Abstract: A earphone for comfortably fitting into the ear to listen to a personal stereo. The earphone includes a housing adapted for inserting in to an ear of a person. A speaker is adapted for reproducing sound generated by a personal stereo. The speaker is operationally coupled to the personal stereo. The speaker is mounted within the housing. A plurality of bores through the housing are adapted for equalizing air pressure between the atmosphere and the ear of the user.

Abstract: A system and method for providing improved virtual sound images. One or more spatial cues of an audio signal may be modulated within a described range to increase the clarity and perceived localization of a virtual sound image. Interaural time delay, interaural intensity difference and/or spectra may be varied at below the “just noticeable level” to cause the virtual source location to move slightly relative to the listener's head. Such variation assists the listener's auditory system in filtering out ambiguous spatial cue information from the audio signal. The resulting virtual sound image has a larger sweet spot and is less sensitive to head movement.

Abstract: An apparatus and method for producing spatially distributed sound into a set of headphones having left and right ear-cups. An input receives a sound signal including a left channel signal, a right channel signal, a front channel signal and optionally a rear channel signal. The left and right are directly outputted by corresponding transducers in either the left or right ear-cup. The front and rear channels are each divided in two, so that they can be fed to transducers on both the left and right ear-cups. A set of headphones provided with such an apparatus is also provided.

Abstract: In the stereophonic sound field reproducing apparatus for reproducing a stereophonic sound field, at the time of using, a signal processing unit (4) executes a process on signals to reproduction-use minispeakers (6L1 through 6LN, 6R1 through 6RN) so as to simultaneously correct characteristics between the reproduction-use minispeakers (6L1 through 6LN, 6R1 through 6RN) and a head of a user (5) and characteristics between the reproduction-use minispeakers (6L1 through 6LN, 6R1 through 6RN), and the reproduction-use minispeakers (6L1 through 6LN, 6R1 through 6RN) arranged around the head of the user (5) input signals and output sound waves.

Abstract: A wireless headphone/speakers sound field control system, which includes a wireless signal receiver, a left speaker connected to the wireless signal receiver through a left differential amplifier and a left variable resistor, and a right speaker connected to the wireless signal receiver through a right differential amplifier and a right variable resistor, each of the left and right variable resistors being respectively connected to the positive pole of each of the left and right differential amplifiers, wherein a phase-shifting circuit is connected between the left differential amplifier and the right differential amplifier, having two sub-circuits each formed of a first capacitor, a variable resistor, a second capacitor and a resistor, each sub-circuit being connected in series between the right or left variable resistor and the left or right differential amplifier, the phase-shifting circuit enabling the differential amplifiers to have a dual signal input, so that left sound channel signal is inputted into

Abstract: Retractable speakers for use in a housing coupled to a computer, such as a portable computer or docking bar, which allow for sound quality optimization by being positionally adjustable relative to the computer housing. Retractable speaker locations relative to the computer housing include the top surface, side surfaces or front surface. Speakers are rotatable about a hinge relative to the housing surface, or emerge from the surface, such that the speaker is rotatable about an axis in order to direct the sound output toward a user. Alternatively, speakers disengage from the computer housing for placement on a surface in an optimum sound quality arrangement. Retracted speakers are substantially internal to the computer housing allowing for ease of transport and use in remote locations.

Abstract: A method and apparatus used for relieving motion sickness, wherein a sensor senses a motion of an object and a sensory converter coupled to the sensor and converts the sensed motion to corresponding sensory signals for presentation to a user. The sensory signals include audio signals, display signals, white noise signals, pink noise signals, brown noise signals, and audio tone signals The audio signals, white noise signals, pink noise signals, and brown noise sensory signals have a variation in spectral emphasis in proportion to the sensed motion, such as by varying a bandwidth, a center frequency, and an amplitude of a first range of the sensory signals. The display signals have a variation in a display characteristic and the audio tone signals have a variation in time intervals between successive audio tones. The audio tones may also include audio messages containing words.

Abstract: An apparent location of a sound source is controlled in azimuth and range to a listener of the sound using headphones by a range control block that has variable amplitude scalers and a time delay and by an azimuth control block that also has variable amplitude scalers and time delays. An input audio signal is fed in to the range control block and the values of the scalers and the taps on the delay buffers are read out of look-up tables in a controller that is addressed by an azimuth index value corresponding to any location on a circle surrounding the headphone wearer. Several range control blocks and azimuth control blocks can be provided depending on the number of input audio signals to be located. All of the range and azimuth control is provided by the range control blocks and azimuth control blocks so that the resultant signals require only a fixed number of filters regardless of the number of input audio signals to provide the signal processing.

Abstract: A system produces, based on samples of a single-channel input audio signal and an indication of a particular orientation of the listener relative to a source of the audio signal, a multi-channel output audio signal that emulates an audio signal as emanating from the source having the particular orientation to the listener. Interaural time delay (ITD) circuitry generates, from the single-channel input audio signal, a first left channel audio signal and a first right channel audio signal, wherein the first left channel audio signal and the first right channel audio signal are each based on the single-channel input audio signal but differ from each other at least with respect to phase based on the indication of the particular orientation. Azimuth frequency compensating (AFC) circuitry modifies the first left channel audio signal and the first right channel audio signal based on an azimuth, relative to the listener's left ear and right ear, respectively, of the particular orientation.

Abstract: First and second direct sound generator circuits 3a and 3b generate direct sound audio signals corresponding to a sound which travels from an imaginary sound source R and reaches directly to the user's ears. When distances from the imaginary sound source R to the left and right ears are different from each other, the generated audio signals are made to have a specified delay time between the first and second direct sound generator circuits 3a and 3b. First and second reflection sound generator circuits 4a and 4b generate reflection sound audio signals corresponding to a sound which travels from the imaginary sound source R and reaches the ears after being once reflected on the user's shoulder. The reflection sound audio signals are delayed by a specified delay time, respectively, from the corresponding direct sound audio signals.

Abstract: A system is disclosed for steering a monaural audio signal representing a source of sound into left and right audio signals for presentation to the corresponding ears of a listener so that the listener perceives the sound source in a specific location relative to his head. The left and right signals may be provided through headphones or loudspeakers, in the latter case employing techniques to cancel the crosstalk from each loudspeaker into the opposite ear of the listener. The monaural audio signal is filtered using head-related transfer functions (HRTFs) into the left and right outputs, these being equivalent to the acoustic HRTFs that would be generated if a source of sound were placed at the specific location relative to the listener.

Abstract: A head mounted surround sound virtual positioning system that includes a video recorder (200), which is operable to have disposed therein a tape (202), having a surround sound audio track associated therewith. The surround sound system is encoded on two channels, which are output to a Dolby.RTM. decoder (204), which is operable to extract the five surround sound system channels therefrom. The left front, left rear, right front and right rear channels are input to a virtual positioning system (264), which is operable to virtually position each of the speakers relative to the head of the listener (26). These signals are then combined with a combining circuit (268) to provide the virtual positioning of only two speaker lines (58) and (60), disposed adjacent the right and left ears of the listener (26). The speakers (58) and (60) are disposed on the head mounted system such that they are fixed relative to, the ear of the listener and slightly forward of the ears and adjacent the head.

Abstract: A method and apparatus for simulating the transmission of sound from sound sources to the ear canals of a listener encompasses novel head-related transfer functions (HTFs), novel methods of measuring and processing HTFs, and novel methods of changing or maintaining the directions of the sound sources as perceived by the listener. The measurement methods enable the measurement and construction of HTFs for which the time domain descriptions are surprisingly short, and for which the differences between listeners are surprisingly small. The novel HTFs can be exploited in any application concerning the simulation of sound transmission, measurement, simulation, or reproduction. The invention is particularly advantageous in the field of binaural synthesis, specifically, the creation, by means of two sound sources, of the perception in the listener of listening to sound generated by a multichannel sound system.

Abstract: A signal processing circuit for performing predetermined signal processes to input audio signals of four channels, headphones to which an output signal of the signal processing circuit is supplied, and detecting method for detecting a rotation of the head of the listener are provided. Digital filters for convoluting impulse responses obtained by converting head portion transfer functions from sound sources to the right and left ears into time regions to the input audio signals of four channels, time-difference adding circuits, and level-difference adding circuits are provided in the signal processing circuit. In the adding circuits, a time difference and a level difference of the signals which are transmitted through the adding circuits are controlled in accordance with detection outputs of the detecting method.

Abstract: A personal direction finding apparatus for determining the direction to be followed in order to reach a predetermined spot which includes a headset provided with two earphones and a circuit for generating a track error signal. The circuit includes a compass supported on the headset for outputting a heading signal corresponding to the heading of the direction of travel, a receiver for a position location and navigation system outputting a signal for the heading to be followed via one output, and a track error computing circuit.

Abstract: A sound image localization control device reproduces an acoustic signal on the basis of a plurality of simulated delay times and a plurality of simulated filtering characteristics as if a sound image ware located on an arbitrary position other than positions of separately arranged transducers. A convolver which is main device of the sound image localization control device comprise of a plurality of delay elements having the plurality of simulated delay times for delaying an audio signal to constitute a direct sound signal and a plurality of reflection sound signals. And the convolver includes a plurality of Infinite Impulse Response filters for filtering the direct sound signal and the plurality reflection sound signals on the basis of the plurality of simulated filtering characteristics respectively.

Abstract: A headphone apparatus includes a plurality of antennas for receiving an FM signal produced by FM-modulating a carrier signal with an audio signal, a plurality of tuning circuits for receiving reception signals of the plurality of antennas, a mixer circuit for causing tuning coils of the tuning circuits to be transformer-coupled to each other and for frequency-converting an output signal of one tuning circuit into an intermediate frequency signal, an FM demodulating circuit for FM-demodulating the intermediate frequency signal to produce the audio signal, and an acoustic unit for converting this audio signal into a sound. The directivity axes of the antennas are arranged perpendicularly thereby improving the reception of this headphone apparatus.

Abstract: A sound system has a receiver (204) for receiving individual decoded speaker signals comprised of three independent speaker signals (226) for driving associated speakers (208-214) disposed in predetermined relative positions about the listener. Head mounted speakers (58, 50) are fixed in position relative to the head (26) of the listener. A virtual positioning system (264) receives and then positions the three individual decoded signals (226) from the receiver (204) relative to the listener as virtually positioned speaker signals (266) representative of the predetermined relative positions of the associated speakers. The virtually positioned speaker signals (266) are transmitted proximate to the right and left ears (66, 68) of the listener through the right and left head mounted speakers (58, 60), but are actually perceived by the listener as being at the predetermined relative positions of the three independent speaker signals and their associated speakers (208-214).

Abstract: A speaker assembly for connecting an audio source to a microphone of a video recorder includes a housing having an exterior and a substantially hollow interior. An earphone assembly is provided having at least one speaker, with the at least one speaker located in the interior of the housing. Further, a video recording device is provided having a built-in audio source.

Abstract: A wearable speaker system which provides improved quality audio response and which does not interfere with the wearer's activities or block environmental sounds is disclosed. Transducer arrays, e.g. pairs of speakers, are situated in a wearable garment, headband, or the like and positioned on opposite sides of the wearer's head. In one embodiment, the transducer arrays share a common enclosure and are driven 180.degree. out of phase, so that back pressures cancel and low frequency response is enhanced. In another embodiment, two open-ended enclosures are provided, each with its own transducer array. In another embodiment, linear arrays of transducers are provided with appropriate time-delays between the audio signals. The speaker system is connected to or in communication with a conventional source of audio signals, such as a radio, tape player, CD player, cellular telephone or the like.