Abstract: An electrostatic speaker is constituted of a vibrator, conductive cloths, and elastic members, which are laminated together and woven together using strings. Since all the constituent elements are restrained in positioning by strings, the overall structure thereof is not substantially changed even when the electrostatic speaker is deformed in shape by bending or curving, wherein it is possible to secure the prescribed positional relationship between the constituent elements, which are not deviated in positioning. It is possible to introduce a sheet composed of a thermoplastic resin, which holds the vibrator and elastic members therein. The conductive cloths can be replaced with film electrodes, each of which is formed such that a conductive polymer layer is formed on a base film composed of a thermoplastic resin.

Abstract: An electrostatic speaker is constituted of a vibrator, conductive cloths, and elastic members, which are laminated together and woven together using strings. Since all the constituent elements are restrained in positioning by strings, the overall structure thereof is not substantially changed even when the electrostatic speaker is deformed in shape by bending or curving, wherein it is possible to secure the prescribed positional relationship between the constituent elements, which are not deviated in positioning. It is possible to introduce a sheet composed of a thermoplastic resin, which holds the vibrator and elastic members therein. The conductive cloths can be replaced with film electrodes, each of which is formed such that a conductive polymer layer is formed on a base film composed of a thermoplastic resin.

Abstract: An electrostatic speaker is constituted of a vibrator, conductive cloths, and elastic members, which are laminated together and woven together using strings. Since all the constituent elements are restrained in positioning by strings, the overall structure thereof is not substantially changed even when the electrostatic speaker is deformed in shape by bending or curving, wherein it is possible to secure the prescribed positional relationship between the constituent elements, which are not deviated in positioning. It is possible to introduce a sheet composed of a thermoplastic resin, which holds the vibrator and elastic members therein. The conductive cloths can be replaced with film electrodes, each of which is formed such that a conductive polymer layer is formed on a base film composed of a thermoplastic resin.

Abstract: An electrostatic speaker is constituted of a vibrator held between opposite electrodes via spacers. The vibrator has a plurality of surface projections and a plurality of backside projections, which project in opposite directions. When voltage differences occur between the opposite electrodes due to audio signals, electrostatic force is exerted on the vibrator, which thus vibrates in response to audio signals with a high sensitivity. The vibrator 10 generates sound in response to vibration parameters such as vibration frequency, amplitude, and phase. The sound propagates through at least one of the opposite electrodes having small holes and is thus emitted to the external space. Thus, it is possible to precisely reproduce sound with a high sensitivity to audio signals and without causing distortions in reproduction waves.

Abstract: A speaker array apparatus capable of performing control to narrow the directivity angle of low-frequency range sounds, without causing a speaker array to be large in size. An audio signal input to the speaker array apparatus is divided into an audio signal in which low-frequency range components of the input audio signal are included and an audio signal in which low-frequency range components thereof are attenuated, and the former audio signal is signal-processed by a directivity controller. Based on the processed audio signal, sounds are emitted from speakers disposed at four corners of the speaker array, whereby the directivity angle of acoustic beam in low-frequency range can be made narrower than when sounds are emitted from all the speakers of the speaker array.

Abstract: An electrostatic speaker capable of relaxing a restriction on the allowable amplitude of a diaphragm while maintaining the linearity of a force acting on the diaphragm. The electrostatic speaker mainly includes electrodes opposed to each other, a diaphragm, and elastic members interposed between the diaphragm and the electrodes. The elastic members have an elastic characteristic that generates a restorative force corresponding to higher order terms of an electrostatic force generated by the electrodes and acting on the diaphragm.

Abstract: In order to provide a sound-absorbing material and a sound-absorbing panel which can be produce at a low-cost and have excellent beauty or appearance and excellent sound-absorbing characteristics, the sound-absorbing material is applied which is made from a metallic plate member (2), and multiple pierced apertures of 200 ?m or smaller diameter are arranged along a board thickness on the plate-shaped member (2).

Abstract: A band comprising many beam portions and arcuate hinge portions formed integrally so as to be alternately arranged, a fitting force being obtained at least due to the returning force of the hinge portion so that the band can be expanded even with a small force and, in spite of the repeated use over a long period, the fitting force and winding action will not deteriorate and the band will not crack. The bands are connected symmetrically to both ends of a top band and are utilized as head bands for headphones.

Abstract: A planar type electro-acoustic transducer having a disk-like inner diaphragm member to the top end inner side of a voice coil bobbin, and having an annular outer diaphragm member concentric with said inner diaphragm member and conjugated to the top end outer side of the voice coil bobbin, in such way that these two diaphragm members jointly constitute a single planar type diaphragm. This arrangement increases the conjugation strength of the diaphragm members to the voice coil bobbin and also enables a new manufacturing process for the transducer in which the diaphragm and the coil bobbin are easily centered.

Abstract: An electro-acoustic transducer comprises a planar type diaphragm having a circular voice coil formed on its surface and a magnet plate assigned for magnetically biasing said voice coil, said circular voice coil having a plurality of circular turns formed with a pattern that the respective circular turns of the circular coil are concentric to each other in at least one half portions of these turns. This arrangement of transducer makes its assembling or the positioning of the voice coil and the magnet plate extremely easy without degrading the output capability of the transducer.

Abstract: In an electro-acoustic transducer in a loud speaker and like devices, a diaphragm and/or a voice coil bobbin is or are formed by a composite material consisting of a foamed resin containing reinforcing fibers. Such diaphragm has a large Young's modulus-to-density ratio E/.rho., a large internal loss tan.delta. and a large flexural rigidity E.I, and thus it exhibits good characteristics in sound reproducing. Such voice coil bobbin which is an electric insulator can have a small thickness and is light in weight and has a large mechanical strength, and thus it is free from adversely affecting the vibration of the diaphragm, and accordingly, the sound reproduced.

Abstract: A diaphragm for electro-acoustic transducer which, as a component member, utilizes a layer of ceramics material, by which the E/.rho. ratio of the diaphragm can be increased, leading to an elevated resonance frequency of the diaphragm, whereby the limit frequency for reproducting of high-pitch sound can be shifted high, thus making it possible to widen the range of piston motion of the diaphragm, and to thereby improve its frequency characteristic. Also, a diaphragm utilizing a composite board formed by lamination of a layer of ceramics material and a layer of light-weight metal eliminates the fragility of diaphragm would entail when the diaphragm utilizes a single layer of a ceramics material alone, and thus the handling of the diaphragm is facilitated.

Abstract: A planar type electroacoustic transducer comprising a diaphragm; at least one magnet plate on which are formed a plurality of mutually different and spaced magnetic poles in a matrix shape of columns and rows so as to face the diaphragm at a distance enough to involve the facing surface of the diaphragm within magnetic fields associated with the magnetic poles; and an electric conductor formed on the diaphragm to run in alternate directions of a column and a row along a path corresponding to the spaces defined between the respective magnetic poles without straightforwardly passing by any two magnetic poles of a same column or row. This diaphragm may be provided with ribs to further minimize the development of partial vibrations of the diaphragm. Those portions of the conductor running in regions of weak magnetic fields may have an enlarged size or smaller length to reduce the impedance of the conductor.

Abstract: A diaphragm for electro-acoustic transducer comprising a core member of honeycomb structure made of either a thin film of a metal or a high molecular material, and a skin member bonded to at least one side of this honeycomb core structure and being prepared by the use of aromatic polyamide fibers having a high tensile strength, a high Young's modulus and a high Young's modulus-to-weight ratio and reinforced by a thermo-setting resin. Such diaphragm has a high Young's modulus, an improved mechanical strength and a wide frequency range of piston motion, and presents reduced distortion throughout a wide frequency range, and has a superior transition characteristic, whereby a good sound reproduction characteristic is obtained.

Abstract: A headphone comprising: two ear cups; a head band; and coupling means for rotatably coupling the ear cups to the head band, the ear cups having ear pads on those sides facing each other, respectively, the head band being positioned on that side of each of the ear cups away from the side where the ear pad is provided, said coupling means rotatably coupling the head band to that side of each of the ear cups located away from the side where the ear pad is provided, whereby the coupling means enables each of the ear cups to make vertical and horizontal rotations relative to the ear of the user. This headphone insures free rotation of the ear cups in universal directions, and the rotation angle can be controlled as required. Moreover, the headphone as a whole can be provided in a compact size.