Abstract: A stereophonic microphone system for improving stereophonic hearing utilizes intensity stereophonic and/or time difference stereophonic pickup methods with the use of replicas of the human head. The microphones are mounted in the replicas of the outer auditory meatus. The replica of the human head is limited to replicas of the pinna with outer auditory meatus. In addition to the known stereophonic recording device used as a position association stage, two replicas of human pinnas are used, with pressure microphones in each opening of the auditory meatus as a shape association stage. The pinna replicas are arranged spaced apart and oriented on the human head or closely next to each other with the same orientation. The pinna replicas are arranged preferably immediately adjacent the arrangement of known directional microphones for the interaural sound recording in the horizontal and median planes.

Abstract: A device for the stereophonic recording of sound events by means of two microphones arranged with essentially oppositely directed orientation and mounted in replicas of the human head. The microphones are mounted in the replicas of the outer auditory meatus. The replica of the human head is limited to the replicas of the pinnae with the outer auditory meatus. Microphones with unilateral pickup effect are used and are mounted preferably in positions corresponding to the positions of the pinna openings in human heads. The microphones operate in the low-frequency range of up to approximately 1500 Hz as directional microphones and, in the frequency range above approximately 1500 Hz, operate with spectral resolution of the outer ear transmission function. The device according to the present invention provides compatibility of headset reproduction and loudspeaker reproduction.

Abstract: An eyeglass frame and electroacoustic device combination for the improvement of natural hearing has temples that contain or carry electronic and electroacoustic devices. To enable persons with reduced hearing to again be able to follow a conversation in noisy surroundings, e.g. to concentrate on a partner during a cocktail party situation, to clearly understand speech in reverberant rooms, to concentrate on sound from a specific direction, to enjoy again theater and concert performances, each temple of the eyeglass frame comprises, directly at its front end, a directional microphone. The direction of maximum sensitivity extends to the front of the wearer, and its direction of minimal sensitivity faces toward the electroacoustic transducer at the rear end of the temple, near the ear of the wearer. This electroacoustic transducer is arranged at the rear end of the temple on an arm of a temple.

Abstract: An ear pad for earphones comprises a foam-like material formed into a pad enclosing the user's ear in use in order to expand the essentially linear frequency response of a good earphone so that it brings also the lowest still audible frequencies into the linear region, and simultaneously with the expansion of the transmission range of the earphone, to make the reproduction of stereophonic acoustic events more natural. The ear pad is advantageously shaped and made of open-cell elastic foam material having on its inner and/or its outer side or in its interior so as to be disposed in the sound path from the coupling space outward, at least one passive membrane supported for vibration and having a natural resonance which lies in the range of the lower frequencies.

Abstract: A headband comprises first and second headbands having their one ends pivotally interconnected and being foldable about their pivotal interconnection inwardly and outwardly in a single plane and having opposite ends with an earpiece carried thereby. Each of the headbands include at least three separate parts telescopically interengageable and which are of substantially equal lengths. Advantageously the central part may be made of plastic and includes a tubular portion into which the next adjacent part is telescopical. The tubular portions are advantageously provided at each end of the central part to permit a telescopic movement of each of the other parts into the middle part.

Abstract: A microphone for receiving acoustic vents stereophonically in accordance with a center-side method comprises a plurality of transducers including at least one having a unilateral directional characteristic particularly cardioid or hypercardioid and at least two other electroacoustic transducers having a figure-eight characteristic which are associated with the unidirectional characteristic transducer and have principal axes at right angles to the main axes of the unidirectional transducer. A common line connects a terminal of each of the three transducers and a connecting line interconnects a respective terminal of each. In addition, the connecting line between the two electroacoustic transducers having a figure-eight characteristic include control means comprising either a switch or a controller.

Abstract: Headphone earpieces which comprise each at least one electroacoustic transducer operating on the orthodynamic principle and including a small-mass diaphragm of an extension corresponding at least to that of an average auricle, with the coupling space of each of the earpieces being designed for a minimum reflection, are equipped with an ear cushion which, with the headphone in position of use, tightly encloses the coupling space toward the outside.

Abstract: An electroacoustic transducer of the electrodynamic type comprises a flat magnetic system permeable to sound including a diaphragm with conducting tracks which are disposed within the system which has a mass provided with conducting tracks substantially equal to the mass of a diaphragm of equal size intended for capacitive transducers. The construction includes acoustic group delay time elements coupled to the diaphragm and a housing defining a shallow depth air chamber at one side of the diaphragm to give the transducer the form of a sound receiver with a unidirectional characteristic.

Abstract: In a diaphragm arrangement for electroacoustical transducers, in particular for headsets, one or more diaphragms lie in one plane which extends in the immediate proximity of the user's external ear and preferably parallel to the tangential plane of the user's external ear. In order to enable the use of the headset to better discern direction and distance by hearing, the diaphragm is divided into several coherent, preferably stripshaped sections or composed of several, preferably stripshaped part diaphragms which are adjacent or follow each other in that particular direction in which the user's ear is to locate the direction of sound incidence in the use position.

Abstract: An earphone construction for a wearer's ear, comprises an ear pad which is adapted to surround the ear and is advantageously constructed of a wedge-shaped tapered configuration and of annular form so that the inner edge bounding the inside of the ear along the cheekbone is of a narrower width than the outer portion and the outer portion tapers downwardly from the wide portion bounding the upper part of the ear to a lower portion adjacent the lower part of the ear which does not project outwardly from the head as much as the upper portion. At least one electroacoustic transducer is provided which includes a diaphragm which is surface-driven and which is mounted in, and supported at its periphery, on a transducer frame connected to the ear pad. The diaphragm is thus supported by the frame which also supports ferromagnetic plates on each side of the diaphragm having magnetic rods which are spaced from the respective sides of the diaphragm.

Abstract: A device for reproducing acoustic events carried on at least two channels, in a room with at least two sidewalls, comprising, at least one first sound-radiating transducer positioned to radiate sound toward a listener with at least two second sound-radiating transducers positioned in association with the first sound-radiating transducer and for radiating sound toward the at least two sidewalls, respectively. The two channels carrying the acoustic event are supplied to the first and second transducers so that the first transducer receives both channels and each of the second transducers receives one of the two channels. The listener thus receives sound waves from the two second transducers with delay. A delay device may also be connected to the two second sound transducers for producing an additional delay in the first and second channels supplied thereto.

Abstract: An earphone comprises a housing including a partition plate with an opening containing a diaphragm. An annular cushion is secured to the periphery of the partition and engages around the wearer's ear to form a coupling space between the diaphragm and the ear. A back covering is connected to the partition defining a soundproof cavity between the partition and the back covering. A partial wall is spaced from the partition on a side opposite the diaphragm to define a first high restoring force cavity. A duct is connected from the restoring force cavity to the outside, and it encloses an air mass which acts as an acoustic mass.

Abstract: The headphone includes a cup-shaped case forming the coupling space and this cup-shaped case, in use, engages the user's head and encloses the user's ear. At least one electroacoustic transducer is included in the cup-shaped case, and the case either is designed as an acoustic frictional resistance or as a supporting structure of such a resistance. The headphone is equipped with acoustic and/or electrical systems compensating the drop at the low frequencies, and there are no reflecting surfaces located close to the external ear of the user. The low frequencies drop may be compensated by passive or blind diaphragms, or the diaphragm of the electroacoustic transducer may be coupled to an air mass. A headset, including two headphones, may be designed for quadraphonic reproduction.

Abstract: The headphone preferably comprises a toroidal seal ring which rests against or surrounds the user's ear and is constituted of a soft, yielding, and preferably elastic material. The seal ring, with the headphone positioned on the head of a user, forms a coupling space between an active diaphragm, actuated by an electroacoustic transducer, and the auditory canal of the user's ear. This coupling space is substantially sealed from the exterior of the headphone, and is formed with at least one opening and preferably several openings each receiving a respective passive oscillatory diaphragm having a definite self-resonance. Each passive diaphragm is associated with a sound path leading therefrom to the open air, to the back side of the active transducer diaphragm, or to acoustically effective cavities. Respective acoustic frictional resistances are associated with each passive diaphragm. The arrangement of the passive diaphragms relative to the active transducer diaphragm may take various forms.

Abstract: An arrangement for headphones for converting frequency modulated audio oscillations into amplitude modulated oscillations, and particularly for rendering audible the vibrato of electronic musical instruments, such as electronic organs, includes a housing having an electroacoustic transducer therein with a diaphragm having a smooth frequency response zone which is connected to at least one mechanical transit-time member having a transit time from one end to the other not greater than 20 ms. The transit-time member is advantageously a helical spring which extends axially through the electroacoustic transducer or through a central ferromagnetic core thereof. The portion of the spring within the core is advantageously made of a thicker wire and of a smaller diameter than the remaining core so that it does not contact the walls thereof.