affected by the difference in shape.

Further, as shown in FIG. 7 (b), when the cylindrical reflector 10 is separated and placed in the corner of the room, a simulation is performed to specifically improve the room acoustics. investigated.
Below, the result of having simulated the diffused effect by the difference method using the numerical simulation at the time of separating and arrange | positioning the cylindrical reflector 10 which concerns on embodiment of this invention in the corner of a room is demonstrated. This simulation was performed by a two-dimensional difference method using “comfida” software manufactured by Nittobo Acoustic Engineering.
As the calculation space of the diffraction target that is the shape of the room, the calculation by the compact difference method was performed for a width of 7 m and a depth of 9 m.
The coordinates of one speaker 30 as a sound source are a position of 1.7 m from the left end and a depth of 1.5 m based on the upper left coordinates of the target space. A general Gaussian wave packet was used as a sound source (sound wave generation source) output from the speaker 30.

(Comparative Example 1)
First, with reference to FIG. 8A, the comparative example 1 which is a simulation result when nothing is arrange | positioned in the room is demonstrated.
Here, as described above, the sound pressure distribution in the 100 Hz band when only one speaker 30 is arranged in the square room of FIG. 8A is shown. In addition, the wall surface was comprised so that it might absorb some sound like normal wallpaper. The white numbers indicate the sound pressure (db).
As described above, when only the speaker 30 is arranged in the room, the peak of the sound pressure and the dip difference such as flutter echo appear large like a mottled pattern.

Example 1
Next, with reference to FIG. 8B, Example 1 which is a simulation result at the time of arrange | positioning the cylindrical diffuser 10 in the four corners of a room is demonstrated.
FIG. 8B shows a sound pressure distribution in a 100 Hz band when only one speaker 30 is arranged in a square room having the same size as FIG. 8A. And in FIG. 8B, the separated cylindrical diffuser 10 is arrange | positioned in the location 0.7m wide and 0.5m long from each corner of the room. As in FIG. 8A, the wall is configured to absorb some sound, and the white numbers indicate the sound pressure (db).
Comparing Example 1 in FIG. 8B and Comparative Example 1 in FIG. 8A, the distribution of the sound pressure becomes smoother and the peak of the sound pressure becomes larger when the cylinder is arranged in the corner as shown in FIG. 8B. It can be seen that there is little difference from a dip with a small sound pressure. Thereby, there are few low sounds which have a bad influence on a sound field like a flutter echo, and it has become a favorable sound field.
Therefore, even if the cylindrical diffuser 10 is arranged in the corner of the room, flutter echoes and the like for the low sound range generated in the room can be reduced, and a good sound field can be obtained.

  As described above, according to the acoustic diffuser 1 according to the embodiment of the present invention, the columnar diffuser 20 that forms a plurality of reflective surfaces in which the reflection direction / reflection time delay (phase) in the mid-high range is randomly reflected; By using the cylindrical diffuser 10 that absorbs and diffuses low frequencies, the acoustics of the room can be remarkably improved.

With the configuration described above, the following effects can be obtained.
First, the acoustic panel device of the prior art 1 has a problem in that the characteristics of the high sound, medium sound, and low sound range are determined from the material, shape, and dimensions. Therefore, in order to improve the sound of the room, it is not possible to improve the sound by dividing it into a high sound range and a middle and low sound range, and only sound absorption and reflection according to the frequency characteristics of the sound panel device are performed at the installed position. It was only. For this reason, in order to acquire the sound improvement effect, the effect was not enough.
On the other hand, the acoustic panel device according to the embodiment of the present invention can separate the columnar diffuser 20 corresponding to the mid-high range and the cylindrical diffuser 10 corresponding to the low range. Thereby, the arrangement | positioning location of the columnar diffuser 20 and the cylindrical diffuser 10 corresponding to a low sound range can be freely adjusted in the room, and the optimum sound field can be adjusted in accordance with the shape and acoustic characteristics of the room. it can. That is, it is possible to configure a diffuser that improves a wide sound field in a user's listening room having various acoustic characteristics.
Furthermore, it is possible to flexibly cope with a difference in sound field due to a difference in formation position of a speaker system having various characteristics, for example, a bass reflex port.

In addition, since the columnar diffuser 20 is formed in an arc shape or an arc shape, it can diffuse the mid-high range sound with a certain degree of directivity. Thereby, the arrangement | positioning according to the frequency characteristic and phase characteristics of a speaker etc. is attained.
Also, the cylindrical diffuser 10 can be arranged according to the shape of a bass reflex port such as a speaker or a woofer, and can effectively absorb and diffuse bass.

Further, in the conventional acoustic panel, when the user receives the acoustic panel and takes out the contents acoustic panel, the packing material is normally discarded. Even if the discarded packing material can be melted and recycled, it was a waste of resources.
On the other hand, in the acoustic diffuser 1 which concerns on embodiment of this invention, since the cylindrical diffuser 10 can be manufactured with cheap materials, such as paper, it can be used also as a packing material. Thereby, resources can be utilized effectively and the cost of the packaging material itself can be reduced. Further, when the cylindrical diffuser 10 is formed of paper or the like, it can be manufactured at a low cost and can be easily recycled.

In addition, in the acoustic diffuser 1 according to the embodiment of the present invention, the columnar diffuser 20 is formed for the mid-high range, and the low-frequency tubular diffuser 10 having a frequency band matched to this is used. be able to.
Thereby, it is possible to easily adjust the degree of diffusion and sound absorption in the low range and the mid-high range.

Moreover, since the columnar diffuser 20 is formed thin and compact, it is easier to arrange than the columnar diffuser that is embedded in the wall.
Furthermore, since the columnar diffuser 20 allows air to escape to the rear as compared with the plate-like acoustic panel, the air conditioning of the room is not disturbed, and it is possible to suppress an adverse audio effect due to the air conditioning.
Further, the columnar diffuser 20 does not get in the way of the interior of a room as compared with a simple plate-like acoustic panel.

<Structure of the cylindrical diffuser 10 when the adjusting unit 130 is not provided>
In addition, regarding the cylindrical diffuser 10, the structure without the adjustment part 130 is also possible.
Referring to FIG. 9, a sectional view taken along the diameter of the cylindrical diffuser 10 is shown. In this example, the diameter of the upper end of the lower cylinder 120 is slightly narrowed, and the upper cylinder 110 is inserted and coupled. Thereby, even when there is no adjustment part 130, the height of the cylindrical diffuser 10 can be adjusted using the upper cylinder 110 and the lower cylinder 120, and the sound-absorbing / diffusing bass can be adjusted.
In the example of FIG. 9, a circular material of the same material is attached to the upper end portion of the upper cylinder 110 and the lower end portion of the lower cylinder 120, and the seam 115 is used to sew using a thread. It is fixed. Thereby, the intensity | strength of the upper cylinder 110 and the lower cylinder 120 can be increased. Therefore, even when there is no adjustment part 130, it can have sufficient intensity | strength as a packaging material and can improve durability.

  It should be noted that the configuration and operation of the above-described embodiment are examples, and it is needless to say that the configuration and operation can be appropriately changed and executed without departing from the gist of the present invention.

DESCRIPTION OF SYMBOLS 1 Acoustic diffuser 10 Cylindrical diffuser 20 Columnar diffuser 30 Speaker 110 Upper cylinder 115 Seam 120 Lower cylinder 130 Adjustment part 140 Resonance hole 150 Sound absorption material 210 Top plate part 220 Diffusion pillar 230 Base part L Listener

Claims (7)

A columnar diffuser for mid-high range with a plurality of columns with different diameters,
A cylindrical diffuser for a low frequency range,
An acoustic diffuser, wherein the columnar diffuser is configured to be retractable or separable inside the cylindrical diffuser. The acoustic diffuser according to claim 1, wherein the cylindrical diffuser is configured to be extendable and configured to adjust a degree of absorption / diffusion of bass by changing a height. The acoustic diffuser according to claim 1, wherein the cylindrical diffuser includes a resonance hole and / or an acoustic introduction port. The acoustic diffuser according to any one of claims 1 to 3, wherein the cylindrical diffuser is configured to be able to incorporate a sound absorbing material. The acoustic diffuser according to claim 1, wherein the cylindrical diffuser is used as a packing material. The acoustic diffuser according to any one of claims 1 to 5, wherein the columnar diffuser includes a plurality of cylinders having different diameters arranged in a curved line. A columnar diffuser in which a plurality of columns having different diameters and a cylindrical cylindrical diffuser are combined and / or separated and arranged in a room,
Diffusing the mid-high range by the columnar diffuser
A sound diffusion method characterized by diffusing / absorbing the low frequency range by the cylindrical diffuser.

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