Abstract: In the audio signal reproducing apparatus, information on the transfer characteristics representative of the transfer characteristics from virtual sound sources to both ears of a listener in at least a first quadrant of the rotational angular position of the head M of the listener is stored in storing unit 22. The transfer characteristics in rotational angular position of the head M represented by detection outputs from detecting unit 5L, 5R and 13 for detecting the rotational angle position depending upon the movement of the head of the listener are formed based upon the transfer characteristics information of at least the first quadrant stored in the storing unit and left and right channel audio signals are processed by audio signal processing unit 23 for achieving a proper binaural reproduction relative to the virtual sound sources.

Abstract: An acoustic signal reproducing apparatus for supplying an acoustic signal to a headphone device, in which position-detecting reference signals from a reference signal source are sensed by a pair of signal sensors provided at two places over a listener's head. The turning angle and the relative distance of the head with respect to the reference signal source are calculated by processing units on the basis of these signal sensors and transmission characteristics with respect to an arbitrarily positioned imaginary sound source are found from the information concerning the relative distance and the turning angle, with the reference signal source as a reference position. Acoustic signals are processed by acoustic signal processing devices on the basis of the transmission characteristics to realize binaural reproduction with respect to the imaginary sound source.

Abstract: An earphone device includes an acoustic tube having an inner diameter substantially identical to that of the external auditory canal has an ear mounting portion at one end and an acoustic non-reflecting portion at the outer end. An earphone unit and an internal microphone unit are mounted on the periphery of the acoustic tube adjacent each other and communicate with the interior of the acoustic tube with their respective vibration plates facing inwardly of the tube. The phase of the signal representing the external noise in the acoustic tube picked up by the internal microphone unit is reversed and combined with the audio signal fed to the earphone unit.

Abstract: A hearing aid is disclosed in which the outside sound collected by a microphone is amplified and radiated from the earphone unit so as to be conducted to the user's external auditory meatus. The auditory tube is of an inside diameter approximately equal to that of the user's external auditory meatus and has one end arranged as a section for attachment to the user's auricle and the other end arranged as a reflectionless terminal. The earphone unit is mounted on the peripheral surface of the auditory tube with the sound radiating surface facing the inside of the tube.

Abstract: An acoustic signal reproducing apparatus for reproducing acoustic signals through headphone devices is disclosed. The left channel and right channel acoustic signals are provided by a device for processing the transmission characteristics with constant transmission characteristics representing the location of an imaginary sound source relative to both of the listener's ears. The left channel and right channel acoustic signals, processed in this manner by the device for processing the transmission characteristics, are provided by an acoustic signal processing device with a level difference and a time difference consistent with changes in orientation of the user's head. In this manner, optimum binaural reproduction with respect to the imaginary sound source may be achieved.

Abstract: In a speaker which comprises a diaphragm having a vibrating portion and an annular conductive portion, a current feeding coil facing the conductive portion with a predetermined gap therebetween, and a magnetic circuit including a top plate, a magnet and a yoke plate to which the current feeding coil is attached; the diaphragm is formed so that an electrical resistance of its conductive portion is lower than an electrical resistance of its vibrating portion.

Abstract: A sound reproducing apparatus is provided formed of an acoustic tube having first and second opposite ends, and having substantially a same inside diameter as that of an external acoustic meatus of the user who is wearing the sound reproducing apparatus. A loudspeaker unit is mounted to the acoustic tube intermediate the first and second ends such that a sound radiating surface thereof is directed to one side of the acoustic tube. The acoustic tube has at its first end an auricular attachment which is received at the external acoustic meatus. A second end is formed as a non-sound-reflecting end. The sound reproducing apparatus may also be adapted to have two loudspeaker units mounted to one or more acoustic tubes, respectively, and two auricular attachment sections may be provided, one for each ear. Left and right channel acoustical signals may be respectively input to the respective first and second loudspeaker units for stereo operation.

Abstract: A diaphragm using a metal material applied with anodic oxide films, in which said metal material contains one of lead compounds, inorganic metal compounds and phosphor compounds at least to a portion in the micropores of the anodic oxide film.