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Bob Carver Patents

Robert W. Carver has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

Wall mounted speaker system, apparatus and method

Patent number: 7844068

Abstract: A wall mounted speaker system that is arranged to alleviate problems of unwanted noise in the production and transmission of audio waves, particularly in the lower wave lengths from 20 to 200 Hz. There is a speaker unit having a pair of vertically spaced speakers, and an inertial noise suppressing section positioned between the two speakers. The inertial noise suppressing section has an inertial mass which is moved in a back and forth motion to create an inertial offsetting force into a housing structure of the speaker section. The two speakers also create inertial forces which are also transmitted into the housing of the speaker unit, and these are substantially diminished by the interaction of the inertial forces of the speakers and those of the inertial noise suppressing system.

Type: Grant

Filed: January 4, 2006

Date of Patent: November 30, 2010

Assignee: Linear Corporation

High back-EMF high pressure subwoofer having small volume cabinet
low frequency cutoff and pressure resistant surround

Patent number: 6566960

Abstract: A subwoofer cabinet having a volume less than 1 ft3; axially aligned openings in opposed cabinet walls; first and second cages mounted on respective ones of the walls in alignment with the openings; a voice coil driven driver including an annular 225 oz. magnet affixed to the first cage; a stationary pole piece extending through the magnet and defining a magnetic gap therebetween; a voice coil mounted on a cylindrical voice coil former positioned within the gap; a cone affixed to one end of the former; a first flexible surround secured to the outer end of the cone and attached at its periphery to the first cage; a flexible spider secured to the former and at its outer periphery to the first cage; a drive amplifier capable of delivering 2,700 watts to a nominal 4-ohm resistive load and swinging 104 volts for delivering (+)&Dgr;v and (−)&Dgr;v drive signals to the voice coil for driving the voice coil driven driver through a peak-to-peak stroke of about 2.

Type: Grant

Filed: May 12, 1999

Date of Patent: May 20, 2003

 

High back EMF, high pressure subwoofer having small volume cabinet,
low frequency cutoff and pressure resistant surround

Patent number: 6418231

Abstract: A subwoofer cabinet having a volume less than 1 ft axially aligned openings in opposed cabinet walls; first and second cages mounted on respective ones of the walls in alignment with the openings; a voice coil driven driver including an annular 225 oz. magnet affixed to the first cage; a stationary pole piece extending through the magnet and defining a magnetic gap therebetween; a voice coil mounted on a cylindrical voice coil former positioned within the gap; a cone affixed to one end of the former; a first flexible surround secured to the outer end of the cone and attached at its periphery to the first cage; a flexible spider secured to the former and at its outer periphery to the first cage; a mass driven driver including a 1.7 lb. mass; a second flexible surround secured to the mass and to the second cage; a flexible spider attached to the second cage and to the mass; both surrounds having a uniform thickness of at least 0.1″, an edge roll having a diameter of at least 1.

Type: Grant

Filed: August 9, 1999

Date of Patent: July 9, 2002

Integrated audio amplifier

Patent number: 6373335

Abstract: An audio amplifier comprising a power amplifier section, a power supply, and a control circuit. The power supply is made up of a positive and negative power supply section, with the positive supply section and the negative supply section delivering, respectively, positive and negative power inputs through the power amplifier section. Each power supply section comprises a transformer and a switch section to supply current pulses to the primary winding of the transformer. A filter circuit component is connected to an output of each secondary winding. The control circuit controls the strength of the current pulses of the power supply sections in accordance with the strength of the audio signal.

Type: Grant

Filed: September 11, 2000

Date of Patent: April 16, 2002

Compact speaker system

Publication number: 20010031060

Abstract: Disclosed is a compact speaker system in which each speaker unit includes a folded ribbon loudspeaker that is mounted on the forward face of the speaker unit housing. Mounted on each side of the speaker housing is a woofer with the region in which the woofers are mounted being sealed and of relatively small volume. Each woofer is constructed to allow relatively long voice coil excursion and hence, high sound output levels. In addition, the woofers are constructed to withstand box pressure substantially greater than 0.2 lbs/in2 that is created within the sealed portion of the speaker housing when the woofers are being driven at high output levels. Signal processing circuitry is included for processing each channel of multi-channel audio programming such as surround sound. The signal processing arrangements of the invention include circuit stages to control channel gain over the low frequency range, the mid-frequency range and the high frequency range.

Type: Application

Filed: January 8, 2001

Publication date: October 18, 2001

Subwoofer with active and passive drivers

Publication number: 20010024509

Abstract: A woofer apparatus having a cabinet defining a chamber, a magnet, a voice coil member positioned to reciprocate in the magnetic field of the magnet, a speaker diaphragm, and a passive radiator diaphragm. The components are arranged so that the maximum box pressure during maximum displacement mode of operation is greater than 0.2 psi. the tuned frequency of the apparatus is, in a preferred mode, at about 35 Hz, so that the passive radiator has substantially greater maximum excursion strokes at maximum displacement than the speaker diaphragm.

Type: Application

Filed: January 8, 2001

Publication date: September 27, 2001​

Integrated audio amplifier

Patent number: 6166605

Abstract: An audio amplifier having an amplifier section and a power supply. The power supply comprises a positive power supply section and a negative power supply section, each of which provides voltage to the positive and negative power inputs to the amplifier. The control circuitry for the power supply sections causes the voltage output from the power supply sections to vary in accordance with the amplitude of the audio signal so that the power supply voltages track the positive and negative components of the audio signal so that the supply voltages are at a predetermined level above and below the positive and negative components of the audio signal, respectively. Each of the power supply sections has a pair of switches that open and close alternately to transmit power pulses to opposite ends of the primary winding, and the secondary winding in turn transmit power pulses alternately through a filter component to its respective input of the amplifier section.

Type: Grant

Filed: September 18, 1998

Date of Patent: December 26, 2000

High back-EMF, high pressure subwoofer having small volume cabinet,
low frequency cutoff and pressure resistant surround

Patent number: 6130954

Abstract: A small, compact subwoofer cabinet; openings in two cabinet walls; first and second cages mounted on respective ones of the walls in alignment with the openings; a voice coil driven driver including an annular magnet weighing approximately 225 oz affixed to the first cage; a stationary pole piece extending through the magnet and defining a magnetic gap therebetween; a voice coil mounted on a cylindrical voice coil former positioned within the gap; a cone affixed to one end of the former; a first flexible surround secured to the outer end of the cone and to the first cage; a flexible spider secured to the former and to the first cage; a mass driven driver including a mass aggregating about 2 lbs; a second flexible surround secured to the mass and to the second cage; a flexible spider attached to the second cage and to the mass; both surrounds having a thickness of about 0.1", an edgeroll having a diameter of about 1.5", and capable of standing off internal pressures of up to about 3 lbs/in.sup.

Type: Grant

Filed: July 26, 1999

Date of Patent: October 10, 2000​

Audio amplifier with tracking power supply utilizing inductive power converters

Patent number: 6104248

Abstract: Disclosed is an audio amplifier with a tracking power supply that uses inductive power converters to provide positive and negative amplifier operating potentials of a magnitude that exceeds the DC voltage available to power the amplifier. The tracking power supply includes both a positive-going tracking-up converter and a negative-going tracking-up converter. Each of the tracking-up converters include an inductor, a capacitor, a diode, and a pulse-width modulator. The pulse-width modulator of the positive-going tracking-up converter produces signals representative of the positive amplitude of the audio signal being amplified and the pulse-width modulator of the negative-going tracking-up converter produces signals representative of the negative amplitude of the signal being amplified.

Type: Grant

Filed: March 31, 1999

Date of Patent: August 15, 2000

High back EMF, high pressure subwoofer having small volume cabinet,
low frequency cutoff and pressure resistant surround

Patent number: 5937074

Abstract: A small, compact subwoofer cabinet; openings in two cabinet walls; first and second cages mounted on respective ones of the walls in alignment with the openings; a voice coil driven driver including an annular magnet weighing approximately 225 oz. affixed to the first cage; a stationary pole piece extending through the magnet and defining a magnetic gap therebetween; a voice coil mounted on a cylindrical voice coil former positioned within the gap; a cone affixed to one end of the former; a first flexible surround secured to the outer end of the cone and to the first cage; a flexible spider secured to the former and to the first cage; a mass driven driver including a mass aggregating about 2 lbs.; a second flexible surround secured to the mass and to the second cage; a flexible spider attached to the second cage and to the mass; both surrounds having a thickness of about 0.1", an edgeroll having a diameter of about 1.5", and capable of standing off internal pressures up to about 3 lbs./in.sup.

Type: Grant

Filed: August 12, 1997

Date of Patent: August 10, 1999

High power audio subwoofer

Patent number: 5748753

Abstract: A subwoofer including a walled cabinet defining an enclosed space of less than 1 cubic foot; axial openings formed in two opposed cabinet walls; and, two driver assemblies mounted within the cabinet on a common axis with the wall openings.

Type: Grant

Filed: January 2, 1996

Date of Patent: May 5, 1998

Apparatus for receiving and processing frequency-modulated electromagnetic signals

Patent number: 5204904

Abstract: A system for increasing the quality of the sound available from a broadcast, frequency modulated, radio frequency, stereophonic signal. Sound quality is promoted by: (1) so switching between available antennas that the signal available from the antenna receiving the incoming signal which is stronger and contains the least multipath distortion is processed into audio output signals, and (2) at least partially blending stereophonically related audio input signals into a monophonic signal if the modulation of the incoming first and second audio signals decreases below a selected threshold value and if: (a) the multipath distortion in the incoming signal reaches or exceeds a preselected threshold value, or (b) the strength of the incoming signal decreases to, or falls below, an also preselected threshold value.

Type: Grant

Filed: December 1, 1986

Date of Patent: April 20, 1993

Assignee: Carver Corporation

Inventors: Robert W. Carver, Victor O. Richardson

Apparatus and methods for enhancing a video display

Patent number: 4916538

Abstract: A video processor for generating an improved video display by synthesizing high-frequency components of a received video signal in a manner that the frequencies of the synthesized high-frequency components are greater than the upper-frequency limit of the received video signal. A selected higher frequency band of the received signal modulates a continuous wave signal having a selected frequency so that the upper sideband frequency components of the modulated output are greater than the video signal upper-frequency limit. The lower sideband components of the modulated output are removed and the upper sideband components are then added in phase with the original video signal to generate a composite signal having a greater bandwidth than the original received signal for generating the improved video display.

Type: Grant

Filed: February 6, 1987

Date of Patent: April 10, 1990

Assignee: Carver Corporation

Inventors: Robert W. Carver, Montgomery F. Ross

Apparatus and methods for removing unwanted components from a communications signal

Patent number: 4815141

Abstract: A tuner includes circuitry for conditioning an audio signal including (i) a pilot signal canceller, (ii) a noise limiter, (iii) a notch filter, and (iv) a de-emphasizer; as well as an attenuator for RF signals. In an exemplary embodiment, an AM stereo pilot signal canceller utilizes a 25 Hz signal which is added or subtracted from the left and right channels to eliminate the pilot signal. The noise limiter includes a capacitor which is switched into the feedback circuit of an operational amplifier when the input is at a selected level. The diverting of the feedback signal to the capacitor causes the amplifier to saturate thereby removing the noise from the signal. The notch filter includes first and second band pass filters which are centered at a selected frequency, e.g. 10 kHz, for removing a 10 kHz beat note. The passed band is phase shifted so that it is 180 degrees out of phase with the original signal and then added back with the original signal to remove the selected band.

Type: Grant

Filed: December 2, 1986

Date of Patent: March 21, 1989

Assignee: Carver Corporation

Inventors: Robert W. Carver, Victor O. Richardson

Lightweight, high-power audio amplifier and power supply

Patent number: 4808946

Abstract: An audio amplifier and power supply having a power transformer with power supply and control means to provide pulses of electrical energy at a substantially constant supply voltage, with the duration of the pulses being dependent upon a value that is related to the demands of the amplifier. The transformer charges a power capacitor to a substantially constant voltage to supply power for the amplifier. The frequency range of the pulses is between about 400 to 2,000 cycles per second, with a frequency being at about 1,100 cycles per second in a preferred embodiment.

Type: Grant

Filed: December 22, 1986

Date of Patent: February 28, 1989

Inventors: Robert W. Carver, M. Robert McKinley

Loudspeaker diaphragm mounting system and method

Patent number: 4803733

Abstract: A loudspeaker diaphragm mounting system where there is a perimeter frame to which is mounted a planar flexible diaphragm having electrically conductive elements thereon. The frame has two perimeter sections that have matching perimeter grooves to receive an elongate tensioning member which presses the edge portion of the diaphragm into at least one of the grooves. By controlling the force with which the two frame sections are pushed together, tension on the diaphragm can be controlled.

Type: Grant

Filed: December 16, 1986

Date of Patent: February 7, 1989

Inventors: Robert W. Carver, James J. Croft​

Dimensional sound recording and apparatus and method for producing the same

Patent number: 4603429

Abstract: A sound recording having right and left information channels to drive right and left speakers, respectively. The right information channel has a left main stereo component having a pattern corresponding and similar to a left stereo input signal. In addition, it has a right to left compensating component having a pattern which corresponds to an inverted and delayed pattern of a right stereo input signal. In like manner, the right channel has a right main stereo component having a pattern corresponding and similar to the right stereo input signal. It also has a left to right compensating component having a pattern which corresponds to an inverted and delayed pattern of the left stereo input signal. The effect is that the main stereo components travelling to the nearest ear of a listener are not diminished substantially, while the main stereo components travelling to the further ear are diminished. The effect is a highly dimentionalized sound pattern.

Type: Grant

Filed: October 6, 1981

Date of Patent: July 29, 1986

Audio amplifying apparatus and method

Patent number: 4586002

Abstract: An audio amplifier operatively connected to the secondary winding of a power transformer. The primary winding of the transformer is connected through a control circuit which has switch means that is turned on and off during selected portions of half cycles of the voltage imposed upon the primary winding of the transformer. By turning the switch on and off at appropriate intervals, the proper amounts of electrical energy can be delivered to supply the power requirements for amplification, while substantially reducing problems of idling currents in the primary winding of the transformer. Thus, the transformer can be made much smaller than in power supplies of conventional amplifiers.

Type: Grant

Filed: June 1, 1984

Date of Patent: April 29, 1986

High efficiency, light weight audio amplifier and power supply

Patent number: 4484150

Abstract: The present invention comprises an amplifier circuit (2, 1100, 1500, 1600) and transformer based power supply (24, 500, 700, 1710) wherein greater efficiency is achieved by using the input signal characteristics to control various aspects of the circuit operation. The transformer primary winding (8, 500a, 700a, 1710a) is energized by a pulsed power supply (6, 502, 702, 1702) which is duty cycle modulated in response to the signal being amplified. One embodiment of the amplifier employs output transistors (Q1101, Q1103, Q1105, Q1107, Q1109, Q1111) connected to respective stepped voltage levels. Amplifier control circuitry (1126, 1130, 1138, 1140) acts in relation to the input signal amplitude to more evenly distribute the voltage drop across the interconnected transistors (Q1101, Q1103, Q1105, Q1107, Q1111), thus reducing amplifier power requirements and minimizing distortion in the amplifier output.

Type: Grant

Filed: September 1, 1982

Date of Patent: November 20, 1984

FM Stereo apparatus and method

Patent number: 4457012

Abstract: An output matrix adapted to receive an L+R signal component (made up of the sum of L and R stereo components) and an L-R signal component, and to combine these in a manner to produce a separate L output and a separate R output, with certain modifications to the outputs. The higher frequency portion of the L-R signal is passed through a detector which, in turn, causes a leading edge amplifier to transmit to the matrix only those signal portions where there is a relatively abrupt change of amplitude, these being the signal portions that contain the main stereo information which gives the directional information. Also, the L+R signal component, in addition to being transmitted directly to the matrix, is directed through time delay means to produce a time delayed L+R signal component that is also transmitted to the matrix, so as to provide what is called "ambient" to the output of the matrix.

Type: Grant

Filed: June 3, 1982

Date of Patent: June 26, 1984

Audio amplifier

Patent number: 4445095

Abstract: An audio amplifier connected to the secondary winding of a transformer. The primary winding of the transformer is connected in a series with a triac to a conventional power source, such as a 60 hertz, 115 to 120-volt source of alternating current. The triac is turned on at a predetermined time during the latter portion of each half cycle to cause a current pulse to be transmitted through the primary winding. To make the triac non-conductive to terminate each pulse, there is provided a bypass circuit (comprising a second triac and a capacitor in series) connected in parallel with the first triac. A tank circuit is connected in parallel with the transformer primary to cause an oscillation in the primary winding, so that the second triac can be turned on at a time of low current to shunt the first triac, thus causing it to turn off and terminate the current pulse.

Type: Grant

Filed: February 12, 1982

Date of Patent: April 24, 1984

Tuning apparatus and method

Patent number: 4415768

Abstract: Right and left FM stereo signals are combined to form an L plus R-value and subtracted to produce an L minus R value. The L minus R-value is passed through a high-pass filter which mutes the high-frequency portion of the signal only when the amplitude of the signal is low. This is recombined with the L plus R signal to provide a 2L output. A similar process is followed to produce a 2R output.The two left and right outputs are combined and then passed through a mono to stereo converter to produce two phase-shifted signals. These are in turn selectively delayed and passed through respective bandpass filters to mute signal portions between approximately five hundred to one thousand Hz. The combined signals, prior to being converted back to a stereo signal are directed through a second band pass filter to mute the frequency portions other than the five hundred to one thousand Hz level, and these are recombined with the rest of the signal.

Type: Grant

Filed: May 28, 1981

Date of Patent: November 15, 1983

Dimensional sound recording and apparatus and method for producing the same

Patent number: 4309570

Abstract: A sound recording having right and left information channels to drive right and left speakers, respectively. The right information channel has a left main stereo component having a pattern corresponding and similar to a left stereo input signal. In addition, it has a right-to-left compensating component having a pattern that corresponds to an inverted and delayed pattern of a right stereo input signal. In like manner, the right channel has a right main stereo component having a pattern corresponding and similar to the right stereo input signal. It also has a left-to-right compensating component having a pattern which corresponds to an inverted and delayed pattern of the left stereo input signal. The effect is that the main stereo components traveling to the nearest ear of a listener are not diminished substantially, while the main stereo components traveling to the further ear are diminished. The effect is a highly dimensionalized sound pattern.

Type: Grant

Filed: April 5, 1979

Date of Patent: January 5, 1982

Dimensional sound producing apparatus and method

Patent number: 4218585

Abstract: A sound reproducing system having right and left speakers which transmit right and left stereo sounds, respectively. The right signal, in addition to driving the right speaker, is inverted and delayed to produce a compensating signal which is transmitted to the left speaker to produce a delayed compensating sound pattern from the left speaker. The amount of delay and amplitude of the compensating sound pattern is selected so that the major sound pattern emanating from the right speaker is at least partially canceled at the location of the hearer's left ear. The signal for the left speaker is inverted and delayed in a similar manner to produce a compensating sound pattern from the right speaker to at least partially cancel the major sound pattern emanating from the left speaker at the location of the hearer's right ear. The result is to give the hearer a greater dimensionalized impression of the overall sound patterns.

Type: Grant

Filed: April 5, 1979

Date of Patent: August 19, 1980​

Audio amplifier and method of operating the same

Patent number: 4218660

Abstract: A power transformer connected to an amplifier, said transformer being adapted to operate at maximum power output at a relatively high frequency, in the order of 20 KHz. There is a control circuit that produces control pulses at a frequency of 20 KHz. The voltage level at the output of the transformer is compared to the amplitude of the audio signal to be amplified to produce a control signal related to the difference between the two. This control signal acts through a modulator to pass portions of each control pulse, with the duration of the pulse portions that are passed being generally proportional to the magnitude of the control signal. These pulse portions in turn open and close a switch connected to the primary winding of the transformer to control the duration of current pulses which flow through the transformer at a 20 KHz frequency.

Type: Grant

Filed: November 6, 1978

Date of Patent: August 19, 1980

Method and apparatus for reducing noise content in audio signals

Patent number: 3989897

Abstract: Unwanted background noise in audio signals, and particularly in musical material, is significantly reduced by a multiple band dynamic filtering system operated in response to the fundamental and harmonic content and degree of correlation or nonrandomness of the audio signal. A plurality of voltage-controlled band-pass gates or filters are established in the audio signal path for individually and selectively passing frequency content of the audio signal falling within each frequency band. The fundamental and harmonic content of the signal, typically a musical composition, is detected by a corresponding plurality of band-pass signal detectors, the outputs of which are connected to and for operating associated band-pass gates. Normally the band-pass gates are closed blocking any background noise present on the incoming signal.

Type: Grant

Filed: October 25, 1974

Date of Patent: November 2, 1976

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