Abstract: A single loudspeaker has a substantially single-point source of sound energy derived from multiple drivers to provide a surround sound effect. The surround sound is effective for listeners close to the single loudspeaker or substantially distant within a room. The physical size of the loudspeaker is convenient for placement on top of a computer monitor or television set. The single loudspeaker produces a dynamically variable energy gradient between the listener's right and left ears and the perception of sound emanating from changing locations in the space surrounding the loudspeaker. The placement of a plurality of these loudspeakers surrounding the expected listener location allows the coverage of larger spaces with separate dynamically variable energy gradient pairs.

Abstract: The generation of skewed hypercardioid sound energy fields (in polar diagrams) from right front and left front "surround" loudspeakers with the principal nulls directed at the expected listener location produces the effect of sidewall and rearwall loudspeakers in a home theater setting without any actual sidewall or rearwall loudspeakers. The effect is enhanced by secondary nulls that are directed so as to "reflect" off the front wall of the room toward the expected listener location. Each surround loudspeaker contains an antiphase driver and circuitry including a delay network that powers the drivers to create the skewed hypercardioid sound energy field. The invention is independent of electrical mixing and interaction of two or more input channels. Rather the channels are assumed to be independent and the invention concerns the unique directional sound energy radiation pattern generated from each channel considered independently.

Abstract: New loudspeaker driver configurations comprise positioning the high frequency driver between symmetrically located lower frequency drivers and providing in combination electrical or acoustical delay to the high frequency driver relative to the lower frequency drivers. The lower frequency drivers are located above and below at equal distances from the high frequency driver or, with more than two lower frequency drivers, symmetrically about the high frequency driver. The sound pressure level and phase response is substantially equivalent to co-axial drivers including suitable high frequency electric delay circuitry operating at similar power levels. The delay for the high frequency driver is electrical or electrical in combination with a geometrical delay. With a stereo pair of loudspeakers the high frequency driver may be offset from the vertical between the above and below low frequency drivers in an outboard direction of the stereo pair.

Abstract: Disclosed is a passive delay network for insertion in the high frequency signal path of a crossover network in a high fidelity loudspeaker. The delay network provides means to adjust the optimum listening window electrically rather than by changes in the physical construction of the speaker cabinet. Electroacoustic high frequency and low frequency drivers may be mounted in a planar baffle or mounted co-axially. The delay network retains a "flat" amplitude-frequency characteristic and minimizes time dispersion in the acoustic signal received by the listener. Correction for time delay is most important near the transition frequency of the crossover network because near the transition frequency substantially equal sound energy is radiated by both the high frequency and low frequency drivers.Also disclosed is a novel construction for a co-axial driver combination and a technique for adjusting both the delay in the electric delay line network and the air path delay of electroacoustic drivers.

Abstract: A dihedral loudspeaker for use in mirror image stereophonic loudspeaker systems combines a pair of coaxial drivers with variable dispersion circuits and a high frequency delay network. The variable dispersion circuits decrease the amplitude of the electric signal to the indirect or ambient firing coaxial drivers relative to the direct firing drivers. Each coaxial driver combination comprises a high frequency driver in front of a low or mid-range frequency driver. The pair of coaxial driver combinations in each loudspeaker are substantially identical and each is effectively almost a point source of sound energy. The pair of coaxial drivers are located in dihedral baffles of the loudspeaker approximately the interaural distance apart. The variable dispersion circuits allow the loudspeakers to be adjusted such that listeners outside of the area between and in front of the loudspeakers hear an illusion of the sound image coming from the space between the loudspeakers.

Abstract: A dihedral loudspeaker for use in mirror image stereophonic loudspeaker systems combines a pair of coaxial drivers with variable dispersion circuits and a high frequency delay network. The variable dispersion circuits decrease the amplitude of the electric signal to the indirect or ambient firing coaxial drivers relative to the direct firing drivers. Each coaxial driver combination comprises a high frequency driver in front of a low or mid-range frequency driver. The pair of coaxial driver combinations in each loudspeaker are substantially identical and each is effectively almost a point source of sound energy. The pair of coaxial drivers are located in dihedral baffles of the loudspeaker approximately the interaural distance apart. The variable dispersion circuits allow the loudspeakers to be adjusted such that listeners outside of the area between and in front of the loudspeakers hear an illusion of the sound image coming from the space between the loudspeakers.

Abstract: Electric circuitry to correct for spurious sound pressure responses of audio transducers is disclosed. In particular, electric circuitry to compensate for "pre-shoot" of an audio transducer system is disclosed. The circuitry includes a delay line electric circuit carrying the bulk of the electric signal energy to the audio transducers and a parallel circuit to feed forward in real time an electric signal replica of diminished amplitude to the audio transducers. The replica thereby cancels or greatly minimizes the "pre-shoot" or prior undesired significant sound pressure responses of the audio transducers. The circuits include, in combination with the feed forward circuit, additional circuitry to counteract subsequent undesired significant sound pressure amplitude responses such as resonance (ringing). The new circuits utilize series resonant circuits in parallel to ground with the audio transducers as the preferred means to counteract the subsequent undesired sound pressure responses.

Abstract: Disclosed is a passive delay network for insertion in the high frequency signal path of a crossover network in a high fidelity loudspeaker. The delay network provides means to adjust the optimum listening window electrically rather than by changes in the physical construction of the speaker cabinet. Electro-acoustic high frequency and low frequency drivers may be mounted in a planar baffle or mounted co-axially. The delay network retains a "flat" amplitude-frequency characteristic and minimizes time dispersion in the acoustic signal received by the listener. Correction for time delay is most important near the transition frequency of the crossover network because near the transition frequency substantially equal sound energy is radiated by both the high frequency and low frequency drivers.Also disclosed is a novel construction for a co-axial driver combination and a technique for adjusting both the delay in the electric delay line network and the air path delay of electroacoustic drivers.

Abstract: The invention comprises improved electroacoustic audio speaker cross-over networks. The improvements comprise both the addition of various passive elements and a novel inductively coupled circuit configuration. The improvements are applied to low pass and high pass networks and combinations thereof. In the preferred embodiments a separate electrical circuit is inductively coupled to the filter network. The physical configuration of the separate circuit can be easily adjusted to counter variations in individual speaker performance parameters. Thus, production variations in speakers from the same manufacturer or among the products of different manufacturers can be overcome and a better matching of speakers provided.In the simplest embodiment the separate inductively coupled circuit comprises a copper ring placed within an inductive coil of the filter. Adjustment is accomplished by adjusting the physical location within the coil or by small changes in the physical dimensions of the ring.