Patents Assigned to Sonic Research Inc.
  • Patent number: 4009885
    Abstract: A magnetic stereo phonograph pick-up cartidge, including a removable stylus assembly of low mass which includes means for precisely aligning the armature with respect to the pole pieces. A boss on the stylus assembly and a mating aperture on the cartridge body assure alignment in the first instance, and a symmetrical, rubber, armature-pivot block is so positioned that perfect alignment between armature and pole pieces, and a proper tracking angle, are achieved only when the stylus is on a recording. The stylus assembly further includes a permanent magnet for energizing the armature, mounted so as to minimize interaction with the pole pieces and eliminate any distortion of the armature, and so provide a more linear, distortion-free response.
    Type: Grant
    Filed: September 8, 1975
    Date of Patent: March 1, 1977
    Assignee: Sonic Research Inc.
    Inventor: Peter E. Pritchard