JP2006287347A - Attenuator for condenser microphone and condenser microphone - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an attenuator for a condenser microphone the attenuation capacitor of which can easily be replaced that can inexpensively be manufactured with less number of components without almost no effect on the outward form of a microphone. <P>SOLUTION: The attenuator 30A for the condenser microphone that is removably interposed between a condenser microphone unit 10 comprising a diaphragm assembly 12 contained in a cartridge case 11, the diaphragm assembly 12 comprising a diaphragm 12a and a fixed pole 12b opposed to each other via a spacer, and a microphone main body 20 comprising a power module section including an impedance converter, a sound output circuit and a polarized power supply circuit contained in a microphone housing 21, includes the attenuation capacitor connected in parallel with a capacitor comprising the diaphragm 12a and the fixed pole 12b, is provided with a circuit board 300 clamped between the condenser microphone unit 10 and the microphone main body 20, and the attenuation capacitor 305 is mounted on the circuit board 300. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a condenser microphone in which a condenser microphone unit can be replaced. More specifically, the present invention relates to an attenuator for adding a predetermined attenuation amount to a condenser microphone unit.

  As the condenser microphone, there is a condenser microphone called a stick type that can exchange condenser microphone units having different directivities. In this type of condenser microphone, cardioid, hypercardioid, omnidirectional, and bidirectional directivity condenser microphone units are prepared, the unit is selected according to the purpose of sound collection, and the microphone body with a built-in power module Used in combination with.

  Usually, in this type of condenser microphone, the condenser microphone unit does not include an impedance converter (in many cases, FET (field effect transistor)), and the impedance converter is provided on the power module side of the microphone body.

  In a condenser microphone, when a loud sound is input, distortion occurs in an audio signal in an audio output circuit. In order to prevent this, a condenser (attenuating condenser) is connected in parallel with the condenser microphone unit to attenuate the audio signal input to the impedance converter.

  This attenuator for attenuating the audio signal is referred to as a PAD (pad), and an attenuator having an appropriate amount of attenuation is used particularly when a microphone is brought close to a musical instrument or the like. An example of a stick-type condenser microphone using an attenuator will be described with reference to FIGS. 4 is an exploded view showing a state before assembly, and FIG. 5 is an assembly view.

  In this condenser microphone, the condenser microphone unit 10 and the microphone main body 20 are detachable, and an attenuator 30 is interposed between them. The condenser microphone unit 10 used in this example is a unidirectional unit, and has a cylindrical cartridge case 11 having a front acoustic terminal opening 11a on the front side and a rear acoustic terminal opening 11b on the side surface. I have. The cartridge case 11 is made of a metal material such as aluminum or brass alloy.

  In the cartridge case 11, a diaphragm assembly 12 in which a diaphragm 12a and a fixed pole 12b are arranged to face each other via a spacer (not shown) is arranged on the opening 11a side of the front acoustic terminal. A connecting ring 15 having a male screw 15a is integrally attached to the rear end side of the cartridge case 11, and the opening on the rear end side of the cartridge case 11 and the inside of the connecting ring 15 are sealed with insulating materials 16a and 16b. The

  A lead electrode rod 13 that is electrically connected to the fixed pole 12b is provided through the central portion of the insulating materials 16a and 16b. In this example, the extraction electrode rod 13 includes a retractable contact pin 13a biased by a coil spring 13b.

  The microphone body 20 includes a cylindrical microphone casing 21 made of a metal material such as aluminum or brass alloy. On one end side (the upper end side in FIG. 4) of the microphone casing 21, a female screw 21a that is screwed with the male screw 15a of the connecting ring 15 is formed, and a lead terminal 25 is provided below the female screw 21a. The formed insulating seat 22 is fitted and fixed.

  An output connector 23 is attached to the lower end side of the microphone casing 21. The output connector 23 is a connector defined in EIAJ RC-5236 “Latch lock type circular connector for audio equipment”, and includes three pins: a ground terminal pin, a signal hot terminal pin, and a signal cold terminal pin. . For convenience of drawing, only two of the terminal pins 23a and 23b are shown in FIG. The output connector 23 is connected to a phantom power source (not shown).

  In the microphone casing 21, the circuit board 24 is accommodated while being supported between the insulating seat 22 and the output connector 23. Although not shown, the circuit board 24 is mounted with a power module unit including an impedance converter (FET), an audio output circuit, and a polarized power supply circuit. The microphone body 20 itself may be referred to as a power module unit.

  The attenuator 30 includes a cylindrical housing 31 made of a metal material such as aluminum or brass alloy. 4 is formed on the upper end side of the housing 31 in FIG. 4, and the female screw 21 a of the microphone casing 21 is formed on the lower end side of the housing 31. A connecting ring 34 having a male thread 34a that is screwed together is integrally formed. The inside of the connection ring 34 is sealed with an insulating material 36.

  An insertion board 32 is housed in the housing 31, and a damping capacitor (not shown) connected in parallel with the capacitor formed by the diaphragm 12 a and the fixed pole 12 b is mounted on the insertion board 32.

  An electrode pad 35 that comes into contact with the contact pin 13a of the extraction electrode rod 13 is provided at the central portion of the insertion substrate 32, and the electrode pad 35 is electrically connected to the central portion of the insulating material 36 via a coil spring 33b. The contact pin 33a connected to is provided so as to appear and retract. The contact pin 33a contacts the lead terminal 25 on the microphone casing 21 side.

  In this stick type condenser microphone, when the attenuator 30 is not required, the coupling ring 15 is screwed into the female screw 21a of the microphone casing 21, and the condenser microphone unit 10 is directly connected to the microphone body 20. Connecting.

  Separately from this, for example, when collecting a microphone close to a musical instrument or the like, in order to prevent distortion of the audio signal due to the loud sound, as shown in FIG. An attenuator 30 is interposed between the main body 20 and an attenuating capacitor (not shown) in the attenuator 30 is connected in parallel to the capacitor formed by the diaphragm 12a and the fixed pole 12b.

  The amount of attenuation depends on the capacitance of the attenuating capacitor. Therefore, when a large amount of attenuation is required, the attenuator 30 having an attenuating capacitor having a large capacitance is selected.

  However, in the above-described conventional example, since the attenuator 30 is interposed between the condenser microphone unit 10 and the microphone body 20, threading is required at both ends of the housing 31 of the attenuator 30. Further, since the attenuator 30 requires the relay pin 33a for connecting the condenser microphone unit 10 and the microphone main body 20, an increase in cost is inevitable.

  Furthermore, when the attenuator 30 is used, the attenuator 30 constitutes a part of the outer shape of the microphone. Therefore, from the viewpoint of design, it is necessary to determine the outer shape, color tone, and the like so as to have uniformity with the outer shape of the applied microphone.

  In addition, since the attenuating capacitor is mounted on the insertion board 32 in the housing 31, there is a problem that it is difficult to replace the attenuating capacitor and it is not possible to quickly cope with a specification change or the like.

  Therefore, an object of the present invention is to provide an attenuator that can be manufactured at a low cost with a small number of components, hardly affects the external shape of the microphone, and can easily replace the attenuation capacitor. is there.

  In order to solve the above problem, the invention according to claim 1 is a condenser microphone unit in which a diaphragm assembly in which a diaphragm and a fixed pole are arranged to face each other via a spacer is housed in a cartridge case; A power module unit including an impedance converter, an audio output circuit, and a polarized power supply circuit is detachably interposed between the microphone main body housed in the microphone case, and includes the diaphragm and the fixed pole. An attenuator for a condenser microphone having an attenuating capacitor connected in parallel to a condenser that includes a circuit board sandwiched between the condenser microphone unit and the microphone body, wherein the attenuating capacitor is provided on the circuit board. Is implemented.

  According to a preferred aspect of the present invention, as described in claim 2, the circuit board is a double-sided circuit board, and one surface of the circuit board is connected to an extraction electrode rod on the condenser microphone unit side. A first electrode terminal and a first ground terminal which is annularly arranged around the one surface and connected to the cartridge case are formed, and the first surface is formed on the other surface of the circuit board. A second electrode terminal that is electrically connected to the electrode terminal and through the through-hole wiring and is connected to the lead terminal on the power module unit side, and is annularly disposed around the other surface, through the through-hole wiring. A second ground terminal electrically connected to the first ground terminal, and the attenuating capacitor is connected between the second electrode terminal and the second ground terminal.

  According to a third aspect of the present invention, there is provided a condenser microphone unit in which a diaphragm assembly in which a diaphragm and a fixed pole are arranged to face each other via a spacer is housed in a cartridge case, an impedance converter, an audio A microphone main body in which a power module unit including an output circuit and a polarized power supply circuit is housed in a microphone casing, and the condenser microphone unit is detachable from the microphone main body, and the vibration is interposed between them. In a condenser microphone in which an attenuator having an attenuating capacitor connected in parallel to a capacitor composed of a plate and a fixed pole is detachably interposed, the attenuator is mounted with the attenuating capacitor. Between the condenser microphone unit and the microphone body. It is characterized in that it consists of a circuit board to be.

  According to the present invention, since the attenuation capacitor is mounted on the circuit board sandwiched between the condenser microphone unit and the microphone main body, it can be manufactured at low cost. In addition, since it is sandwiched between the condenser microphone unit and the microphone main body and does not appear in the outer shape of the microphone, it can be shared without giving a sense of incongruity to the design of the condenser microphones of different appearances. Furthermore, since the attenuating capacitor can be easily replaced, it is possible to respond quickly to changes in the specifications of the attenuator.

  Next, an embodiment of the present invention will be described with reference to FIGS. 1 to 3, but the present invention is not limited to this. 1 is an exploded sectional view showing a condenser microphone provided with an attenuator according to the present invention, and FIGS. 2A to 2C are a plan view, a longitudinal sectional view and a bottom view of the attenuator according to the present invention. FIG. 3 is a cross-sectional view showing an assembled state of the condenser microphone.

  First, referring to FIG. 1, a condenser microphone unit 10 and a microphone main body 20 are detachable from this condenser microphone, and an attenuator 30A is interposed between them as necessary.

  The condenser microphone unit 10 may be the same as the conventional example described with reference to FIG. That is, the condenser microphone unit 10 in this example is a unidirectional unit, and has a cylindrical cartridge case 11 having a front acoustic terminal opening 11a on the front side and a rear acoustic terminal opening 11b on the side surface. It has. The cartridge case 11 is made of a metal material such as aluminum or brass alloy.

  In the cartridge case 11, a diaphragm assembly 12 in which a diaphragm 12a and a fixed pole 12b are arranged to face each other via a spacer (not shown) is arranged on the opening 11a side of the front acoustic terminal. A connecting ring 15 having a male screw 15a is integrally attached to the rear end side of the cartridge case 11, and the opening on the rear end side of the cartridge case 11 and the inside of the connecting ring 15 are sealed with insulating materials 16a and 16b. The

  A lead electrode rod 13 that is electrically connected to the fixed pole 12b is provided through the central portion of the insulating materials 16a and 16b. In this example, the extraction electrode rod 13 includes a retractable contact pin 13a biased by a coil spring 13b. The diaphragm 12a is connected to the cartridge case 11 side.

  The microphone main body 20 may be the same as the conventional example described with reference to FIG. 4 and includes a cylindrical microphone casing 21 made of a metal material such as aluminum or brass alloy. On one end side (the upper end side in FIG. 1) of the microphone casing 21, a female screw 21a is formed to be screwed with the male screw 15a of the connecting ring 15, and a lead terminal 25 is provided below the female screw 21a. The formed insulating seat 22 is fitted and fixed.

  An output connector 23 is attached to the lower end side of the microphone casing 21. The output connector 23 is a connector defined in EIAJ RC-5236 “Latch lock type circular connector for audio equipment”, and includes three pins: a ground terminal pin, a signal hot terminal pin, and a signal cold terminal pin. However, for the sake of drawing, only two of the terminal pins 23a and 23b are shown in FIG. The output connector 23 is connected to a phantom power source (both not shown) via a balanced shield cable, and the ground terminal pin is connected to the shield covered wire and the microphone casing 21.

  In the microphone casing 21, the circuit board 24 is accommodated while being supported between the insulating seat 22 and the output connector 23. Although not shown, the circuit board 24 is mounted with a power module unit including an impedance converter (FET), an audio output circuit, and a polarized power supply circuit. The microphone body 20 itself may be referred to as a power module unit.

  In the present invention, the attenuator 30A includes a circuit board 300 punched into a disk shape, as shown in FIGS. The size thereof is substantially the same as the outer diameter of the coupling ring 15 of the condenser microphone unit 10 (the inner diameter of the female screw 21a of the microphone main body 20), and the circuit board 303 is disposed between the condenser microphone unit 10 and the microphone main body 20. Sandwiched between.

  The circuit board 300 is a double-sided circuit board. As shown in FIG. 2A, the circuit board 300 is in contact with the contact pin 13a of the extraction electrode rod 13 at the central portion of one surface (the surface on the condenser microphone unit 10 side) 301. The first electrode terminal 310 is formed. A first ground terminal 311 that contacts the end surface of the connecting ring 15 of the cartridge case 11 is formed in an annular shape around one surface 301 of the circuit board 301.

  As shown in FIG. 2C, a second electrode terminal 320 that contacts the lead terminal 25 is formed at the central portion of the other surface (the surface on the microphone body 20 side) 302 of the circuit board 300, and A second ground terminal 321 is also formed in an annular shape around the other surface 302 of the circuit board 300.

  All of the first electrode terminal 310, the second electrode terminal 320, the first ground terminal 311 and the second ground terminal 321 may be formed of, for example, a copper foil material. The first electrode terminal 310, the second electrode terminal 320 Are electrically connected to each other by the through-hole wiring 303, and the first ground terminal 311 and the second ground terminal 321 are also connected to each other by the through-hole wiring 304.

  As shown in FIGS. 2B and 2C, the attenuating capacitor 305 is preferably formed as a chip component between the second electrode terminal 320 and the second ground terminal 321 on the other surface 302 of the circuit board 300. Connected.

  In the configuration described above, when the attenuator 30A is used, the attenuator 30A is disposed on the insulating seat 22 in the female screw 21a of the microphone body 20, and then the connection ring 15 of the condenser microphone unit 10 is connected to the female screw 21a. Screw in and tighten tightly.

  Thereby, as shown in FIG. 3, the contact pin 13a on the fixed pole 12b side of the condenser microphone unit 10 has an impedance (not shown) via the first electrode terminal 310, the second electrode terminal 320, and the lead terminal 25 of the microphone body 20. Connected to a converter (FET).

  The cartridge case 11 of the condenser microphone unit 10 is electrically connected to the microphone casing 21 on the ground side of the microphone body 20 and functions as a shield case together with the microphone casing 21.

  Then, one pole of the attenuating capacitor 305 is connected to the fixed pole 12b via the second electrode terminal 320, the first electrode terminal 310 and the contact pin 13a, and the other pole is the second ground terminal 321, the first pole. It is connected to the diaphragm 12a via the ground terminal 311 and the cartridge case 11, whereby the damping capacitor 305 is connected in parallel to the capacitor formed by the diaphragm 12a and the fixed pole 12b, and the impedance conversion The audio signal input to the device is attenuated. The amount of attenuation depends on the capacitance of the attenuating capacitor 305.

  Since the attenuator 30A according to the present invention has a simple configuration in which the attenuation capacitor 305 is mounted on the circuit board 300, it can be manufactured at a very low cost. Further, as shown in FIG. 3, since the condenser microphone unit 10 and the microphone main body (power module unit) 20 are sandwiched, there is no difference in appearance from the case where the attenuator 30A is not used. Furthermore, since the attenuation capacitor 305 can be easily replaced, it is possible to respond quickly to a specification change or the like.

  In the above embodiment, the attenuator 30A is arranged on the other surface 302 of the circuit board 300 on the microphone body 20 side. However, the attenuator 30A is disposed on one surface of the circuit board 300 on the condenser microphone unit 10 side. In 301, a connection may be made between the first electrode terminal 310 and the first ground terminal 311. This aspect is also included in the present invention. In this case, the second ground terminal 321 on the other surface 302 side can be omitted.

The disassembled sectional view which decomposes | disassembles and shows the condenser microphone provided with the attenuator by this invention. (A) Top view which shows an example of the attenuator by this invention, (b) The longitudinal cross-sectional view, (c) Bottom view. Sectional drawing which shows the assembly state of the capacitor | condenser microphone of FIG. The disassembled sectional view which shows the condenser microphone provided with the conventional attenuator. Sectional drawing which shows the assembly state of the capacitor | condenser microphone of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Condenser microphone unit 11 Cartridge case 12 Diaphragm assembly 12a Diaphragm 12b Fixed pole 13 Extraction electrode rod 13a Contact pin 15 Connection ring 20 Microphone main body 21 Microphone housing 23 Output connector 24 Circuit board 25 Lead terminal 30A Attenuator 300 Circuit board 305 Attenuating capacitor 310, 320 Electrode terminal 311, 321 Ground terminal

Claims (3)

Power including a condenser microphone unit in which a diaphragm assembly in which a diaphragm and a fixed pole are arranged to face each other via a spacer is housed in a cartridge case, an impedance converter, an audio output circuit, and a polarized power supply circuit Attenuating capacitor that is detachably interposed between a microphone and a module body that is housed in a microphone casing and is connected in parallel to a capacitor constituted by the diaphragm and the fixed pole. In condenser microphone attenuators,
An attenuator for a condenser microphone comprising a circuit board sandwiched between the condenser microphone unit and the microphone body, wherein the attenuating capacitor is mounted on the circuit board.   The circuit board is a double-sided circuit board, and on one surface of the circuit board, a first electrode terminal connected to the lead electrode rod on the condenser microphone unit side is annularly arranged around the one surface, A first ground terminal connected to the cartridge case is formed, and the other surface of the circuit board is electrically connected to the first electrode terminal via a through-hole wiring, and the power module section. A second electrode terminal connected to the lead terminal on the side, and a second ground terminal that is annularly arranged around the other surface and is electrically connected to the first ground terminal through the through-hole wiring 2. The condenser microphone attenuator according to claim 1, wherein the attenuating capacitor is connected between the second electrode terminal and the second ground terminal. Power including a condenser microphone unit in which a diaphragm assembly in which a diaphragm and a fixed pole are arranged to face each other via a spacer is housed in a cartridge case, an impedance converter, an audio output circuit, and a polarized power supply circuit A microphone main body in which a module unit is housed in a microphone casing, and the condenser microphone unit is detachable from the microphone main body, and a capacitor constituted by the diaphragm and a fixed electrode between them. In a condenser microphone in which an attenuator having an attenuating capacitor connected in parallel to the microphone is detachably provided,
A condenser microphone, wherein the attenuator is a circuit board on which the attenuating capacitor is mounted and is sandwiched between the condenser microphone unit and the microphone body.

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