JP2002300683A - Multichannel microphone - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize a stereo microphone which can be installed in close contact with the floor, wall, or the like so that it may not be conspicuous on the TV screen and which has a flat frequency characteristic and has a higher sensitivity. SOLUTION: Two microphone capsules 2 and 4 are disposed in a single housing 1 to construct a boundary-type stereo microphone.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multi-channel microphone capable of collecting sound of two or more channels such as a stereo, and all components are housed in a single housing. It relates to a multi-channel microphone.

[0002]

2. Description of the Related Art The conventional stereo microphone system is described in several points from "Microphone / Speaker Discussion" by Shigeyoshi Tanaka, published in March 1995 by Kenrokukan Publishing Co., Ltd. 1) XY method SM589 (manufactured by NEUMANN) 2) MS method MK4 / MK8 (manufactured by Schoeps) 3) AB method MK2S (manufactured by Schoeps)

In the XY method 1), two unidirectional microphones are arranged so as to intersect with each other at an angle of 90 ° to 120 °, and a difference in sound level incident on the left and right microphones is obtained. It produces a stereo effect. In the MS method 2), microphones having unidirectionality and bidirectionality are arranged coaxially, and the outputs of the two microphones are added and subtracted to obtain the outputs of the left and right stereo channels. As in the XY method 1), the stereo effect is produced by the level difference. 3)
The AB method is a method in which the microphones are spaced apart to some extent to achieve a stereo effect due to a time difference, and is called a so-called pair microphone method.

[0004] All of these stereo microphones are used by being installed on a microphone stand, a hanging bracket, or the like. For example, even if an attempt is made to use the microphone hidden behind props in a stage performance or drama recording, the size of the microphone itself is large. At present, there are no stereo microphones that are small and can be installed inconspicuously on TV screens, as it is inappropriate to do so, and the frequency response is disturbed by the sound reflected from the surrounding hard wall. Was.

[0005] Conventionally, there has been no boundary type stereo microphone that can be arranged close to a floor or a wall. The reason is that the structure and size of the microphone capsule incorporated in a single housing hindered, and it was difficult to incorporate a plurality of microphone capsules suitable for stereo sound collection in a single housing.

[0006]

As described above, conventional stereo microphones are installed on a microphone stand, a hanging bracket, or the like, and are therefore often used on a television screen. Therefore, for example, it is not suitable to be installed in a prop set of a drama, to be installed inconspicuously in front of a stage stage, or to be installed near an instrument.

Further, when a conventional small stereo microphone is installed near a wall or a floor, reflections from the floor or the wall cause irregularities in frequency characteristics, which has been a problem in practical use. Also, when recording a program, stereo microphones are often placed away from the sound source,
There has also been a problem that sufficient sensitivity cannot be obtained.

Further, the conventional microphone capsule has a cylindrical shape, and even if it is used to form a boundary type stereo microphone, it is difficult to incorporate it into a small single housing due to its external shape and size. .

SUMMARY OF THE INVENTION An object of the present invention is to provide a multi-channel microphone which eliminates the above-mentioned various problems, can collect sound of two or more channels such as a stereo, and has all components contained in a single housing. Is to do.

[0010]

In order to achieve the above object, a multi-channel microphone according to the present invention is a boundary-type multi-channel microphone, wherein a plurality of microphone capsules are arranged in a single housing. It is assumed that.

Further, the multi-channel microphone according to the present invention is characterized in that two unidirectional microphone capsules are arranged so as to cross each other and be stacked in the single casing.

Further, the multi-channel microphone of the present invention is characterized in that microphone capsules of unidirectional and bidirectional are coaxially stacked and arranged in the single casing.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below based on embodiments of the present invention with reference to the accompanying drawings. The present invention is a boundary-type multi-channel microphone.Here, the boundary-type microphone is a microphone designed so that a diaphragm or a sound wave introduction hole is as close as possible to a floor or a wall where the microphone is arranged. is there. In general, when a microphone is installed near a wall or floor, the reflected sound from the floor or wall causes irregularities in the frequency characteristics. It has the advantage of not standing.

Further, according to the boundary type microphone, the direct sound and the sound reflected from the floor or the wall drive the diaphragm in the same phase, so that the diaphragm receives a sound pressure twice that of a normal microphone. It is possible to increase the sensitivity by a factor of about 2 and thus achieve a high S / N.

FIGS. 1A and 1B are views of an embodiment of the multi-channel microphone of the present invention, as seen through the inside from the top and the front, respectively. FIG.
(A), (b), 1 is a housing, 2 is a sound wave introduction hole 3
Is a second thin microphone capsule having a sound wave introduction hole 5, and 6 is a microphone output cable.

In this embodiment, in the section of the prior art, 1) X
The stereo microphone described as the Y system is realized as a boundary type stereo microphone. As can be seen from the positions of the sound wave introduction holes 3 and 5 of the first and second thin microphone capsules 2 and 4 in FIGS. 1 (a) and 1 (b), they are arranged orthogonally to each other in the housing 1. Have been.

The size of each of the thin microphone capsules 2 and 4 is, for example, 11.4 mm (width) × 1.
It is 5 mm (depth) x 4.8 mm (height), and because of such a low height, the height is only 9.6 mm even when stacked in two stages. The housing 1 of a hemispherical stereo microphone in which these thin microphone capsules 2 and 4 are stacked and arranged inside has, for example, an outer diameter of about 2 mm.
Taking advantage of the small size, the height is about 16 mm at 3 mm, so that the microphone can be installed in a prop set such as a drama so that the microphone body is not visible, or can be installed without being noticeable on the front of the stage.

The sensitivity of the capsule of the stereo microphone according to the present embodiment alone and the equivalent noise level in terms of input are -34 dB (V / Pa) and 16 dB (A characteristic), respectively.
(All measured values), but the sensitivity was further increased by 6 dB due to the boundary effect, and the sensitivity was -28 dB (V / P
a), an unprecedented high sensitivity can be achieved.

Examples of the thin microphone capsules 2 and 4 used in the present embodiment include, for example, a patent application published by the present applicant (JP-A-5-260580).
No.) can be used. 2A and 2B are a perspective view and a cross-sectional view, respectively, of the microphone capsule described in this publication.

This microphone capsule is shown in FIG.
As shown in (a) and (b), in order to make the directional axis of the microphone substantially parallel to the diaphragm 7 and to make the configuration of the capsule thin with respect to a plane parallel to the directional axis, covers are provided before and after the diaphragm 7. 8 and 9 are attached. in this way,
By making the shape of the microphone capsule thinner with respect to a plane parallel to the directional axis, it becomes possible to arrange the directional axes closer to each other in a microphone that combines the outputs of a plurality of microphone capsules. Of the microphone, the deterioration of the synthesis characteristics of the microphone due to the inconsistency can be reduced. In FIGS. 2A and 2B, reference numeral 1 is used.
The portions indicated by 0 and 11 are spacers and back electrodes, respectively, and the portions indicated by reference numerals 12 and 13 are sound wave introduction holes (one acoustic terminal) to the front surface of the diaphragm and sound waves to the rear surface of the diaphragm, respectively. An introduction hole (the other acoustic terminal).

As described above, the microphone capsule described in Japanese Patent Laid-Open Publication No. Hei 5-260580 is thinner with respect to a plane parallel to the directional axis. It is particularly convenient to construct the multi-channel microphone of the present invention in which are stacked. However, in configuring the multi-channel microphone of the present invention, it goes without saying that any microphone capsule other than the microphone capsule described in Japanese Patent Laid-Open Publication No. 5-260580 can be used.

In the above description, the multi-channel microphone of the present invention is replaced with the XY of 1) described in the section of the prior art.
However, the present invention is not limited to this, and the 2) MS described in the section of the prior art is also used.
The system can be configured based on the system or the AB system of 3), or based on a stereo microphone system not described in this specification.

The microphone according to one embodiment of the present invention is a stereo microphone in which two microphone capsules are stacked and arranged in a single housing.
In the present invention, a plurality of microphone capsules may be arranged in a single housing to form a multi-channel microphone.

[0024]

According to the present invention, a stereo microphone (generally, a multi-channel microphone) that can be installed closely on a floor or a wall so as to be inconspicuous on a television screen, has a flat frequency characteristic, and has high sensitivity. Therefore, it is possible to increase the effect on program production by using the realized stereo microphone.

[Brief description of the drawings]

FIG. 1 is a perspective view of an embodiment of a multi-channel microphone of the present invention, as seen through the inside from the top and front.

FIG. 2 is a perspective view and a cross-sectional view of a microphone capsule described in a patent publication.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Housing 2 1st thin microphone capsule 3,5 Sound introduction hole 4 2nd thin microphone capsule 6 Microphone output cable 7 Vibration membrane 8,9 Cover 10 Spacer 11 Back electrode 12 Sound introduction hole to the front of vibration membrane (one side) 13 Sound introduction hole to the rear surface of the diaphragm (the other acoustic terminal)

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Masakazu Iwaki 1-10-11 Kinuta, Setagaya-ku, Tokyo Japan Broadcasting Corporation Broadcasting Research Institute F-term (reference) 5D017 BC15

Claims (3)

[Claims] 1. A multichannel microphone of a boundary type, wherein a plurality of microphone capsules are arranged in a single housing. 2. The multi-channel microphone according to claim 1, wherein two unidirectional microphone capsules are arranged so as to intersect each other and are stacked in said single housing. 3. The multi-channel microphone according to claim 1, wherein unidirectional and bidirectional microphone capsules are stacked coaxially in the single casing.