JPH0635488A - Board and foot for a/v equipment or musical instrument - Google Patents

Abstract

PURPOSE:To obtain the pedestal for A/V equipment or musical instrument which generates sound quality faithful to a source sound over a wide frequency range from a low-frequency range to a high-frequency range without being limited by the installation place. CONSTITUTION:A sandwich structure is formed by using plywood 2 as a center material and laminating an iron plate 4 on its reverse surface and a carpet 3 on the top surface, and a through hole 6 is formed penetrating the center part to obtain the board 1 for A/V equipment or musical instrument. Wooden feet 7 are fitted to the reverse surface of the board 1. The wooden feet 7 are formed in a rectangular parallelepiped or cubic shape having a top and a reverse square surface, the grain of the wood on the top and reverse surface runs in parallel to the ridges, and the top or reverse surface is beveled. Consequently, fine harmonic vibration which is erased by a conventional pedestal can be reproduced and noise vibration which interferes with musical vibration can be eliminated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a so-called A / V (audio / visual) device such as an audio device, a television, a video, or a pedestal for mounting a musical instrument, and more specifically, to an A / V device. Equipment or instrument board,
And a foot particularly suitable as a leg of the board.

[0002]

2. Description of the Related Art Since A / V equipment has a great influence on the sound quality even if it has a minute level of vibration, countermeasures against vibration are still an important issue. The vibrations that should be considered in A / V equipment include the original music vibration itself, the resonance of the equipment caused by the music vibration, the vibration of the equipment due to a machine such as a motor, and the secondary vibration of the equipment, that is, from the pedestal. Vibrations that are transmitted to the equipment (including vibrations that are transmitted from the equipment to the pedestal and then returned to the equipment, and vibrations from outside that come through the floor, etc.), etc. As harmful vibration, measures have been taken to suppress it as much as possible. For that purpose, as a pedestal for mounting the A / V device, (a) a material having a high vibration damping capability, or (b) a material having a high rigidity and a large mass and a high braking force against vibration is preferable. Came.

Materials used at present are roughly classified into soft members such as urethane rubber and sorbosein (trade name), or hard members such as gray cast iron. Since it has both characteristics, it is widely used as an audio pedestal (board or insulator) at present.

[0004]

However, even if these materials are used, it has been difficult to bring out a sound quality faithful to the original sound over a wide frequency band from the low tone range to the high tone range. The first reason is that a part of the music vibration is removed by the excessive vibration suppressing function of the pedestal. In other words, among the original music vibrations, the weak harmonic vibrations that greatly affect the sound quality are absorbed and cannot be reproduced.

The second reason is that in addition to the fact that the resonance of the equipment cannot be completely suppressed, the vibration peculiar to the material of the pedestal is transmitted to the equipment. It is because the vibration damping capacity of these materials is not as large in the entire frequency band, and there is a band where the damping capacity is not sufficient, especially the resonance of the equipment in that band cannot be suppressed, and the band where the damping capacity is not sufficient. There are natural frequencies of these materials, especially the vibration coming through the floor cannot be effectively suppressed,
This is because some vibrations are reflected on the surface of the pedestal. These vibrations interfere with the original music vibrations as noise, resulting in muddy or distorted sound.

For example, when these materials are used as a pedestal for a speaker, when a soft material such as urethane rubber is used, not only a weak overtone component is reproduced in the entire band but also some fundamental sounds are attenuated. However, the sound quality is deteriorated, and the sound quality does not have a sense of speed, such as a muffled focus even in the low frequency range. On the other hand, when a hard member such as gray cast iron is used, although there is no extreme attenuation as seen with soft materials, the weak overtone component is not reproduced in the entire band, especially in the middle and low range, which is unchanged.
In addition, it is susceptible to secondary vibrations from the floor, resulting in a monotonous sound lacking in energy, which is peculiar to hard members.

As described above, there has been a limit to the conventional measures against vibration, which is focused only on suppressing all vibrations other than music vibrations. That is, even if a material having an extremely high vibration damping ability is used as a board for A / V equipment, vibration peculiar to the material of the pedestal is transmitted to the A / V equipment and the sound quality is not affected. Not only is it inevitable, but some of the overtone components, which are extremely important for sound quality, cannot be reproduced.

The present inventor should change the idea from the conventional measures against vibrations, and should avoid those having extremely large vibration damping ability in order to reproduce the weak overtone component of music vibration. , And the vibrations peculiar to the material of the pedestal, etc. are attenuated inside the pedestal and escaped to the floor so that the vibrations from the equipment are not transmitted to the equipment, and the vibration from the floor is not transmitted to the equipment. From the above, the material was selected through trial and error, and the shape and the like were devised to obtain a board and foot suitable for A / V equipment.

[0009]

A board for A / V equipment according to the present invention has a sandwich structure in which a plywood is used as a central material, an iron plate is laminated on the lower surface, and a carpet layer is laminated on the upper surface. It is characterized by having an opening penetrating into Here, the plywood means two or more single plates that are laminated so that the wood grain is at a right angle. For example, it is possible to use a commercially available veneer veneer having a thickness of about 0.3 to 5 mm, which is laminated at right angles on the grain and adhered with an adhesive.
The plywood preferably has a large mass in order to have a vibration damping ability to some extent, and preferably has a thickness of 10 mm or more in which five or more layers are laminated.

The iron plate to be laminated on the lower surface of the plywood plate may be an ordinary mild steel plate or a cast iron plate having a high vibration damping ability, mainly for the purpose of compensating the rigidity and the lack of mass of the plywood plate. The carpet (carpet) layer laminated on the upper surface of the plywood does not directly transmit mechanical vibration or music vibration generated by the A / V equipment to the plywood, or conversely, does not transmit vibration of the plywood directly to the A / V equipment. Any material such as natural fiber or synthetic fiber can be used, but it has a two-layer structure with a slightly hard base and a fluffy surface, and a thickness of 2-5 m.
m thin carpet can be preferably used.

Although the A / V equipment board according to the present invention can be used alone, it is preferable to use the foot described below on the lower surface.

The wooden foot for A / V equipment according to the present invention is a rectangular or cubical wooden having square upper and lower surfaces, and the grain of the upper and lower surfaces runs parallel to the ridge line, and either the upper surface or the lower surface. Is chamfered. This foot is particularly suitable as a leg of the above-mentioned A / V equipment board according to the present invention, but a corresponding effect can be obtained even when the A / V equipment is directly mounted. As a result of making and listening to various foot materials, it was found that cherry wood was the most effective.

The board and foot described above are
It can be used not only as a / V device but also as a pedestal for musical instruments.

[0014]

When the A / V device is mounted on the board according to the present invention, the sound quality faithful to the original sound can be obtained over a wide frequency band from the low range to the high range. It is thought that this is because even weak harmonic overtones can be reproduced, and the vibration peculiar to the material of the board does not interfere with the music vibration. When placed on the board according to the present invention, such weak overtone components can be reproduced in such a way that the plywood peculiar laminated structure, which is the main constituent material of the board, and the specific frequency with its vibration damping ability It is considered that the contribution is not biased and is not extremely large.

Further, in the board according to the present invention, the vibration peculiar to the material does not interfere with the music vibration because the external vibration, the mechanical vibration generated by the A / V equipment, the music vibration, etc. It is considered that the vibration was not retransmitted to the equipment placed on the top because the part was attenuated and disappeared in the board when it was transmitted, and the rest was dissipated downward (floor). . The reason is not always clear, but the plywood's peculiar laminated structure, which is the main constituent material of the board, and the sandwich structure of the plywood and the other two layers, may have an organizing effect on the transmission of vibration components. It is presumed that there is. When placed on plywood only, interference may occur because the vibration is transmitted to the top as well.
The high and mid frequencies are bright on the surface and the level is raised (more noticeable).

Now, in the board according to the present invention,
An iron plate was laminated on the lower surface and a carpet layer was laminated on the upper surface. The reason for laminating the iron plate on the lower surface is that the plywood alone lacks rigidity and mass, and has a difficulty in braking force against vibration. on the other hand,
The reason why the carpet layer is laminated on the upper surface is to avoid direct contact between the A / V device and the plywood. If the plywood and A / V equipment are in direct contact without this carpet layer,
On the contrary, the integration of the board and A / V equipment is hindered
The vibration of the V equipment is directly reflected on the plywood surface, which interferes with the original music vibration and deteriorates the sound quality.

In addition, since the board according to the present invention has an opening vertically penetrating at the center thereof, noise vibration interfering with music vibration can be more effectively eliminated. It is considered that this is because the vibrations transmitted in the plywood tend to be concentrated in the central portion thereof, and the vibrations reaching the openings having different phases interfere with each other and are attenuated.

By the way, it has been thought that the A / V device can reproduce high sound quality for the first time by preparing a special place such as a listening room. However, the A / V device is mounted on the board according to the present invention. When you do, the music vibration from the speaker becomes pure vibration without distortion, so it will not be affected by the room such as the difference between the left and right conditions of the installation location and the size of the room, and it will also be covered with a plate, tatami mat, rug, Alternatively, almost the same effect is observed under various conditions such as on a rack.

The wooden foot for A / V equipment according to the present invention is used by arranging it under the board so that the grain directions running parallel to the ridgelines of the upper and lower surfaces thereof are aligned front and back. When the grain direction is used in this way, the sound quality is further improved, probably because the vibration of the board is successfully transmitted to the floor.
Also, it is more effective to use the chamfered side down, but this is probably because the vibration coming from the floor side is less likely to be transmitted.

Even when this foot is placed directly under the A / V equipment, the vibration of the equipment escapes to the floor via the foot.
Vibrations coming from the floor are less likely to be transmitted to the top, so a corresponding effect is recognized. At this time, if the wood grains are arranged in the front-rear direction, the sound has a sense of depth, and if the wood grains are arranged in the left-right direction, the sound is spread by the left and right sounds.

The above description is for using the board or foot according to the present invention as a pedestal for A / V equipment, but for a musical instrument such as a piano or cello that has a portion that abuts on the floor. Similar effects can be obtained when used as a pedestal. In the case of a cello having a thin tip, it is possible to form a recess on the upper surface of the board or foot and place the tip there.

[0022]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A board and a foot according to the present invention will be described in more detail below with reference to FIGS. here,
1 is a perspective view of a board to which a foot is attached, FIG. 2 is a plan view thereof, FIG. 3 is a sectional view taken along the line II of FIG. 2, and FIG. 4 is a perspective view of the foot.

The board 1 according to the present invention is formed by laminating a carpet layer 3 and an iron plate 4 on the upper and lower surfaces of a plywood 2 formed by laminating veneer single plates. It is suitable that the carpet layer 3 is adhered to the upper surface of the plywood 2 with an adhesive, the iron plate 4 is adhered to the lower surface of the plywood 2 with an adhesive, and several points are fixed with screws 5. An opening 6 is provided in the central portion of the board 2 so as to vertically penetrate therethrough. As a result of many experiments, it has been found that the shape of the board 2 can reproduce the sound most faithful to the original sound when the ratio of the length / width is 1.07: 1.

The foot 7 according to the present invention has an overall shape of a rectangular parallelepiped or a cube, and the wood grain 8 of the upper surface 7a and the lower surface 7b run parallel to the ridge line 9 and the corner of either one of the upper surface 7a and the lower surface 7b. 10 is chamfered. When in use,
As shown in FIG. 5, the chamfered side is preferably the lower surface, and the wood grain 8 is set so as to face the front-back direction (the viewer's position is the front).

Now, according to the present invention, the following boards and feet were prepared. The size of the board is 452mm x 4
Thickness of 85 mm and laminated with 7 sheets of veneer veneer
mm commercially available plywood, 3 mm thick commercial carpet, and 2.3 mm thick mild steel plate with a diameter of 1 at the center of each.
A 6 mm hole was punched and these were laminated. The plywood and the carpet were adhered only with the adhesive, the plywood and the mild steel plate were adhered with the adhesive, and 12 places shown in FIG. 2 were screwed.

The foot is cut out from the cherry tree material so that the grain of wood runs parallel to the ridgelines of the upper and lower surfaces, and it is 20 mm × 20 mm.
It was molded into a size of × 16 mm (vertical direction), and the corner of one surface was chamfered as shown in FIG. Four boards with the same foot were prepared, the non-chamfered side was faced to the bottom surface of the board, the grain directions were aligned and bonded to complete the board.

In the music studio, 300
A case where a loudspeaker (mm (W) x 370 mm (D) x 1040 mm (H)) (weight 32 Kg, allowable input 100-600 W) is placed and played on the above board, and directly placed on the floor. By comparison, the former was able to reproduce music that was faithful to the original sound and had no turbidity or distortion over a wide frequency band from the low range to the high range.

Next, a DAT (digital audio tape) deck (size 435 mm (W) x 370 mm (D) x 1)
33 mm (H), weight 16 kg) was placed on the board, a musical performance was recorded, and this was reproduced to examine the envelope waveform, and the waveform shown in FIG. 5 was obtained. on the other hand,
Place the same DAT directly on the floor, record the music performance,
When I played this and examined its envelope waveform,
A waveform as shown in FIG. 6 was obtained. As is well known, in DAT, the best envelope waveform is obtained when each head correctly tracks the track pattern on the tape. Specifically, the good sound condition in DAT is
Although the level L of the envelope waveform is large and the waveform is flat (the flatness from the rising S side to the falling T side is good and the waveform is rectangular), the waveform itself is clear and powerful. When it was used, all the conditions were satisfied as apparent from FIG. 5, while when it was not used, the waveform lacked flatness as seen in FIG.

[0029]

As described above, when an A / V device is placed on the board or foot according to the present invention, even a fine harmonic vibration can be reproduced, and it interferes with music vibration. It effectively eliminates noise vibration and can bring out sound quality that is faithful to the original sound over a wide frequency band from the low range to the high range. Moreover, it is possible to reproduce high sound quality without preparing a special room such as a listening room. The same effect can be obtained when the board or foot according to the present invention is used as a pedestal of a musical instrument such as a piano or a cello that has a portion that comes into contact with a floor material.

[Brief description of drawings]

FIG. 1 is a perspective view of a board to which a foot is attached.

FIG. 2 is a plan view of a board with feet attached.

3 is a cross-sectional view taken along the line I-I of FIG.

FIG. 4 is a perspective view of a foot.

FIG. 5 is an envelope waveform when the board of this embodiment is used as a DAT pedestal.

FIG. 6 is an envelope waveform when DAT is placed directly on the floor.

[Explanation of symbols]

 1 board 2 plywood 3 carpet 4 steel plate 5 screw 6 opening 7 foot 7a foot upper surface 7b foot lower surface 8 wood grain 9 upper or lower foot ridge 10 corner chamfered

Claims (6)

[Claims] 1. A board for A / V equipment, which has a sandwich structure in which a plywood is used as a central material, an iron plate is laminated on a lower surface of the plywood, and a carpet layer is laminated on an upper surface thereof, and an opening vertically passing through the central portion is formed. . 2. A rectangular parallelepiped or a cube having upper and lower surfaces of a square, wherein the grain of the upper and lower surfaces run parallel to the ridge, and the corners of either the upper surface or the lower surface are chamfered. / Wooden foot for V equipment. 3. A board for A / V equipment according to claim 1, wherein the wooden foot for A / V equipment according to claim 2 is arranged on the lower surface with the grain directions aligned. 4. A musical instrument board having a sandwich structure in which a plywood is used as a central material, an iron plate is laminated on a lower surface of the plywood, and a carpet layer is laminated on an upper surface of the plywood. 5. A musical instrument, which is a rectangular parallelepiped or a cube having upper and lower surfaces of a square, wherein wood grains of upper and lower surfaces run parallel to a ridge line, and a corner of one of the upper surface and the lower surface is chamfered. For foot. 6. The wooden foot for musical instrument according to claim 5,
The musical instrument board according to claim 5, wherein the grain surfaces are arranged in the same direction so as to be aligned with each other.