Abstract: A wireless audio system, including an audio and radio frequency module, that is prevented from being accidentally turned off by using an electronic gate responsive to a gate signal for coupling electrical power from a source to the module which bypasses the normal mechanical power switch. Means are provided for generating the gate signal in response to operation by the user so that the user cannot accidentally turn off the system by moving the power switch to its off position.

Abstract: A mounting for detachable securing a windscreen to a microphone includes a magnetic ring on one of the windscreen or microphone and a complementary steel ring on the other of the windscreen or microphone. A plastic ring is provided to hold the magnetic ring. The magnetic engagement between the magnetic ring and the steel ring will permit firm coupling of the windscreen and microphone in use. The mounting permits easy disengagement in the event the windscreen is not needed, or to permit maintenance or repair of the microphone. The plastic ring is retained on the microphone between the body and the head, which are interconnected by complementary threads on the exterior of the body/head and the interior of the other of the head/body.

Abstract: A microphone for use in a harsh environment of intense vibration and sound pressure. A microphone transducer and an acceleration transducer are located adjacent each other inside of a housing. The microphone transducer substantially blocks much of the acoustic signal from reaching the acceleration transducer. Accordingly, the acceleration transducer provides a signal substantially related only to the movement of the microphone, while the microphone transducer provides a signal related to both the movement of the microphone and the acoustic signal applied to it. The acceleration signal may then be removed from the microphone signal, providing a electrical signal substantially representative only of the acoustic signal.

Abstract: A diaphragm for microphones having a laminate structure which imparts damping characteristics to the diaphragm is disclosed. The laminate comprises upper and lower resilient layers composed of a plastic film. The upper and lower layers constrain a center layer composed of an elastomeric material having a high dissipation of vibratory shear motion. Manufacturing techniques for making such diaphragms are disclosed.

Abstract: A diaphragm for microphones having a laminate structure which imparts damping characteristics to the diaphragm is disclosed. The laminate comprises upper and lower resilient layers composed of a plastic film. The upper and lower layers constrain a center layer composed of an elastomeric material having a high dissipation of vibratory shear motion. Manufacturing techniques for making such diaphragms are disclosed.

Abstract: A construction for housing a microphone is disclosed. The construction is configured to improve the wind and noise protection for a small diameter microphone by providing a large diameter opening tapering to a smaller microphone aperture. The construction comprises a housing for a microphone transducer, and an adapter mateable with the transducer and housing. The adapter includes a plate having a greater diameter than the microphone aperture, and tapering to the smaller microphone diameter opening. In the preferred embodiments of the construction, a windscreen is included covering the tapered portion of the adapter.

Abstract: A microphone acoustical polar pattern converter conveniently converts the acoustical polar pattern of a microphone from cardioid to supercardioid and back at will. The converter includes primarily a body of a tubular body portion fitted forward of the microphone head. Most preferably, the body is formed of open pore plastic, with a pore size of 70 microns.

Abstract: A teleconferencing system for connection to telephone lines or other communication links. Directionally gated microphones receive local speech for audio send signal transmission to the far end on the telephone line, and audio receive signals from the far end are output locally via a loudspeaker. The outgoing send signals and incoming receive signals are automatically suppressed in accordance with user and setup controls (volume and suppression) and in accordance with the strength of the incoming receive signal. When the system is in a send mode, the receive signals are suppressed to a lower audible level; when the system is in a receive mode, the send signals are suppressed. The mode of the system is switched during conversation. When simultaneous talking (speech from both ends) occurs, priority is given to the interrupting party.

Abstract: A system for receiving a plurality of audio input signals encoded with sound directions drives a plurality of loudspeakers which are physically arranged to generate apparent sound images in relation to encoded sound directions. The encoded input signals are analyzed for determining whether one encoded sound direction exceeds a predominance threshold with respect to other encoded sound directions. Logic control signals are generated for indicating directionality of predominant sound directions. In response to generated logic signals, the directional stability of the apparent sound images is enhanced.

Abstract: A microphone and loudspeaker arrangement for use in a teleconference system, wherein a plurality of microphones are held in a fixed relationship to a loudspeaker. The microphones are independently gated ON in response to (1) speech picked up by the microphone, (2) a loudspeaker signal driving the loudspeaker and (3) an electrical signal related to the microphone signals of the other associated microphones. A noise adapting threshold circuit generates a voltage level representative of background noise which is compared with the microphone signal of a respective microphone for determining whether the microphone is receiving speech. A decisional circuitry monitors the microphone signal of the associated microphone with respect to a MAX bus which carries microphone signals representative of the level of microphone signals at the other microphones. The decisional circuitry generates a signal indicating that the associated microphone is the first loudest microphone signal.

Abstract: A speaker assembly is disclosed for use on a desk or tabletop, in conjunction with a telecommunication or teleconferencing system. The assembly includes a speaker supported above a generally conical and circular base having one or more acoustically reflective surfaces angled away from the speaker. A cover or cabinet is mounted around the rear of the speaker, and the speaker is attached to the assembly by a support plate mounted within the cover. The height of the interior of the cover is approximately the same as the height of the speaker. A plurality of bushings connect the support plate to the base. Sound exits from the assembly at substantially the level of the surface upon which the assembly rests. In the prefered embodiment, the conical base has a truncated upper portion, preferably formed as an inverted conical cavity coencentric with the circular base.

Abstract: An improved brush contact for a phonograph tone arm dynamic stabilizer. The contact includes bristles on a base, with free ends fanned in an arc. A portion of the bristles contact a record surface. Lateral movement of the tone arm across the record pivots the bristles and base, bringing new bristles into contact with the record surface.

Abstract: A shock-mounting apparatus designed for receiving and holding a microphone so as to isolate the microphone from surrounding structure-borne environmental vibration. The apparatus comprises a cradle that flexes when opening to receive the microphone and then closes firmly around the microphone body to hold it in place. The cradle also permits the microphone to be received into and removed from the shock-mounting apparatus without requiring disconnection from the signal output cable.

Abstract: A phonograph cartridge alignment gauge includes a plate, a cartridge work station and a visual indicator. A method of aligning a cartridge on a tone arm with the gauge, for stylus tangency at two radii, includes fastening the cartridge to the tone arm while the cartridge is on the work station and the turntable spindle is within a combination pivot point-spindle opening of the gauge, to establish stylus tangency at a first radii. The cartridge is refastened to the tone arm while the cartridge remains in the work station but after the tone arm is moved and the gauge pivoted about the combination opening, to establish stylus tangency at a second radii while maintaining tangency at the first. An alternate gauge and method include similar details.

Abstract: A phonograph stylus shank is formed by annealing and rolling beryllium sheet into a tube with an overlapping seam.