Patents by Inventor John J. Virva

John J. Virva 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).

  • Fine tuned, column speaker system
    Patent number: 4164988
    Abstract: A loudspeaker system is disclosed having a rigid framework which contains a high compliance loudspeaker connected to an adjustable air column tube. The adjustable air column tube provides exact 1/4 wavelength tuning for the speaker system, to further improve its low frequency response, in accordance with tuned enclosure theory.
    Type: Grant
    Filed: August 25, 1976
    Date of Patent: August 21, 1979
    Assignee: Admiral Corporation
    Inventor: John J. Virva