Patents by Inventor Joel M. Cohen

Joel M. Cohen 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).

  • Patent number: 4355203
    Abstract: A stereo enhancement system utilizes a difference signal derived from the left and right stereo channels in which the difference signal is delayed, amplified, and then added into the appropriate channels to cancel left/right speaker mixing at the listener's ears, thereby to improve stereo separation without center region distortion. Depending on the amplification level of the difference signal, an increase in the perimeter sound over that produced at the central region gives a "wrap around" effect with only two speakers by increasing the volume of only the left/right directional sound components relative to centrally located sounds which have no left/right directionality. In order to compensate for the angle between the listener and the speakers, a continuously variable delay is provided in the 100 microsecond -1 millisecond range by the utilization of a serial analog delay bucket brigade device. Ultrashort delays are created, in one embodiment, by utilizing equal delays in the left and right stereo channels.
    Type: Grant
    Filed: September 8, 1980
    Date of Patent: October 19, 1982
    Inventor: Joel M. Cohen
  • Patent number: 4308423
    Abstract: A stereo enhancement system utilizes a difference signal derived from the left and right stereo channels in which the difference signal is delayed, amplified, and then added into the appropriate channels to cancel left/right speaker mixing at the listener's ears, thereby to improve stereo separation without center region distortion. Depending on the amplification level of the difference signal, an increase in the perimeter sound over that produced at the central region gives a "wrap around" effect with only two speakers by increasing the volume of only the left/right directional sound components relative to centrally located sounds which have no left/right directionality. In order to compensate for the angle between the listener and the speakers, a continuously variable delay is provided in the 100 microsecond -1 millisecond range by the utilization of a serial-analog delay bucket brigade device. Ultrashort delays are created, in one embodiment, by utilizing equal delays in the left and right stereo channels.
    Type: Grant
    Filed: March 12, 1980
    Date of Patent: December 29, 1981
    Inventor: Joel M. Cohen
  • Patent number: 4283600
    Abstract: A recirculationless concert hall simulation and enhancement system includes a reproduction system having a primary loudspeaker driven from a signal source and a number of auxiliary loudspeakers driven by sequentially delayed replicas of the original signal so as to reproduce the ambience associated with large size concert halls in a considerably smaller listening room without tonal discoloration. In a preferred embodiment total cumulative sequential delays exceed 50 milliseconds to give enhanced ambience, while individual inter-speaker delays are limited to less than 50 milliseconds, so that distinguishable, distinct echoes are not generated.
    Type: Grant
    Filed: May 23, 1979
    Date of Patent: August 11, 1981
    Inventor: Joel M. Cohen
  • Patent number: D254011
    Type: Grant
    Filed: November 7, 1977
    Date of Patent: January 22, 1980
    Inventor: Joel M. Cohen