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: A dynamic microphone unit includes a diaphragm vibrating upon receiving acoustic waves, a voice coil fixed to the diaphragm, vibrating together with the diaphragm, a magnetic circuit generating a magnetic field in a magnetic gap in which the voice coil is disposed, a rear air chamber formed behind the magnetic circuit, wherein holes for connecting a back side space of the diaphragm with the rear air chamber are formed in a member forming the magnetic circuit in order to reduce resonance and reduce peaks developing in frequency response characteristics, achieving uniformity of directivity.

Abstract: A stereo ribbon microphone includes four ribbon microphone units disposed in a circle on a single horizontal plane. The ribbon microphone units are alternately assigned to a right channel and a left channel along the circumferential of the circle.

Abstract: A microphone includes a switch that turns on and off an audio signal; light sources that are turned on and off in response to the operation of the switch; a light-incident portion that receives light from the light sources; a light guide that directs the light in the longitudinal direction; and a light radiator having a light diffuser that diffuses light. The light guide has a thickness that decreases with the distance from the light-entering portions.

Abstract: An output circuit of a bidirectional side microphone element includes an inverting amplifier inverting a phase and outputting an inverted signal, adds a non-inverted output signal of the side microphone element to an output signal of a middle microphone element having unidirectivity to produce a signal for one channel of the left and right channels; and adds an inverted output signal of the side microphone element being the output signal from the inverting amplifier to the output signal of the middle microphone element to produce another signal for the other channel. An input resistor and a feedback resistor to the inverting amplifier are dividable. The division ratio of the input resistor to the feedback resistor is varied to change the levels of the non-inverted output signal and the inverted output signal of the side microphone element, and to change the angle between the left and right directional axes.

Abstract: A microphone comprises a microphone unit; and a HOT terminal and a COLD terminal that produce a balanced output of output signals of the microphone unit, and no filter circuit is disposed between the microphone unit and the HOT terminal and a low-pass filter is disposed only between the microphone unit and the COLD terminal.

Abstract: A stereo microphone includes a nondirectional microphone unit and two bidirectional microphone units, the bidirectional microphone units having directional axes disposed on a single plane at predetermined angles to the center axis of the directionality of the stereo microphone, an acoustic terminal of the nondirectional microphone unit being disposed in the vicinity of acoustic terminals of the bidirectional microphone units.

Abstract: A dynamic headphone unit includes a diaphragm to which a voice coil is fixed, a permanent magnet, a pole piece disposed adjacent one of the magnetic poles of the permanent magnet, and a yoke disposed adjacent the other magnetic pole of the permanent magnet. The pole piece and the yoke define a magnetic gap therebetween, and the voice coil is vibratably supported by the diaphragm in the magnetic gap. The voice coil includes a lead line for transmitting signal current. The lead line is bonded to the inner surface of a peripheral dome of the diaphragm with a pressure-sensitive adhesive.

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 ribbon microphone includes a ribbon microphone unit; an acoustic box for mounting a rear acoustic terminal of the ribbon microphone unit; a detective microphone mounted in the acoustic box, the detective microphone detecting sound waves identical to sound waves guided to the rear acoustic terminal of the ribbon microphone unit; a speaker comprising a diaphragm, the speaker being assembled in the acoustic box and varying the pressure in the acoustic box in response to the driven diaphragm; and a drive unit for driving the speaker so as to cancel a variation in pressure in the acoustic box in response to signals detected by the detective microphone, the variation being caused by sound waves guided to the rear acoustic terminal. This configuration extracts an omnidirectional component without an acoustic tube to achieve a small high-sensitivity unidirectional ribbon microphone and a unidirectional converter for the ribbon microphone.

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: 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 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: 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: 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: 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.