Abstract: In a short range radio communication headset, signals transmitted by the short range radio communications are received while direct sounds propagated from an external are detected. Then, a digital signal adaptation processing using either received signals or the direct sounds as reference signals are applied, and a ratio between the received signals and the direct sounds is controlled by correlating the reference signals and another one of the received signals and the direct sounds that are not used as the reference signals and extracting necessary components.

Abstract: The present invention provides an improved HRTF modeling technique for synthesizing HRTFs with varying degrees of smoothness and generalization. A plurality N of spatial characteristic function sets are regularized or smoothed before combination with corresponding Eigen filter functions, and summed to provide an HRTF (or HRIR) filter having improved smoothness in a continuous auditory space. A trade-off is allowed between accuracy in localization and smoothness by controlling the smoothness level of the regularizing models with a lambda factor. Improved smoothness in the HRTF filter allows the perception by the listener of a smoothly moving sound rendering free of annoying discontinuities creating clicks in the 3D sound.

Abstract: An audio user interface is provided in which items are represented in an audio field by corresponding synthesized sound sources from where sounds related to the items appear to emanate. At least some of the sound sources are associated in a collection as members of the collection; the collection itself has an associated collection-representing sound source. The collection can be changed in either direction between an un-collapsed state in which the member sound sources are present un-muted in the audio field, and a collapsed state in which the member sound sources are muted with the collection-representing sound source providing an audible presence for the collection in the audio field.

Abstract: The invention relates to a method of generating a left modified and a right modified audio signal for a stereo system from multichannel audio signals (XL, XR, XLS, XRS, and XC) with a left and a right channel and at least one further audio channel. According to the invention, the signal of the channel of highest energy is modified in a filter (1) with a transformation function in a first parallel branch (2) and is modified in a second filter (6) with a reverberation function in a second parallel branch (5), whereupon the modified signals are joined together in a summation unit (8).

Abstract: In an audio reproducing apparatus, first and second filters convolute impulse responses corresponding to transfer functions from a position where a right-hand sound source is located to the right and left ears of the listener into an audio signal, respectively, and third and fourth filters convolute impulse responses corresponding to transfer functions from a position where a left-hand sound source is located to the right and left ears of the listener into another audio signal, respectively. Fifth and sixth filters extract low-frequency components of the audio signal, and seventh and eighth filters extract low-frequency components of the another audio signal. The output signals of the first, third, fifth, and seventh filters are added, and the output signals of the second, fourth, the sixth, and eighth filters are added.

Abstract: Provided in accordance with the invention are a sound source identifying apparatus and method whereby objects as sound sources can be determined as to their locations with higher accuracy by using sound information and image information thereof and are separated from mixed sounds with certainty by using position information thereof. The sound source identifying apparatus (10) is constructed to include a sound collecting part; an imaging part; a sensing part; an image processing part; a sound processing part; and a control part.

Abstract: The disclosed embodiments relates to orienting a sound field in relation to a user and a generated set of images. For instance, a system may include a sound subsystem, a location subsystem, and a speaker subsystem. The speaker subsystem may include a plurality of sensors and a plurality of speakers. The sound subsystem may include a surround sound circuit that may be connected to a signal source and the speaker subsystem. The location subsystem may receive position information reflective of the orientation of a user and provide a signal that may be used by the sound circuit to adjust the audio signal based on the orientation of the user.

Abstract: A method for simulating an artificial sound environment including sending an ultrasound reference signal to a headphone assembly worn by a user having two ears, the headphone assembly audibly providing at least one audio signal to each of the ears, processing arrival times of the ultrasound reference signal at each ear, so as to measure a phase difference of the signal as perceived by one ear in contrast to the other ear, modulating at least two audio signals, at least one signal for each ear, in accordance with the phase difference, and sending the at least two audio signals via the headphone assembly to each of the ears.

Abstract: An audio processing apparatus that includes a first filter for converting n-channel (n?1, positive integer) audio signals input from at least one signal source into two-channel signals, a pair of second filters to which two-channel output signals from the first filter means are input and which have transfer functions that are not correlated, and an output unit for supplying a pair of output signals from the pair of second filters to left and right loudspeaker units of a headphone device.

Abstract: A method and apparatus for producing virtual sound sources that are externally perceived and positioned at any orientation in azimuth and elevation from a listener is described. In this system, a set of speakers is mounted in a location near the temple of a listener's head, such for example, on an eyeglass frame or inside a helmet, rather than in earphones. A head tracking system determines the location and orientation of the listener's head and provides the measurements to a computer which processes audio signals, from a audio source, in conjunction with a head related transfer function (HRTF) filter to produce spatialized audio. The HRTF filter maintains the virtual location of the audio signals/sound, thus allowing the listener to change locations and head orientation without degradation of the audio signal. The audio system of the present invention produces virtual sound sources that are externally perceived and positioned at any desired orientation in azimuth and elevation from the listener.

Abstract: Device and method for controlling the perceived distances of sound sources by manipulating vocal effort and presentation level of a synthetic voice. Key components are a means of producing speech signals at different levels of vocal effort, a processor capable of selecting the appropriate level of vocal effort to produce a speech signal, and a carefully calibrated audio system capable of accurately matching the RMS power of the signals reaching the listener's left and right eardrums to the power that would occur for a sound source 1 m directly in front of the listener in an anechoic environment.

Abstract: Surround-effect, providing no unnatural feeling to the listeners who sit next to each other under side-by-side basis through virtual sound sources, is realized. A surround left channel signal SL and a surround right channel signal SR are mixed with an adder 10 and are in monaural. A first monophonic signal and a second monophonic signal thus resulted are supplied to a virtual localization processor 12. A first virtual localization output of the processor 12 is supplied to a front left speaker SPL and a front right speaker SPR and a second virtual localization output thereof is supplied to a front center speaker SPC. In this way, virtual sound sources can be created at the right and the left to the listener 2. Similarly, virtual sound sources can also be created at the right and the left to the listener 3. Sound fields from the virtual surround sources are in reverse to the listener 2 and the listener 3.

Abstract: An audio signal processing device to enable accurate calculation of angles and displacements and to enable reduction of circuit scales includes a digital signal processing circuit (31) that performs virtual acoustic image localization processing such that an acoustic image is localized at an arbitrary position in the vicinity of the listener by reproducing, using headphones (2) or a plurality of speakers, output signals obtained by signal processing input audio signals, and is characterized in that analog detection signals from a sensor (1) that detects the state of action of the listener are input to the digital signal processing circuit (31) via an A/D converter (30), and the transmission characteristics of these audio signals are modified in realtime, according to values derived by processing the values of analog detection signals from the sensor (1) or by processing the analog detection signals.

Abstract: A headphone system includes a headphone; and a signal processing circuit for outputting an acoustic signal to the headphone. The headphone includes a first speaker and a third speaker for a right ear of a listener, a second speaker and a fourth speaker for a left ear of the listener, and a support for supporting the first through fourth speakers so that the first and second speakers are located forward with respect to a vertical plane including a straight line connecting the hole of the right ear and the hole of the left ear of the listener, the second and fourth speakers are located rearward with respect to the vertical plane, and the first through fourth speakers are out of contact with the right ear and the left ear of the listener.

Abstract: An audio processing apparatus has a converter for converting n-channel (positive integral number: n?1) audio signals input from at least one sound source into two-channel signals, a pair of correcting filters to which a pair of two-channel signals converted by converter are supplied and which correct a difference of the sense of hearing due to a difference of headphone characteristics, and an output section for supplying a pair of output signals from the pair of correcting filters to right and left speaker units of a headphone.

Abstract: The present invention disclosed and claimed herein, in one aspect thereof, comprises a method for enhancing the front sound image during reproduction in a listening space of a stereo sound program, comprising the steps of receiving left and right channels of the stereo sound program; generating a virtual center channel signal from the left and right channels of the stereo sound program; and driving a center channel speaker with the virtual center channel signal, the center channel speaker disposed at a central location in a front portion of the listening space.

Abstract: The invention relates to a method of interacting with an acoustic modal structure of a room, the method including

Abstract: A system for generating at least one remote virtual speaker location in connection with at least a partial reflective environment (12, 12, 14 or 15) in combination with an audio speaker for creating multiple sound effects including a virtual sound source from the reflective environment which is perceived by a listener (53) as an original sound source, by generating a primary direct audio output by emitting audio compression waves toward a listener, and generating a secondary indirect audio output from at least one virtual speaker (24, 25 or 26) remote from the audio speakers, by emitting ultrasonic sound from at least one parametric speaker (20, 21 or 22) associated with the audio speakers and oriented toward at least one reflective environment which is remote from the audio speakers

Abstract: The sound reproduction system is of the kind which comprises electro-acoustic transducer means, and transducer drive means for driving the electro-acoustic transducer means in response to a plurality of channels of a sound recording. The electro-acoustic transducer means comprises sound emitters which are spaced-apart in use, the transducer drive means comprising filter means that has been designed and configured with the aim of reproducing at a listener location an approximation to the local sound field that would be present at the listener's ears in recording space, taking into account the characteristics and intended positioning of the sound emitters relative to the ears of the listener, and also taking into account the head related transfer functions of the listener.

Abstract: A sound imaging system, which by processing left and right stereo channel audio signals of a conventional two channel stereo system, distributes signals to a speaker array of a number of speakers determined by a listening area. Listeners located in different places within the listening area, can have an audible perception of an equivalent distribution to that of the conventional two channel stereo system. Additionally they will have an audible central perception of the centered program material equivalent to that obtained from the conventional two channel stereo system when the listeners are located in a median plane of the conventional two channel stereo system speakers.

Abstract: A sound reproduction system includes headphones (11). The headphones include structures for generating sound (4, 5) and microphones (6, 7). Further, the system includes filters (8,9) for filtering a signal such that the sound produced simulates external sound sources. The system includes a feed-back and control system (10) in which signals (rl(k), rr(k)) from the microphones (6, 7) are used to set the settings WXL(k), WXR(k) of the filters (8,9).

Abstract: A storage unit stores data representative of one or several sound sources and a listener of said sound sources. These data comprise position data corresponding to respective positions of the sound sources and the listener. An interface is provided for enabling a user to select the listener or a sound source and to control a change in the position data corresponding to the selected listener or sound source. A constraint solver means changes, in response to the position data change controlled by the user, at least some of the position data corresponding to the element(s), among the listener and the sound sources, other than said selected listener or sound source, in accordance with predetermined constraints. The system further comprises a command generator for delivering control data exploitable by a music spatialisation unit as a function of the position data corresponding to the sound sources and the listener.

Abstract: Disclosed is a method designed to stimulate the presence of one or more sound sources in virtual positions in three-dimensional space, in the perception of a listener occupying a real physical space, by means of suitable drive loudspeakers whose position is not perceived by the said listener, and a device for the implementation of the said method.

Abstract: Multi-channel headphones capable of providing quality 3-dimensional (3-D) sound in an atmosphere of intimacy and privacy for individuals is provided. The multi-channel headphones ensure high-quality 3-D sound reproduction with accurate phase using distinct speaker units for multiple channels. The multi-channel headphones includes at least two speaker units for each ear piece, each for generating distinct sounds from multiple channels; and at least two enclosures in each of which each of the at least two speaker units arc installed. The multi-channel headphones include a sound guide portion in each of the enclosures to guide the sound emanating from the corresponding speaker unit into the listener's ear. A diffraction effect of the sound from the rear speaker can be induced.

Abstract: The disclosure relates to localization of an acoustic image out of the head in hearing a reproduced sound via headphone, and includes the steps of: with audio signals S1-S11 of left, right channels reproduced by an appropriate audio appliances as input signals, branching the input signals of the left and right channels to at least two systems; to form signals of each systems corresponding to the left, right channels with left, right speaker sounds imagined in an appropriate sound space with respect to the head of a listener wearing a headphone Hp and virtual reflected sound in the virtual sound space SS caused from a sound generated from the left and the right virtual speaker SPL, SPR, creating a virtual speaker sound signal by processing so that the virtual speaker sounds from the left and the right speakers are expressed by direct sound signals, and virtual reflected sound signals by processing so that the virtual reflected sound is expressed by reflected sound signals; mixing the direct sound signal and re

Abstract: Original head-related transfer functions (HRTFs) are modified for a non-standard dimensioned head. The HRTF includes a near-ear response function, a far-ear response function, and an inter-aural time delay (ITD). The modified HRTF resembles an HRTF approximating that derived for a listener having different head and/or ear dimensions to the standard dimensions. The ITD value of the HRTF is multiplied by a given scaling factor independent of frequency. The near ear and/or far ear response function of the HRTF is multiplied by a constant scaling factor in the frequency domain independent of time delay, to expand or compress the functions in the frequency domain. The near ear and/or far ear response function of the HRTF are provided with a positive or negative offset value in the frequency domain. The amplitude of the near ear and/or far ear response function of the original HRTF(s) is (are) multiplied by a given gain factor.

Abstract: A method of customizing the HRTF for each tested individual for providing all tested individuals an optimum audio experience by providing convincing and realistic three-dimensional sounds. Customization can be achieved by playing a series of sample sounds and having the tested individual locate where the sound is emanating from. In this way, the method can identify for each test subject which audible positional cues are most important, how frequency changes are interpreted as position, and what effects are most convincing and pleasurable. This information is used to effect the HRTF for each tested individual. The customized HRTF will then be applied to all three-dimensional sounds giving the listener an optimum audio experience.

Abstract: A method of simulating a spatial sound environment to a listener over headphones is disclosed comprising inputting a series of sound signals having spatial components; determining a current orientation of the headphones around the listener; determining a mapping function from a series of spatially static virtual speakers placed around the listener to each ear of the listener; utilising the current orientation to determine a current panning of the sound signals to the series of virtual speakers so as to produce a panned sound input signal for each of the virtual speakers; utilising the mapping function to map the panned sound input signal to each ear of the listener, and combining the mapped panned sound input signals to produce a left and right output signal for the headphones.

Abstract: In views of a disadvantage that in a conventional method for localization of sound image in stereo listening, the amount of software is increased and the scale of hardware is enlarged, this invention has been achieved to solve such a problem and intends to provide a processing method for audio signal to be inputted from an appropriate sound source capable of higher precision localization of sound image than the conventional method. When a sound generated from an appropriate sound source SS is processed as an audio signal in the order of inputs on time series, the inputted audio signal is transformed into audio signals for the left and right ears of a person and further each of the audio signals is divided to at least two frequency bands.

Abstract: A loudspeaker unit has, in combination, a pistonically driven diaphragm loudspeaker and a generally planar resonant panel loudspeaker, in which the plane of the resonant panel lies in the same orientation as an axis along which the diaphragm is pistonically driven. The resonant panel loudspeaker may be located behind the diaphragm loudspeaker, with the resonant panel loudspeaker functioning as a diffuse dipole, e.g. to generate surround sound reproduction, and the diaphragm loudspeaker located in the null of the dipole and functioning as an acoustic monopole, e.g. to generate imaged stereophonic sound reproduction.

Abstract: A multichannel audio system for radiating sound to a listening area that includes a plurality of listening spaces. The audio system includes directional audio devices, positioned in a first of the listening spaces, close to a head of a listener, for radiating first sound waves corresponding to components of one of the channels and nondirectional audio devices, positioned inside the listening area and outside the listening space, distant from the listening space, for radiating sound waves corresponding to components of a second of the channels.

Abstract: A method of processing a series of input audio signals representing a series of virtual audio sound sources placed at predetermined positions around a listener to produce a reduced set of audio output signals for playback over speaker devices placed around a listener, the method comprising the steps of: (a) for each of the input audio signals and for each of the audio output signals: (i) convolving the input audio signals with an initial head portion of a corresponding impulse response mapping substantially the initial sound and early reflections for an impulse response of a corresponding virtual audio source to a corresponding speaker device so as to form a series of initial responses; (b) for each of the input audio signals and for each of the audio output signals: (i) forming a combined mix from the audio input signals; and (ii) forming a combined convolution tail from the tails of the corresponding impulse responses; (iii) convolving the combined mix with the combined convolution tail to form a combined t

Abstract: A method of synthesizing an approximate impulse response function from a measured first impulse response function in a given sound field includes: sampling an early part of the impulse response for the given sound field; synthesizing a part impulse response which approximates to the sampled part of the given impulse response by curve fitting using a plurality of basis functions provided by respective multi-tap FIR filters, said part impulse response including scattering artefacts; synthesizing subsequent further part impulse responses using the same filters; applying an envelope function which decreases the amplitude with increasing time, and constructing an extended approximate impulse response by combining successive part impulse responses with irregular overlap to minimize audible artifacts. The synthesized impulse response function has psycho-acoustic properties similar to those of the original impulse response function, and enables fewer taps to be employed.

Abstract: The invention relates to a method of reproducing multichannel audio sound via several real and at least one virtual speaker (2, 3, 4, 5, 6, 9, and 10). According to the invention, the audio sound envisaged for a real speaker (2, 3, 4, 5, and 6) is reproduced partly via the real speaker (2, 3, 4, 5, and 6) and partly via a virtual speaker (9 and 10) positioned in the same location.

Abstract: An acoustic signal reproduction device includes a reproduction speaker and a signal processing section for generating an acoustic signal for causing a listener to recognize a reference speaker. The signal processing section includes a compensation data input section for receiving compensation data from the outside of the acoustic signal reproduction device and a calculation section for calculating the acoustic signal based on the audio signal and the compensation data and outputting the acoustic signal to the reproduction speaker. The compensation data has a value H/C, where H is a transfer function from the reference speaker to a control point located in the vicinity of an ear of the listener, and C is a transfer function from the reproduction speaker to the control point located in the vicinity of the ear of the listener.

Abstract: A new approach to capturing and reproducing either live or recorded three-dimensional sound is described. Called MTB for “Motion-Tracked Binaural,” the method employs several microphones, a head tracker, and special signal-processing procedures to combine the signals picked up by the microphones. MTB achieves a high degree of realism by effectively placing the listener's ears in the space where the sounds are occurring, moving the virtual ears in synchrony with the listener's head motions. MTB also provides a universal format for recording spatial sound.

Abstract: A sound imaging system, which by processing left and right stereo channel audio signals of a conventional two channel stereo system, distributes signals to a speaker array of a number of speakers determined by a listening area. Listeners located in different places within the listening area, can have an audible perception of an equivalent distribution to that of the conventional two channel stereo system. Additionally they will have an audible central perception of the centered program material equivalent to that obtained from the conventional two channel stereo system when the listeners are located in a median plane of the conventional two channel stereo system speakers.

Abstract: A method for creating a multichannel audio signal that provides the impression of spatial sound is disclosed, the method comprising providing an expected multichannel audio output signal having spatialised soundfield components; perturbing the spatial components; and utilising the perturbed spatial components to determine the multichannel audio signal. The perturbations can be substantially in accordance with the expected head movements of listeners of the audio signal and can be derived from a group of listeners to the audio signal. The expected head movements also preferable include an added substantially random movement.

Abstract: A system and method are described for rendering a left rear surround input signal at a left rear virtual speaker location and rendering a right rear surround input signal at a right rear virtual speaker location. The method includes phase shifting the left rear surround input signal by a first phase shift. The right rear surround input signal is phase shifted by a second phase shift. The phase shifted left rear surround input signal is phase shifted using an HRTF selected to render the left rear surround input signal at the left rear virtual speaker location. The phase shifted right rear surround input signal is transformed using an HRTF selected to render the right rear surround input signal at the right rear virtual speaker location.

Abstract: An earpiece device (300) provides automatic left/right ear sensing for stereo reception as well as the ability to receive two separate and distinct channel signals. The earpiece device (300) provides an orientation indication as to which ear or channel it is coupled. A pair of such devices can be used as stereo headphones providing interchangeability between ears. The devices can also be used to receive distinct and separate channel signals. Thus, a communication system can automatically adjust a transmission to the headphone device in response to the orientation of the earpieces with minimal effort on the part of the user.

Abstract: To provide a sound image control system able to concurrently perform sound image localization control for two persons. The present invention is directed to a sound image control system controlling a sound image localization position by reproducing an audio signal from a plurality of loudspeakers. The sound image control system includes at least four loudspeakers for reproducing the audio signal and a signal processing section. The signal processing section sets four points corresponding to both ears of two listeners as control points, and performs signal processing for the audio signal input into the plurality of loudspeakers so that two target sound source positions indicating sound image localization positions of the respective two listeners are set in the same direction with respect to the two listeners. Here, the two target sound source positions are set so as to satisfy a following condition, T1<T2≦T3<T4.

Abstract: The beginning detection, accommodation and frequency bias properties of the human hearing mechanism have been modeled to create systems that can detect directional transients (“sound events”) in a sound field and separately localize them. These models break down a sound field into sound events and non-sound events and separately localize the sound events and non-sound events. Sound events are generally identified according to the frequency bias and beginning detection properties. Once detected, sound events are generally localized according to differential steering angles (steering angles to which the steady-state signals have been accommodated) or ordinary steering angles and which reflect the direction of a sound event indicated in its rise-time. When no sound events are detected, non-sound events are localized according to a steering angle that does not reflect rapid motion.

Abstract: An acoustic image localization signal processing device capable of localizing an acoustic image in an arbitrary direction by means of a simple configuration includes: a sound source data storage unit 1, which stores second sound source data obtained by subjecting first sound source data to signal preprocessing in advance such that the acoustic image is localized in a predetermined direction; and, an acoustic image localization characteristic application processing unit 2, which applies an acoustic image localization position characteristic, based on position information from an acoustic image control input unit 4, to the second sound source data, when the second sound source data are read from the sound source data storage unit 1 and reproduced by headphones 7R, 7L. Accordingly, the acoustic image localization position of the reproduced output signals D1, D2 resulting from the second sound source data is controlled.

Abstract: A hearing device has a transfer function adjustable by a set of parameters. The hearing device can have two microphones, a processing unit, and a speaker unit. A direction identification unit is operationally connected to the processing unit. Communication between a user of the hearing device and at least one reference person is ensured for changing positions of the user and/or the reference person. The transfer function is adjusted as a function of at least one current reference person direction by changing the set of parameters. The reference person direction encloses an angle with a reference plane of the user.

Abstract: Sound Space Replication is a multichannel audio system optimization and management system. The replication begins by mapping and storing volumetric acoustic topological data of the primary (audio creation) venue's sound system in situ, associated with the completion of an audio program material. Prior to playback, the secondary (audio listening) venue's sound system is similarly mapped in situ. The secondary data is compared to the primary data, with discrepancies articulated as corrections data. The corrections data applied to the secondary audio system include wave shaping, phase, spatial repositioning, miss-configured and phantom channel replacement, etc. The secondary audio system sound space is thus optimized as directly referenced to the primary audio system sound space.

Abstract: A sound reproducing device comprising: a signal processing device including a first signal processing circuit supplied with an input audio signal of at least one channel to convert the input audio signal to a 2-channel audio signal with which an acoustic image is located at a predetermined position when the input audio signal is reproduced substantially by a 2-channel speaker device, and a second signal processing circuit supplied with the 2-channel audio signal to subject the 2-channel audio signal to signal processing which is equivalent to a transfer function from said 2-channel speaker device to both the ears of a listener, thereby converting and outputting the input audio signal to a 2-channel audio signal; and at least one earphone device including a pair of electro-acoustic transducer supplied with the 2-channel audio signal from the second signal processing circuit, and detector for detecting the movement of the head of the listener, wherein the second signal processing circuit performs the processing

Abstract: A method of processing a plural channel audio signal representing a three dimensional sound-field for generation by respective left and right loudspeakers arranged at a given distance from a listener, including: a) choosing a distance between said loudspeakers and said listener; b) determining from this chosen distance an optimal amount of transaural acoustic crosstalk compensation, the optimal amount being a function of the chosen distance; and c) applying said optimal amount of crosstalk compensation to said left and right channels. The optimal transaural crosstalk cancellation is preferably achieved using a near ear response transfer function and a far ear response transfer function which asymptotically approach different values at low frequencies. The method may further include choosing an angle between the left channel loudspeaker and the right channel loudspeaker, and determining from both the chosen angle and the chosen distance an optimal amount of transaural crosstalk compensation.

Abstract: A sound reproduction system comprises headphones (11). Said headphones comprise means for generating sound (4, 5) and microphones (6, 7)(i.e. means for recording sound). Further the system comprises filter means (8,9) to filter a signal such that the sound produced simulates external sound sources. The system comprises a feed-back and control system (10) in which a signal (rl(k), rr(k)) from the microphone (6, 7) is used to set the settings WXL(k), WXR(k) of the filter means (8,9).

Abstract: A sound reproducing device including a signal processing device including a first signal processing circuit supplied with an input audio signal of at least one channel to convert the input audio signal to a 2-channel audio signal with which an acoustic image is located at a predetermined position when the input audio signal is reproduced substantially by a 2-channel speaker system, and a second signal processing circuit supplied with the 2-channel audio signal to subject the 2-channel audio signal to signal processing which is equivalent to a transfer function of the 2-channel speaker system to both the ears of a listener, thereby converting and outputting the input audio signal to a 2-channel audio signal.

Abstract: Herein disclosed is an audio signal adjusting apparatus for respectively adjusting a plurality of raw audio signals to produce a plurality of adjusted audio signals, comprising: audio signal adjusting means for respectively adjusting said raw audio signals to produce said adjusted audio signals, and to be operably connected with a plurality of loudspeakers for respectively producing a plurality of audio sounds in a specific sound space, said audio sounds being respectively indicative of said adjusted audio signals, and collectively originated from at least one imaginary sound source having a width, said imaginary sound source being imagined to produce said audio sounds at a location spaced apart from each of said loudspeakers; location control signal producing means for producing a location control signal indicative of said location of said imaginary sound source; controlling means for controlling said audio signal adjusting means to allow each of said raw audio signals to be adjusted by said audio signal adj