Abstract: A method of processing a single channel audio signal to provide an audio source signal having left and right channels corresponding to a sound source at a given direction in space, includes performing a binaural synthesis introducing a time delay between the channels corresponding to the inter-aural time difference for a signal coming from said given direction, and controlling the left ear signal magnitude and the right ear signal magnitude to be at respective values. These values are determined by choosing a position for the sound source relative to the position of the head of a listener in use, calculating the distance from the chosen position of the sound source to respective ears of the listener, and determining the corresponding left ear signal magnitude and right ear signal magnitude using the inverse square law dependence of sound intensity with distance to provide cues for perception of the distance of said sound source in use.

Abstract: A method and apparatus for processing multi-channel audio signals in which the channels are processed by one of alternatively selectable processes to produce an alternatively selectable number of output channels, the process being responsive to information contained in the input signal.

Abstract: A circuit is provided for controlling a minimum operating voltage of an integrated control circuit of a switching power supply. The circuit includes at least one switch for switching the minimum operating voltage from a first voltage value to a second voltage value under conditions of low or null load of the switching power supply, and for switching the minimum operating voltage from the second voltage value to the first voltage value if the load of the switching power supply is greater than a predetermined load and the supply voltage is greater than the first voltage value. The minimum operating voltage can assume at least the first voltage value and the second voltage value, and the first voltage value is greater than the second voltage value. Also provided is a method for controlling a minimum operating voltage of an integrated control circuit of a switching power supply.

Abstract: The invention is directed to a sound system with four loudspeakers and at least one signal processing device connected to the input of two loudspeakers and controlled by two input signals. The signal processing device produces control signals for the loudspeakers. The respective control signals are equal to the sum of the input signals which are weighted differently with respect to amplitude and phase, so that the radiation characteristic of the two loudspeakers depends on the weighting of the input signals.

Abstract: The invention relates to a system for generating sounds with a left front loudspeaker which converts an electric signal of a left audio channel and with a right front loudspeaker which converts an electric signal of a right audio channel. Such a system for generating sounds in a room is known. The electric signals are processed such that spatial rear loudspeakers are dispensed with and the front loudspeakers generate a surround or spatial sound. According to the invention, a virtual filter generates virtual sound bodies laterally of a listener in a region between 80 and 100 degrees. Experiments have shown that the human ear is most sensitive to surrounding sound when sound sources are arranged laterally of a listener's head or when spatial sound is generated laterally of a listener.

Abstract: A three-dimensional sound reproducing apparatus is configured by cascading a sound field effect adding unit and a crosstalk canceling unit. The sound field effect adding unit adds a predetermined three-dimensional sound field effect to an input audio signal, thereby generating audio signals respectively corresponding to left and right channels. The crosstalk canceling unit performs a calculation process on the audio signals of the two channels so that, when the audio signals are respectively generated by two loudspeakers positioned in front of a listener, the audio signals reach the left and right ears of the listener without producing crosstalk. The resulting audio signals are supplied to the loudspeakers, respectively.

Abstract: A three-dimensional sound reproducing apparatus is configured by cascading a sound field effect adding unit and a crosstalk canceling unit. The sound field effect adding unit adds a predetermined three-dimensional sound field effect to an input audio signal, thereby generating audio signals respectively corresponding to left and right channels. The crosstalk canceling unit performs a calculation process on the audio signals of the two channels so that, when the audio signals are respectively generated by two loudspeakers positioned in front of a listener, the audio signals reach the left and right ears of the listener without producing crosstalk. The resulting audio signals are supplied to the loudspeakers, respectively.

Abstract: A process for enhancing ambience in an audio signal output that is derived from an audio signal input in a dual channel audio ambience extraction circuit. The process includes cross-coupling of audio signals in one channel with audio signals in another channel. Each of the cross-coupled signals is attenuated and delayed by an adjustable time period that is within a haas delay time and is then applied in the feedback path to a summing input of an opposite channel. At the summing input, the signals are mixed with subsequent audio signal inputs to that channel. All of the attenuated and delayed signals are continuously applied to outputs of the extraction circuit during the cross-coupling process. The output signals comprise the original signals plus delayed and attenuated reproductions of the original signal along with continuing signals that are submitted to the extraction circuit subsequent to the initial signals.

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: An audio signal encoding apparatus includes a device for compressing multiple-channel digital audio signals into compression-resultant multiple-channel signals respectively. The multiple-channel digital audio signals relate to a sampling frequency and a quantization bit number. The compression-resultant multiple-channel signals, a signal representative of the sampling frequency, and a signal representative of the quantization bit number are formatted into a formatting-resultant signal. The formatting-resultant signal contains a sub packet and a sync information portion. The sub packet contains at least portions of the compression-resultant multiple-channel signals. The sync information portion contains the signal representative of the sampling frequency and the signal representative of the quantization bit number.

Abstract: A first selector switch outputs a second audio signal of m channel corresponding to a selected second zone to a power amplifier of the m channel and a second selector switch couples output of the power amplifier of the m channel to a speaker terminal for the selected second zone whereby an audio signal can be supplied to either one of a plurality of second zones. In one aspect of the invention, a first selector switch outputs a second audio signal of m channel corresponding to a selected second zone to a power amplifier of the m channel determined by a control section and a second selector switch couples output of the m channel determined by the control section to a speaker terminal for the selected second zone whereby an audio signal can be supplied to one or more zones among plural second zones.

Abstract: The inventive mechanism uses several sub-systems to generate outputs from the stereo input signal. A first sub-system synthesizes the phantom center output, which places the monaural center image between the left and right speakers in front of the listener. A second sub-system synthesizes the virtual surround (or rear) output signals, which places the sound images to the sides of the listener. A third sub-system synthesizes the left and right stereo outputs, and expands the locations of the left and right sound images.

Abstract: A stereo sound circuit device for providing three-dimensional surrounding effect has a difference circuit for acquiring difference signal of a left channel sound and a right channel sound. The stereo sound circuit device further provides a filter circuit consisting of a first and a second filtering operation units for applying a first and second filtering functions to the difference signal output from the difference circuit for generating a three-dimensional surrounding sound signal. The first filtering function implements a band pass filter with a central frequency of about 7.23 KHz. The second filtering function implements a band pass filter with a central frequency of about 318 Hz. A signal level adjust circuit is provided for adjusting the signal level of the sound signal output from the filter circuit. A mixer is provided for combining the adjusted three-dimensional surrounding sound with the original left channel sound and right channel sound.

Abstract: This invention provides a system capable of transitioning from surround sound effect to stereo sound effect, and then to a monophonic sound effect using front speakers. A user may control the amount of surround sound effect that is combined with stereo sound effect, and the amount of stereo sound effect that is combined with monophonic sound effect. The user may also control the system to hear pure surround sound effect, stereo sound effect, or monophonic sound effect. The system may allow a user to control the contribution of a particular sound effect by controlling the relative proportions of the filtered dipole signals and the attenuated unfiltered dipole signals. The signal processing may be also done through an analog device. The system may also process some audio channels in an inverted form and compensate for these inversions by reversing the polarity of that output to the speaker, as well as accept two-channel and four-channel audio inputs.

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: An integrated individual listening device and decoder for receiving an audio signal including a decoder for decoding the audio signal by separating the audio signal into a voice signal and a background signal, a first end-user adjustable amplifier coupled to the voice signal and amplifying the voice signal; a second end-user adjustable amplifier coupled to the background signal and amplifying the background signal; a summing amplifier coupled to outputs of said first and second end-user adjustable amplifiers and outputting a total audio signal, said total signal being coupled to an individual listening device.

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: Processing a single channel audio signal provides a plurality of audio channel signals by separating the single channel audio signal into a first separated signal, characterized by a spectral pattern generally characteristic of speech, and a second separated signal processed to provide the remainder of the plurality of audio output channel signals.

Abstract: The present invention provides a method to convert the conventional two-channel uncoded audio system into multichannel system. There is no coding/decoding procedure in the invention, but just process the phases of the original two audio channels to provide different audio sources for surrounding distribution and achieve the best effect of reproducing the original audios. The present invention also provides an audio processor for implementing the method.

Abstract: Techniques of making a recording of or transmitting a sound field from either multiple monaural or directional sound signals that reproduce through multiple discrete loud speakers a sound field with spatial harmonics that substantially exactly match those of the original sound field. Monaural sound sources are positioned during mastering to use contributions of all speaker channels in order to preserve the spatial harmonics. If a particular arrangement of speakers is different than what is assumed during mastering, the speaker signals are rematrixed at the home, theater or other sound reproduction location so that the spatial harmonics of the sound field reproduced by the different speaker arrangement match those of the original sound field. An alternative includes recording or transmitting directional microphone signals, or their spatial harmonic components, and then matrixing these signals at the sound reproduction location in a manner that takes into account the specific speaker arrangement.

Abstract: A method and audio converter for generating further audio signals (u, ul, ur, uc, us) from initial audio signal (x, xl, xr), wherein optionally an information signal (in means 23) is derived from said initial audio signals (x). On basis of the initial audio signal (x, xr, xl), a dominant signal y(k) and a residue signal (or signals) q(k), substantially transverse to each other, are determined (means 21 and 22). In at least two frequency ranges frequency components of the dominant signal are analysed (means 24), and a difference signal yr ({y(k)?yb(k)) corresponding to the dominant signal minus a frequency range component of the dominant signal in one or more frequency ranges (yb(k)) is formed. The difference audio signal yr and the residue signal q(k) are transformed into said further audio signal u(means 25), i.e. u = T ? ( y r ? ( k ) q ? ( k ) ) .

Abstract: A vehicle audio system has an audio central unit to which one or more further audio components are connected via an associated first data bus, and are interfaced for data communication between the first data bus and a second data bus of another type in the vehicle. One of the audio components is an audio gateway unit which contains the interface, and is an independent component separate from the audio central unit. In addition to the data bus gateway functions, the audio gateway unit includes further standard audio functions spanning vehicle types or countries, or further audio functions which are implemented so as to be parameterizable according to specific vehicle type and/or country.

Abstract: A surround-sound circuit has a delay time memory (31) for storing a digital audio input signal IN, and outputs the stored input signal as a surround-sound signal a predetermined time later. The input signal is compressed by a compressor (32) in the form of ADPCM encoder before it is stored in the memory (31), and the compressed signal retrieved from the memory is expanded by an expander (33) in the form of ADPCM decoder before it is added to the input signal. The invention may reduce appreciably the amount of data to be stored in the memory, and hence the storage capacity of the RAM, without directly loping the audio input signal IN and hence avoiding appreciable deterioration of the signal IN.

Abstract: A three-dimensional sound reproducing apparatus is configured by cascading a sound field effect adding unit and a crosstalk canceling unit. The sound field effect adding unit adds a predetermined three-dimensional sound field effect to an input audio signal, thereby generating audio signals respectively corresponding to left and right channels. The crosstalk canceling unit performs a calculation process on the audio signals of the two channels so that, when the audio signals are respectively generated by two loudspeakers positioned in front of a listener, the audio signals reach the left and right ears of the listener without producing crosstalk. The resulting audio signals are supplied to the loudspeakers, respectively.

Abstract: An audio rendering system and method are disclosed. The audio rendering system generally comprises front and rear signal modifiers configured to receive a plurality of audio signals representing a plurality of sources of aural information and location information representing apparent location for the source of said aural information. A gain is applied to the signals representative of the location information. A front signal modifier includes a plurality of head-related transfer functions filters and a rear signal modifier includes a plurality of filters configured to approximate head-related transfer function filters. The system further includes front speakers comprising a left front speaker and right front speaker configured to receive signals from the front signal modifier and generate a signal to a listener. At least one rear speaker is configured to receive signals from the rear signal modifier and generate a signal to the listener to offset frontward bias created by the front speakers.

Abstract: A system for determining speaker spatialization parameters. The system includes a graphical interface allowing a user to select a number of listeners, number of speakers, and a listening space and for graphically displaying on a display device the one or more listeners and one or more speakers within the listening space. The system further includes a speaker spatialization module for determining one or more speaker spatialization parameters based upon the relative positions on the display device of the one or more listeners and the one or more speakers within the listening space system. The user may reposition the speakers and for each speaker that is repositioned the speaker spatialization module recalculates the speaker spatialization parameters for that speaker. The user may also graphically reposition one of the listeners and the speaker spatialization module recalculates all of the speaker spatialization parameters for all of the speakers.

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

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: 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: 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 circuit for processing multichannel audio signals, comprises a frequency characteristics correction device and an output device. The frequency characteristics correction device corrects frequency characteristics of an audio signal of a channel including an audio signal component having a predetermined frequency band, of audio signals of a multichannel comprising at least a right channel and a left channel, in accordance with correction characteristics determined based on a head related transfer function. The output device mixes the audio signal component having the frequency characteristics corrected with an audio signal of the right channel and an audio signal of the left channel to generate mixed output audio signals, and outputting the mixed output audio signals as a right channel output audio signal and a left channel output audio signal.

Abstract: Sound recordings are played through a closely-spaced pair of loudspeakers with a predetermined listener position having an included angle of between 6° and 20°, and filter means being employed in creating said sound recordings, the filter means having characteristics such that when the sound recordings are played, the need to provide a virtual imaging filter means at the inputs to the loudspeakers to create virtual sound sources is avoided, the sound recording being such that when played through the loudspeakers a phase difference between vibrations of the two loudspeakers results where the phase difference varies with frequency from low frequencies where the vibrations are substantially out of phase to high frequencies where the vibrations are in phase, the lowest frequency at which the vibrations are in phase being determined approximately by a ringing frequency, f0.

Abstract: Systems and techniques for controlling a surround sound system having multiple input signals and multiple spatially diverse transducers may include defining a first control region and a second control region. When operating in the first control region, a first set of functions is performed. For example, for each of the spatially diverse transducers, an input signal may be selected, a relative strength of the selected input signal may be adjusted, and the adjusted input signal may be applied to the transducer. When operating in the second control region, a second set of functions is performed. For example, for each of the spatially diverse transducers, two or more input signals may be selected, a relative strength of the selected input signals may be adjusted, the adjusted input signals may be mixed, and the mixed input signals may be applied to the transducer.

Abstract: The invention generally relates to a method and apparatus for taking an input signal, replicating it a number of times and modifying each of the replicas before routing them to respective output transducers such that a desired sound field is created. This sound field may comprise a directed beam, focussed beam or a simulated origin. In a first aspect, delays are added to sound channels to remove the effects of different travelling distances. In a second aspect, a delay is added to a video signal to account for the delays added to the sound channels. In a third aspect, different window functions are applied to each channel to give improved flexibility of use. In a fourth aspect, a smaller extent of transducers is used top output high frequencies than are used to output low frequencies. An array having a larger density of transducers near the centre is also provided. In a fifth aspect, a line of elongate transducers is provided to give good directivity in a plane.

Abstract: The invention relates to a method for converting signals in two-channel stereo format to become suitable to be played back using headphones. The invention also relates to a signal processing device for carrying out said method. According to the invention left direct path (Ld) and left cross-talk path (LX) signals are formed from the left input signal (Lin), and correspondingly right direct path (Rd) and right cross-talk path (RX) signals are formed from the right input signal (Rin), and further the left output signal (Lout) is formed by combining said left direct-path (Ld) and said right cross-talk path (Rx) signals, and correspondingly, the right output signal (Rout) is formed by combining said right direct-path (Rd) and said left cross-talk path (Lx) signals.

Abstract: A data processing apparatus is designed for simulating an acoustic characteristic of an acoustic space which contains a sound source for generating a sound and a sound receiving point for receiving the sound. In the apparatus, each of a plurality of characteristic control sections processes sound data and outputs the processed sound data. The characteristic control sections correspond to transmission paths which must exist in the acoustic space such that the sound generated from the sound source travels to the sound receiving point through the respective transmission paths. An instruction section provides a processing instruction of the sound data to each characteristic control section such that each characteristic control section processes the sound data according to the provided processing instruction to thereby execute the simulation of the sound traveling through the corresponding transmission path.

Abstract: A surround reproducing circuit includes a first adder for generating a difference signal of an L signal and an R signal which are inputted, a low-pass filter connected to an output side of the first adder, and second and third adders for mixing an output signal of the low-pass filter as a surround signal with the L signal and the R signal in an opposite phase relationship to each other. Change in a phase is lessened within a frequency band of 20 Hz to 20 KHz and the localization can become definite, and furthermore, a harsh high pass is also lessened. Consequently, it is possible to realize a surround effect having natural spread. Furthermore, the number of capacitors to be required can also be decreased.

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: A method of down mixing a plurality of signals including at least a left surround signal, a right surround signal, a left signal and a right signal into a stereophonic pair that is a left transmitted signal and a right transmitted signal includes summing the left surround and right surround signals to provide a monophonic surround signal, filtering the monophonic surround signal to provide a filtered monophonic signal having properties related to the diffraction pattern around the head of a listener, multiplying the filtered monophonic surround signal with a right coefficient signal related to the ratio of the magnitude of the right surround signal to the sum of the magnitudes of the left surround signal and the right surround signal to provide a left product signal and multiplying the filtered monophonic surround signal with a left coefficient signal related to the ratio of the magnitude of the left surround signal to the sum of the magnitudes of the left surround signal and the right surround signal to prov

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: In a first mode where no audio reproduction is to be executed in a second zone, each selector switch shifts to a Z1 contact. In a second mode where audio reproduction is to be executed in the second zone, each selector switch shifts to a Z2 contact. In the second mode, a DSP executes sound field correction on main and rear signals such that sound fields in the first zone have desired characteristics. Setting section can select either a first speaker mode where speakers connected to first output terminals and speakers connected to second output terminals are both positioned in the first zone, or a second speaker mode where the speakers connected to the first output terminals are positioned in the first zone and the speakers connected to the second output terminals are positioned in the second zone. When the output to the first output terminals is off while the output to the second output terminals is on in the second speaker mode, the DSP stops outputting the surround signals.

Abstract: A process for translating M audio input channels representing a soundfield to N audio output channels representing the same soundfield, wherein each channel is a single audio stream representing audio arriving from a direction, M and N are positive whole integers, and M is at least 2, generates one or more sets of output channels, each set having one or more output channels. Each set is associated with two or more spatially adjacent input channels and each output channel in a set is generated by a process that includes determining a measure of the correlation of the two or more input channels and the level interrelationships of the two or more input channels.

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: Surround sound encoding and decoding includes apparatus and techniques for encoding a number of major channels of a surround sound signal, such as left, right, center, left surround and right surround, into a lesser number of channels, such as left transmitted and right transmitted, and decoding the lesser number of channels into a larger number of decoded channels, such as left, right, center, left surround and right surround, for being electroacoustically transduced.

Abstract: A method for realizing virtual multi-channel by spectrum analysis is disclosed. The low-frequency-effect sound data is obtained by averaging sound data of left and right channels in the two-channel sound source and filtering the average by a first low pass filter. The central channel sound data is obtained by averaging sound data of the left and the right channels in the two-channel sound source and filtering the average by a second low pass filter. The surround right and left sound data is obtained by copying sound data of the left and the right channels in the two-channel sound source, respectively.

Abstract: A sound reproduction system has been developed, for converting signals on two input channels into surround signals on five or seven output channels and vice-versa. A decoder is included which enhances the correlated component of the input signals in the desired direction and reduces the strength of such signals in channels not associated with the encoded direction, while preserving the apparent loudness of all output channels, the separation between the respective left and right output channels and the total energy of the uncorrelated component of the input channels in each output channel. Included within the decoder is a uniquely defined matrix that helps to ensure that the surface of the output signals is smooth and continuous. An encoder is also included which encodes five or seven channels of sound into two so the two channels may be decoded by a variety of decoders with the correct sound direction and level.

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: A car-borne sound system that reproduces a recorded multi-channel music source in the 5. 1 system or the like system into a natural sound environment in a room of an automobile. Conventionally, at a driver's seat or at a front passenger seat, a sound image of vocal sounds (singing voice) was locating deviated from the natural placement. The present sound system eliminates such unnatural sound image positioning. A front center signal and a front right and a front left signals, which include much of the vocal components, are added on to a rear right and a rear left signals so that rear speakers (106 and 107) also reproduce the vocal components. Thus the vocal sound image is placed and fixed in the central place to provide a natural listening environment.

Abstract: The data put to the digital filter operation and the data not put to the digital filter operation are synthesized together at a predetermined distribution ratio to form a stereophonic sound image. A digital filter operation is executed for forming a sound image in the vertical direction that reaches one ear being diffracted by the head, and a digital filter operation is executed for forming a sound image in the vertical direction in the other ear, thereby to form a stereophonic sound image in the vertical direction. Of the sound generated from one of the different sound systems, the sound reaching one ear is canceled and the only sound reaching the other ear is validated by generating a counterbalance sound component. Excess sound component is erased, the excess sound component being generated from the other sound system and being not desired for forming the stereophonic sound image.