Patents by Inventor Johan van der Werff

Johan van der Werff 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).

  • System of sound transducers with controllable directional properties
    Patent number: 7343018
    Abstract: The invention relates to loudspeaker systems or loudspeaker columns as used in public address systems and at (pop) concerts. Such systems heretofore possess a frequency-dependent coverage angle and strong second and third order side lobes. The invention describes formulae of the voltage to be applied to the separate loudspeakers of the loudspeaker column, which makes it possible to realize the constant coverage angle over the entire frequency range and to suppress the side lobes to a far-reaching extent.
    Type: Grant
    Filed: September 12, 2001
    Date of Patent: March 11, 2008
    Assignee: PCI Corporation
    Inventor: Johan van der Werff