3909558

Information

• Patent Grant
• 3909558

• References
• Source

• Patent Number

  3,909,558

• Date Filed

  Not available

• Date Issued

  Tuesday, September 30, 1975
  49 years ago

• CPC

  • H04R23/00 - Transducers other than those covered by groups H04R9/00 - H04R21/00
  • H03F13/00 - Amplifiers using amplifying element consisting of two mechanically- or acoustically-coupled transducers

• US Classifications

  • 381 - Electrical audio signal processing systems and devices