Abstract: A condenser microphone includes a unit case that supports a condenser microphone unit, has an internal space in communication with a rear acoustic terminal of the microphone unit, and has an opening in a peripheral wall in communication with the internal space; a volume restrictor that reduces the volume of the internal space by partitioning the internal space; a circuit board disposed in the internal space and surrounded by the volume restrictor; and a rigid conductor that electrically connects a signal output terminal of the microphone unit and the circuit board. The circuit board intersects the center axis of the unit case. The rigid conductor is supported such that the rigid conductor slides along the volume restrictor. An elastic conductor is compressed between the rigid conductor and the circuit board or between the rigid conductor and the signal output terminal of the microphone unit.

Abstract: A microphone includes an output controller 14 to control output from a microphone unit 10, a metal portion 20 of an outer casing of the microphone, a neon tube 24 to discharge static electricity from an external object through the metal portion 20, and an acoustic coupler 30 to control the output controller 14 through generation of sound in response to a discharge current from the neon tube 24 and detection of the sound.

Abstract: Provided is a dynamic headphone that has a small size but makes a larger-diameter headphone unit mountable thereon, the dynamic headphone including a highly reliable acoustic channel that acoustically connects a front air chamber and a back air chamber to each other. A headphone case 20 houses a headphone unit 50 therein, and includes a back air chamber C2 on a back side of the headphone unit 50. The headphone case 20 includes: a back air chamber forming portion 40 that forms the back air chamber C2; and a mount portion 30 integrally provided to an opening end of the back air chamber forming portion 40, the headphone unit 50 being mounted in the mount portion 30. An acoustic channel 70 is provided between the mount portion 30 and the headphone unit 50.

Abstract: A unidirectional condenser microphone includes a front acoustic terminal disposed on a forward portion of a microphone case, a rear acoustic terminal disposed on the outer circumferential surface of the microphone case, and a directionality varying member disposed on the outer circumferential surface of the microphone case. The directionality varying member switches between a first position and a second position. The directionality varying member covers the rear acoustic terminal at the first position while the rear acoustic terminal is opened at the second position. The front acoustic terminal is displaced ahead of the front surface of the microphone case, and the directionality varying member is in close contact with the outer circumferential surface of the microphone case.

Abstract: A condenser microphone includes a condenser microphone unit having a diaphragm and a fixed electrode disposed opposite to the diaphragm; a field effect transistor serving as an impedance converter; and a transistor to generate operational power for the field effect transistor; wherein the field effect transistor comprises a gate, a source and a drain, the gate is connected to the fixed electrode or the diaphragm, the diaphragm disposed opposite to the fixed electrode connected to the gate or the fixed electrode facing the diaphragm connected to the gate is grounded; the source is connected to a base of the transistor; the drain is connected to an emitter of the transistor; and a resistor establishing a base potential of the transistor is disposed between the base of the transistor and a ground.

Abstract: A throat microphone includes a cantilevered piezoelectric device 1 having a fixed end 11 supported by a base 3 and a free end with an anchor 4 fixed thereto. The piezoelectric device 1 vibrates to output audio signals in response to vibrations of a throat. The fixed end is attached to the base 3 such that the piezoelectric device 1 vibrates parallel to the surface of the base 3. A gap is defined between the anchor 4 and the base 3. The gap is provided with a vibration absorber 5.

Abstract: The electret condenser microphone according to the present invention includes an electret condenser microphone unit including a diaphragm and a fixed pole disposed opposite to the diaphragm; and a three-pin plug including a hot terminal and a cold terminal and being capable of producing a balanced output, wherein each of the hot terminal and the cold terminal is coupled to an FET that functions as an impedance converter a gate terminal of one of the FETs is coupled to the diaphragm, a gate terminal of the other of the FETs is coupled to the fixed pole, and the gate terminal of the FET coupled to the cold terminal is AC-grounded.

Abstract: The present invention has: a condenser microphone unit which performs electroacoustic conversion according to a change in an electrostatic capacitance between a diaphragm and a fixed pole; a non-inverting amplifier which is connected to one of the diaphragm and the fixed pole, and which has an impedance converter which converts an output impedance of the microphone unit into a low impedance; an inverting amplifier which receives an input of an output signal of the non-inverting amplifier through an input resistance, and which has a feedback resistance; and a variable resistor which is connected between an output of the non-inverting amplifier and an output of the inverting amplifier, and in which a wiper is connected to the diaphragm or the fixed pole, whichever is not connected to the non-inverting amplifier, and the sensitivity changes according to the position of the wiper of the variable resistor.

Abstract: In an electrodynamic acoustic transducer which uses a surface potential of an electret dielectric film as a polarization voltage, prevention of partial suctional adhesion of a diaphragm caused by variation in surface potential across the electret dielectric film is ensured in a simple way. In an electrodynamic acoustic transducer including a diaphragm and a fixed pole which are arranged with a predetermined interval so as to face each other, a facing surface of either one of the diaphragm and the fixed pole having an electret dielectric film, a surface of the electret dielectric film is divided into a plurality of segment regions, and a predetermined surface potential is given to each of the segment regions by a polarization processing unit.

Abstract: When a diaphragm formed in the shape of an oval is held by a holding member, an electrostatic electroacoustic transducer which allows stable tension without a diaphragm flexing is provided. In the electrostatic electroacoustic transducer, a diaphragm 11 and a diaphragm holding member 12 are formed in the shape of an oval, and is provided with a corrector member 21 which presses inwardly from outside both side ends on a major axis of the oval diaphragm holding member, and opens and deforms outwardly a pair of opposed long sides 12a and 12b on a minor axis side of the diaphragm holding member.

Abstract: There is provided a microphone device with which an operation state of the microphone device may be easily checked and that may effectively reduce noise to be played back, the noise being caused by vibration that has propagated through a table or the like. A microphone device is configured such that a microphone case 2 in which a microphone unit 3 for converting a speech wave into a speech signal is housed is supported by a stand arm 25 via a coupling member 11 formed of a light-transmissive elastic material, and light emitted from a light source (LED) 14 housed in the microphone case 2 or the stand arm 25 is projected to an outside through the coupling member. Control is performed such that the light source 14 is lit in an on state in which a speech signal is output from the microphone unit 3.

Abstract: An electroacoustic transducer includes a diaphragm, an electroacoustic transducer unit having the diaphragm, and an air chamber having the diaphragm of the electroacoustic transducer unit and having a variable volume in response to vibration of the diaphragm. The air chamber has a sound pressure detector detecting a sound pressure in the air chamber and a volume adjuster driven by the output signals from the sound pressure detector, changing the volume of the air chamber in response to the output signals, and controlling the acoustic impedance of the air chamber. A control system from the sound pressure detector to the volume adjuster configures a feedback control system increasing the volume of the air chamber with an increase in the sound pressure in the air chamber.

Abstract: A gooseneck microphone has a configuration capable of preventing both of the occurrence of noise caused by extraneous electromagnetic waves and the occurrence of noise caused by electric discharge when touched. The gooseneck microphone includes a microphone unit having an electrostatic acousto-electric converter and a metal unit casing; a unit holder having a circuit board mounted with an impedance converter electrically connected to an output side of the acousto-electric converter, a cylindrical outer cylinder body, a cylindrical inner cylinder body arranged in the outer cylinder body, and a synthetic resin cover member covering the outer cylinder body; a metal support pipe having flexibility, the unit holder being supported on one end side of the support pipe; and a microphone cable having a two-core shield covering cable and inserted through the support pipe, one end side of the microphone cable being brought into the unit holder.

Abstract: A narrow directional microphone including a film for suppressing wind noise capable of being displaced by a wind pressure, a unidirectional microphone unit having a front acoustic terminal, a cylindrical acoustic tube having a prescribed axial length, and an acoustic resistor disposed at a position which is on an outward side of the film and at which the resistor does not come into contact with the film even when the film is displaced by the wind pressure. A rear end of the acoustic tube is coupled to a side of the front acoustic terminal of the unidirectional microphone unit, and a front end opening of the acoustic tube is covered with the film.

Abstract: A stereo microphone has four condenser microphone units having respective directional axes in the same horizontal plane. The four units each have unidirectivity and a quadrangular shape viewed from the direction of the directional axis. The units are disposed by rotating the directional axes of adjacent units by 90°. A pair of two units diagonally positioned and having the directional axes directed at 180° to each other collaborate with each other to form a pair of bidirectional microphone units.

Abstract: A microphone includes a polar piece contacting with a first magnetic pole of a first permanent magnet, a yoke body annularly arranged around the polar piece through a magnetic gap G with a predetermined width, a magnetic circuit unit including a tail yoke connected to the yoke body and contacting with a second magnetic pole of the first permanent magnet, and a diaphragm unit provided with a voice coil arranged to vibrate in the magnetic gap. The second magnetic pole of the first permanent magnet contacts with one side of the tail yoke, a first magnetic pole of the second permanent magnet is disposed to contact with other side of the tail yoke, a magnetic path is produced between the second magnetic pole of the second permanent magnet and the yoke body, and the first permanent magnet and the second permanent magnet are polarized in the same sense.

Abstract: Provided is a narrow-angle directional microphone in which a microphone unit is attached to an acoustic tube, the acoustic tube is accommodated a microphone case and which prevents the rattling of components provided in the microphone case and has high mechanical strength. A narrow-angle directional microphone 1 includes a microphone unit 2, an acoustic tube 3 that has an opening formed in a circumferential wall along an axis direction and a rear end to which the microphone unit is connected, a cylindrical microphone case 4 that accommodates the acoustic tube, and fixing means 3a, 4a, 10, and 20a that fix the acoustic tube in the microphone case, with stress being applied to the acoustic tube in the microphone case in the axis direction from the leading end side of the acoustic tube using the rear end of the acoustic tube as a fulcrum.

Abstract: A ribbon microphone circuit includes a ribbon microphone unit; a step-up transformer; buffer amplifier circuits connected to a secondary winding of the step-up transformer; an external power supply circuit as a power source for driving the buffer amplifier circuits; and a switch circuit including photo-relays having lights that are turned on while the external power source is being supplied and having contacts operating depending on states of the respective lights, wherein signals output from the ribbon microphone unit are sent through the buffer amplifier circuits while the external power source is being supplied, and sent without passing through the buffer amplifier circuits while the external power source is being not supplied.

Abstract: A microphone adapter is attachable to a microphone including a microphone unit and a casing having a front sound terminal and a back sound terminal. The microphone adapter has a bottom having a hole through which the casing of the microphone extends and a cylindrical peripheral wall integrated with the bottom, having an open end opposite to the bottom, and covering the periphery of the back sound terminal. The cylindrical peripheral wall has an internal diameter larger than the external diameter of the casing of the microphone so as to define a space between the cylindrical peripheral wall and the external peripheral surface of the casing of the microphone extending through the hole, and extends from the bottom at least to a position of the front sound terminal in a sound collection axis direction.

Abstract: A handheld condenser microphone is provided with a condenser microphone unit having two unidirectional condenser elements. A conductive fabric 221 is put between a lock ring 213 and the second condenser element 10b, when an acoustic-electric transducer 220 is fixed inside a unit case 210 by fastening force of the lock ring 213.