Patents Assigned to THX Ltd.
  • Patent number: 8027500
    Abstract: A narrow profile speaker unit comprises at least one speaker outputting sound towards an internal surface and through a duct with an output terminus, such as a slot, having a narrow dimension, effectively changing the cross-section of the speaker's audio output wave. A pair of speakers may face one another, outputting sound towards a common output slot. Multiple pairs of speakers may be used to form an inline speaker unit for increased sound output. A slotted speaker unit may include multiple speakers facing the same direction, towards a groundplane or reflecting surface, and having parallel apertures for allowing sound radiation. The speaker units may be integral with or attached to electronic appliances such as desktop computers or flatscreen devices, or may be used in automobiles or other contexts.
    Type: Grant
    Filed: October 6, 2008
    Date of Patent: September 27, 2011
    Assignee: THX Ltd.
    Inventor: Lawrence R. Fincham
  • Patent number: 8004355
    Abstract: A low dissipation, low distortion amplifier includes a driver amplifier stage and a main output stage, with a plurality of impedance networks providing, among other things, feedback paths from outputs of the driver and main output stages to the input of the driver stage. The impedance networks also provide coupling paths from the outputs of the driver and main output stages to the load. The impedance networks can all be formed of resistors, capacitors, or network combinations thereof. An additional feedback path can be added from the load to the driver stage to flatten out the frequency response at low frequencies. The driver and main output stages may be operated in Class AB and B modes respectively, and/or in Class G or H modes. An intermediate amplifier driver stage may be added between the driver and main output stages.
    Type: Grant
    Filed: February 25, 2010
    Date of Patent: August 23, 2011
    Assignee: THX Ltd.
    Inventors: Owen Jones, Lawrence R. Fincham
  • Patent number: 7974425
    Abstract: A sound reproduction system comprises a left and right speakers located in close proximity, and a sound processor which provides audio signals to the pair of speakers. The sound processor preferably derives a cancellation signal from the difference between the left and right channels. The resulting difference signal is scaled, delayed (if necessary), and spectrally modified before being added to the left channel and, in opposite polarity, to the right channel. The spectral modification to the difference channel preferably takes the form of a low-frequency boost over a specified frequency range, in order to restore the correct timbral balance after the differencing process. Additional phase-compensating all-pass networks may be inserted in the difference channel to correct for any extra phase shift contributed by the spectral modifying circuit. The technique may be used in a surround sound system.
    Type: Grant
    Filed: September 17, 2009
    Date of Patent: July 5, 2011
    Assignee: THX Ltd
    Inventor: Lawrence R. Fincham
  • Patent number: 7834702
    Abstract: A dynamic power supply for N amplifiers includes first and second power boost circuits which temporarily boost the positive or negative power supply rail, respectively. A control circuit monitors amplifier output signal levels and provides power boost control signals to the power boost circuits, which temporarily raise the positive supply voltage above the nominal voltage level in tandem with the highest output signal from the N amplifiers and lower the negative supply voltage below the nominal voltage level in tandem with the lowest output signal level from the N amplifiers. The power boost circuits each may be coupled to a reservoir capacitor from which current is drawn to provide the power boost. When inactive, the reservoir capacitors charge up from the respective power supply rails. The dynamic power supply is well suited for audio amplification systems.
    Type: Grant
    Filed: October 16, 2008
    Date of Patent: November 16, 2010
    Assignee: THX Ltd.
    Inventors: Owen Jones, Lawrence R. Fincham
  • Patent number: 7593533
    Abstract: A sound reproduction system comprises a left and right speakers located in close proximity, and a sound processor which provides audio signals to the pair of speakers. The sound processor preferably derives a cancellation signal from the difference between the left and right channels. The resulting difference signal is scaled, delayed (if necessary), and spectrally modified before being added to the left channel and, in opposite polarity, to the right channel. The spectral modification to the difference channel preferably takes the form of a low-frequency boost over a specified frequency range, in order to restore the correct timbral balance after the differencing process. Additional phase-compensating all-pass networks may be inserted in the difference channel to correct for any extra phase shift contributed by the spectral modifying circuit. The technique may be used in a surround sound system.
    Type: Grant
    Filed: June 13, 2007
    Date of Patent: September 22, 2009
    Assignee: THX Ltd.
    Inventor: Lawrence R. Fincham
  • Publication number: 20090220112
    Abstract: A vehicle sound system encompasses a combination of speaker configuration, speaker placement, and sound processing to improve sound quality. A pair of speakers (or rows of speakers) are placed close together and located in the front of the console or dashboard with their geometric center on or near the vehicle's central axis. A sound processor acts to “spread” the sound image produced by the two closely spaced speakers by employing a cross-cancellation technique in which the cancellation signal is derived from the difference between the left and right channels. The resulting difference signal is scaled, delayed (if necessary), and spectrally modified before being added in opposite polarities to the left and right channels. The pair of speakers may be placed on a common baffle or mounting surface or in a common housing enclosure, with sound being carried through one or more ducts and emanating out of a slot.
    Type: Application
    Filed: November 24, 2008
    Publication date: September 3, 2009
    Applicant: THX LTD.
    Inventor: Lawrence R. Fincham
  • Publication number: 20090147980
    Abstract: A narrow profile speaker unit comprises at least one speaker outputting sound towards an internal surface and through a duct with an output terminus, such as a slot, having a narrow dimension, effectively changing the cross-section of the speaker's audio output wave. A pair of speakers may face one another, outputting sound towards a common output slot. Multiple pairs of speakers may be used to form an inline speaker unit for increased sound output. A slotted speaker unit may include multiple speakers facing the same direction, towards a groundplane or reflecting surface, and having parallel apertures for allowing sound radiation. The speaker units may be integral with or attached to electronic appliances such as desktop computers or flatscreen devices, or may be used in automobiles or other contexts.
    Type: Application
    Filed: October 6, 2008
    Publication date: June 11, 2009
    Applicant: THX LTD.
    Inventor: Lawrence R. Fincham
  • Publication number: 20090115531
    Abstract: A dynamic power supply for N amplifiers includes first and second power boost circuits which temporarily boost the positive or negative power supply rail, respectively. A control circuit monitors amplifier output signal levels and provides power boost control signals to the power boost circuits, which temporarily raise the positive supply voltage above the nominal voltage level in tandem with the highest output signal from the N amplifiers and lower the negative supply voltage below the nominal voltage level in tandem with the lowest output signal level from the N amplifiers. The power boost circuits each may be coupled to a reservoir capacitor from which current is drawn to provide the power boost. When inactive, the reservoir capacitors charge up from the respective power supply rails. The dynamic power supply is well suited for audio amplification systems.
    Type: Application
    Filed: October 16, 2008
    Publication date: May 7, 2009
    Applicant: THX LTD.
    Inventors: Owen Jones, Lawrence R. Fincham
  • Publication number: 20090116677
    Abstract: An earphone device comprises an inner casing enclosing one or more miniature drive units, and a movable cap or outer casing that moves relative to the inner casing. The inner casing has an extension member, such as a hollow post, terminating in an acoustic output port. A compressible foam bulb at least partially surrounds the extension member, and is decompressed and compressed by actuation of an adjustable member. The adjustable member may take the form, for example, of a pivoting lever, a helical cam, or a push-rod mechanism, among other things. A flange may be disposed around the periphery of the movable cap, in order to provide a seal surrounding the ear canal region. The compressible material may be gripped by the hollow extension member, and abut the movable cap or flange.
    Type: Application
    Filed: October 31, 2008
    Publication date: May 7, 2009
    Applicant: THX LTD.
    Inventors: Owen Jones, Lawrence R. Fincham
  • Patent number: 7457425
    Abstract: A vehicle sound system encompasses a combination of speaker configuration, speaker placement, and sound processing to improve sound quality. A pair of speakers (or rows of speakers) are placed close together and located in the front of the console or dashboard with their geometric center on or near the vehicle's central axis. A sound processor acts to “spread” the sound image produced by the two closely spaced speakers by employing a cross-cancellation technique in which the cancellation signal is derived from the difference between the left and right channels. The resulting difference signal is scaled, delayed (if necessary), and spectrally modified before being added in opposite polarities to the left and right channels. The pair of speakers may be placed on a common baffle or mounting surface or in a common housing enclosure, with sound being carried through one or more ducts and emanating out of a slot.
    Type: Grant
    Filed: January 8, 2003
    Date of Patent: November 25, 2008
    Assignee: THX Ltd.
    Inventor: Lawrence R. Fincham
  • Patent number: 7433483
    Abstract: A narrow profile speaker unit comprises at least one speaker outputting sound towards an internal surface and through a duct with an output terminus, such as a slot, having a narrow dimension, effectively changing the cross-section of the speaker's audio output wave. A pair of speakers may face one another, outputting sound towards a common output slot. Multiple pairs of speakers may be used to form an inline speaker unit for increased sound output. A slotted speaker unit may include multiple speakers facing the same direction, towards a groundplane or reflecting surface, and having parallel apertures for allowing sound radiation. The speaker units may be integral with or attached to electronic appliances such as desktop computers or flatscreen devices, or may be used in automobiles or other contexts.
    Type: Grant
    Filed: September 8, 2004
    Date of Patent: October 7, 2008
    Assignee: THX Ltd.
    Inventor: Lawrence R. Fincham
  • Publication number: 20080212805
    Abstract: A sound reproduction system includes one or more arrays of drive units, coupled with sound processing allowing improved steerability, directional control, width control, and/or beam overlay. A speaker column may comprise two arrays facing one another, the drive units being perpendicular to the speaker unit front, with the acoustic output of each line array being compressed, turned and output from an elongate slot. The drive units may be staggered with respect to those in the opposing array. The arrays may be arc-shaped else straight. Selective delays to simulate an arced pattern. Differential delays applied to the drive units in a sub-array allow beam steering. Additional drive units, such as high frequency drivers, may be added along the length of the elongate slot or elsewhere to increase the dynamic frequency range of the speaker system. A collocated sound processor and amplifier output stage may be integrated with the speaker unit.
    Type: Application
    Filed: October 16, 2007
    Publication date: September 4, 2008
    Applicant: THX Ltd.
    Inventor: Lawrence R. Fincham
  • Publication number: 20080130905
    Abstract: A sound reproduction system comprises a left and right speakers located in close proximity, and a sound processor which provides audio signals to the pair of speakers. The sound processor preferably derives a cancellation signal from the difference between the left and right channels. The resulting difference signal is scaled, delayed (if necessary), and spectrally modified before being added to the left channel and, in opposite polarity, to the right channel. The spectral modification to the difference channel preferably takes the form of a low-frequency boost over a specified frequency range, in order to restore the correct timbral balance after the differencing process. Additional phase-compensating all-pass networks may be inserted in the difference channel to correct for any extra phase shift contributed by the spectral modifying circuit. The technique may be used in a surround sound system.
    Type: Application
    Filed: June 13, 2007
    Publication date: June 5, 2008
    Applicant: THX LTD.
    Inventor: Lawrence R. Fincham
  • Patent number: 7333154
    Abstract: A technique for managing the production, post-production and distribution of audio-visual projects permits accurate management of production values and thereby allows accurate and measurable reproduction and control. Test signal data is used to assist the operator in insuring the levels are set to the intended display characteristics in the event that factors such as creative lighting or applied effects affect the desired look of the scene. The test signal data may encompass elements that determine resolution, white level, black level, grey steps, frequency response and linearity as well as sound parameters. Chroma channels may exhibit similar signals including a bar pattern that can be used to insure the best colorimetry is maintained. Standard signals may also improve compositing and cross media transfers for matching production values.
    Type: Grant
    Filed: June 15, 2004
    Date of Patent: February 19, 2008
    Assignee: THX, Ltd.
    Inventors: Rick Dean, Dave Schnuelle
  • Patent number: 7254239
    Abstract: A sound reproduction system comprises a left and right speakers located in close proximity, and a sound processor which provides audio signals to the pair of speakers. The sound processor preferably derives a cancellation signal from the difference between the left and right channels. The resulting difference signal is scaled, delayed (if necessary), and spectrally modified before being added to the left channel and, in opposite polarity, to the right channel. The spectral modification to the difference channel preferably takes the form of a low-frequency boost over a specified frequency range, in order to restore the correct timbral balance after the differencing process. Additional phase-compensating all-pass networks may be inserted in the difference channel to correct for any extra phase shift contributed by the spectral modifying circuit. The technique may be used in a surround sound system.
    Type: Grant
    Filed: February 11, 2002
    Date of Patent: August 7, 2007
    Assignee: THX Ltd.
    Inventor: Lawrence R. Fincham
  • Publication number: 20050057691
    Abstract: A technique for managing the production, post-production and distribution of audio-visual projects permits accurate management of production values and thereby allows accurate and measurable reproduction and control. Test signal data is used to assist the operator in insuring the levels are set to the intended display characteristics in the event that factors such as creative lighting or applied effects affect the desired look of the scene. The test signal data may encompass elements that determine resolution, white level, black level, grey steps, frequency response and linearity as well as sound parameters. Chroma channels may exhibit similar signals including a bar pattern that can be used to insure the best colorimetry is maintained. Standard signals may also improve compositing and cross media transfers for matching production values.
    Type: Application
    Filed: June 15, 2004
    Publication date: March 17, 2005
    Applicant: THX Ltd.
    Inventors: Rick Dean, Dave Schnuelle
  • Patent number: 6771323
    Abstract: A technique for managing the production, post-production and distribution of audio-visual projects permits accurate management of production values and thereby allow accurate and measurable reproduction and control. Test signal data is used to assist the operator in insuring the levels are set to the intended display characteristics in the event that factors such as creative lighting or applied effects affect the desired look of the scene. The test signal data may encompass elements that determine resolution, White level, Black level, Grey steps, Frequency response and linearity as well as sound parameters. Chroma channels may exhibit similar signals including a bar pattern that can be used to insure the best colorimetry is maintained. Standard signals may also improve compositing and cross media transfers without extraordinary efforts to match production values.
    Type: Grant
    Filed: November 15, 2000
    Date of Patent: August 3, 2004
    Assignee: THX Ltd.
    Inventors: Rick Dean, Dave Schnuelle
  • Publication number: 20030219137
    Abstract: A vehicle sound system encompasses a combination of speaker configuration, speaker placement, and sound processing to improve sound quality. A pair of speakers (or rows of speakers) are placed close together and located in the front of the console or dashboard with their geometric center on or near the vehicle's central axis. A sound processor acts to “spread” the sound image produced by the two closely spaced speakers by employing a cross-cancellation technique in which the cancellation signal is derived from the difference between the left and right channels. The resulting difference signal is scaled, delayed (if necessary), and spectrally modified before being added in opposite polarities to the left and right channels. The pair of speakers may be placed on a common baffle or mounting surface or in a common housing enclosure, with sound being carried through one or more ducts and emanating out of a slot.
    Type: Application
    Filed: January 8, 2003
    Publication date: November 27, 2003
    Applicant: THX Ltd.
    Inventor: Lawrence R. Fincham