Patents by Inventor Stephen E. Satra

Stephen E. Satra 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).

  • Audio processing system for restoring bass frequencies
    Patent number: 4698842
    Abstract: An audio processing system for injecting left and right channel audio signals with a signal having a fundamental frequency component that is half the frequency of the highest amplitude low frequency component in the left and right channel audio signals. The left and right channel audio signals are combined to form a monaural signal that is low pass filtered and applied to a demodulator circuit. The demodulator circuit generates a control signal having a frequency that is half the frequency of the highest amplitude frequency component in the signal at the output of the band pass filter. The control signal varies the phase of the signal at the output of the band pass filter according to the polarity of the control signal. The resulting signal is selectively added to the left and right input signals.
    Type: Grant
    Filed: July 11, 1985
    Date of Patent: October 6, 1987
    Assignee: Electronic Engineering and Manufacturing, Inc.
    Inventors: Gregory C. Mackie, Stephen E. Satra, Chih-Ming Chen