Abstract: A narrow directional stereo microphone includes a narrow directional mid unit disposed such that the directional axis thereof aligns to the major axis of a microphone body, and a unidirectional right unit and a unidirectional left unit disposed symmetrically with respect to the major axis such that directional axes of the right and left units are perpendicular to the major axis, wherein signals output from the mid unit are sent to one of a diaphragm and a fixed electrode of the right unit and to one of a diaphragm and a fixed electrode of the left unit, and right channel signals are output from the other of the diaphragm and the fixed electrode of the right unit, and left channel signals are output from the other of the diaphragm and the fixed electrode of the left unit.

Abstract: A dynamic microphone unit includes: a diaphragm vibrating in response to received sound waves; a voice coil fixed to the diaphragm and vibrating in cooperation with the diaphragm; a magnetic circuit generating magnetism in a magnetic gap, the voice coil being disposed in the magnetic gap; a first air chamber defined adjacent to the reverse of the diaphragm; and a second air chamber defined behind the voice coil, the second air chamber being in communication with the first air chamber, an elastic thin-plate acoustic resistor being disposed in the second air chamber while having tensile force applied, at a position where the acoustic resistor limits the volume of the second air chamber and comes into contact with the voice coil within a maximum displacement of the voice coil.

Abstract: A unidirectional dynamic microphone includes a grip housing, a microphone unit supported at a first end of the grip housing, a plug assembly attached to a second end of the grip housing and connected to the microphone unit through a lead line, and an air room serving as a part of an acoustic circuit of the microphone unit in the grip housing. The grip housing has a fitting part for the plug assembly and an expanded portion. The plug assembly fitted in the fitting part is fixed within the grip housing by an elastic ring and a pressure ring fitted in the expanded portion. The elastic ring seals a space between the grip housing and the plug assembly.

Abstract: A battery compartment for a condenser microphone includes a battery space configured to hold a battery; a battery outlet open to a portion of a peripheral wall of the battery space and allowing removal of the battery in the battery space; a lid covering the battery outlet; and a ribbon having one end portion fixed to an internal wall of the battery space and the other end portion disposed to be pulled out from the battery outlet and wrapping around an external periphery of the battery. The ribbon is conductive and the fixed end portion is grounded.

Abstract: To suppress the transverse displacement of a ribbon due to an impact to a level smaller than that achieved by electromagnetic damping. The switch 150 breaks a path between the piezoelectric element 140 and the secondary winding 132 so as to be non-conductive when a power plug is connected (the microphone is in use), and completes a path between the piezoelectric element 140 and the secondary winding 132 so as to be conductive when a power plug is not connected (the microphone is not in use), in order to generate a driving force in the direction opposite to the displacement direction of the ribbon 10 by causing a current corresponding to power generated in the piezoelectric element 140 to flow in the ribbon 10.

Abstract: There is provided a narrow directional condenser microphone having an acoustic tube, in which a condenser microphone unit having a large effective diaphragm area is arranged on the rear end portion side of the acoustic tube to achieve high sensitivity without an increase in the diameter of the acoustic tube. In a narrow directional condenser microphone in which a unidirectional condenser microphone unit configured by arranging a diaphragm and a backplate opposedly via a spacer is arranged on the rear end side of an acoustic tube 10, the narrow directional condenser microphone is provided with a unit pair assembly 20 configured by opposedly combining two of the condenser microphone units 20R and 20L with the diaphragm side thereof being parallel to each other, and the unit pair assembly 20 is arranged on the rear end side of the acoustic tube 10 in such a manner that the condenser microphone units 20R and 20L are arranged symmetrically with respect to the tube axis X of the acoustic tube 10.

Abstract: A dynamic microphone unit has a diaphragm 5 vibrating in response to sound waves, a voice coil 6 fixed to the diaphragm 5 and vibrating in cooperation with the diaphragm 5, a magnetic circuit including a magnetic gap around the voice coil 6 and generating a magnetic field in a magnetic gap, a first air chamber 11 adjacent to the reverse of the diaphragm 5 holding an acoustic resistance therein, a second air chamber 9 behind the voice coil, and a communication passage 22 for sound waves between the first air chamber 11 and the second air chamber 9.

Abstract: A unidirectional microphone is provided that has an excellent directional frequency response and a high sensitivity. Sound waves are guided to a rear acoustic terminal 10b of an acoustic resistance tube 30 through an acoustic resistance member 31. A rear end opening 30b of the acoustic resistance tube 30 is blocked so as to prevent the sound waves from entering the rear acoustic terminal 10b from the rear end opening 30b of the acoustic resistance tube 30 on the side of the rear acoustic terminal 10b. A gap G which allows low-frequency sound waves to pass and through which a front acoustic chamber A1 and a rear acoustic chamber A2 in the acoustic resistance tube 30 communicate with each other is provided between the inner peripheral surface of the acoustic resistance tube 30 and the outer peripheral surface of the microphone unit 10.

Abstract: This invention provides a condenser microphone unit having a diaphragm assembly in which a diaphragm does not attach to a fixed electrode even if a polarization voltage is increased. A condenser microphone unit is provided having a diaphragm assembly 1 in which a diaphragm 12 is stretched over a diaphragm support 10 and a fixed electrode 20 arranged to face the diaphragm assembly 1 through a spacer. An opening 10a over which the diaphragm 12 is stretched so as to be able to vibrate is formed in the diaphragm support 10, the diaphragm 12 is stretched over the diaphragm support 10 in a situation where a central part of the diaphragm is dented to be concave, and the concave is arranged to face the fixed electrode 20.

Abstract: To provide electromagnetic damping without a special output connector for protecting a diaphragm of metallic ribbon foil of a ribbon microphone against shocks. A ribbon microphone operable with a phantom power supply comprises: an acoustic-electric converter 1 including a pair of permanent magnets and a diaphragm of metallic ribbon foil; and a step-up transformer 110 coupled with the diaphragm on a primary winding 111 side and having, on a secondary winding 112 side, an output connector 120 removably connected to a phantom power supply, the step-up transformer 110 increasing a voltage generated by the diaphragm to a predetermined voltage, the voltage then being output to the phantom power supply side through the output connector 120, wherein a switch 141 is connected across the secondary winding 112, the switch 141 being normally closed and being opened by a power supplied from the phantom power supply.

Abstract: In a diaphragm of an electric sound converter which converts vibration such as sound into an electrical signal, a center dome is reinforced while suppressing variations in the sensitivity and frequency response to the minimum, whereby reduction in a high-pass reproduction limit is suppressed, and occurrence of anomalous resonance is prevented. In a diaphragm 1 of an electric sound converter having a center dome 2, a reinforcing film 7 made of the same material as that of the center dome and formed into the same shape as that of the center dome is applied to the center dome with a hot-melt adhesive 6 of the same nature as that of the center dome, a groove 7a formed in a polygonal reticulate pattern is provided on one surface of the reinforcing film adhered with the adhesive, and a convex rib 8 corresponding to the groove is formed on the other surface.

Abstract: A condenser microphone unit includes a diaphragm, a diaphragm ring, a fixed electrode, a casing unit accommodating the diaphragm ring, the diaphragm, and the fixed electrode. A condenser microphone includes the condenser microphone unit. The diaphragm ring is indirectly fixed to the interior of the unit casing through a fixing ring fixed to the unit casing. The fixing ring has a planar ring portion and a plurality of projections projecting from the internal periphery of the ring portion and provided in a circumferential direction. The plurality of projections urges the diaphragm ring toward the fixed electrode.

Abstract: A dynamic microphone unit includes a diaphragm vibrating in response to received sound waves; a voice coil fixed to the diaphragm; a magnetic circuit generating magnetism in a magnetic gap where the voice coil is disposed; and an acoustic resistor disposed in a space adjacent to the reverse of the diaphragm. The acoustic resistor includes a cover disposed between a felt and the diaphragm. A case having an open end and a closed end accommodates the felt and the cover. The cover has holes transmitting sound waves at the closed end and a bending portion at the open end which urges the cover and the felt.

Abstract: A condenser microphone has an output circuit comprising an emitter-follower circuit; an impedance converter comprising an FET and at least one transistor of the emitter-follower circuit provided next to the FET; and the transistor having an emitter terminal provided with a constant-voltage circuit. The FET included in the impedance converter is operated by a voltage supplied from the constant-voltage circuit.

Abstract: A condenser microphone includes a volume restrictor disposed in a space inside a microphone case and an electronic circuit disposed in the space and encompassed by the volume restrictor. The volume restrictor reduces the volume of the space and prevents sound waves entering the space through openings on the microphone case from reaching the electronic circuit.

Abstract: A condenser microphone outputs a signal resistive to distortion caused by an excess input without a variation in signal-to-noise ratio. The microphone includes a first condenser microphone unit and a second condenser microphone unit that generate output signals having phases opposite to each other; and a twin variable resistor connected to an output terminal of each of the first and second condenser microphone units. In the microphone, the output signal of the first unit is combined with the output signal of the second unit in a first variable resistor included in the twin variable resistor and the composite signal is applied to an input of the first unit, and the output signal of the first unit is combined with the output signal of the second unit in a second variable resistor included in the twin variable resistor and the composite signal is applied to an input of the second unit.

Abstract: A cap body 3 is provided for covering a housing of a microphone body 2. The cap body 3 has an insertion hole 32 into which the housing is inserted, sound collecting holes 31a and 31b through which the exterior of the cap body 3 is in communication with the insertion hole 32. While the housing is inserted into the insertion hole 32, a sound collector 21 lies in the insertion hole 32, and the axis line direction of the sound collecting holes 31a and 31b are different from the directive axis of the microphone body 2 of which the housing is inserted in the insertion hole 32.

Abstract: The present invention provides a unidirectional microphone by adding an output from an omnidirectional condenser microphone unit and an output from a bi-directional ribbon microphone unit together. A condenser microphone unit 10 and a ribbon microphone unit 20 are connected in series via a step-up transformer 30, and the respective sound signals from the microphone units 10 and 20 are added together and are output from a source S of an FET 14.

Abstract: A ribbon microphone unit includes a pair of magnets generating a magnetic field, a ribbon diaphragm disposed in the magnetic field generated by the magnets, and a circuit substrate provided with signal paths that conduct electrical signals generated by vibration of the ribbon diaphragm to output terminals. The signal paths are symmetrical about the longitudinal central axis of the ribbon diaphragm.

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.