JPS57162592A - Echo preventing loudspeaking device - Google Patents

Echo preventing loudspeaking device

Info

Publication number
JPS57162592A
JPS57162592A JP4753781A JP4753781A JPS57162592A JP S57162592 A JPS57162592 A JP S57162592A JP 4753781 A JP4753781 A JP 4753781A JP 4753781 A JP4753781 A JP 4753781A JP S57162592 A JPS57162592 A JP S57162592A
Authority
JP
Japan
Prior art keywords
signal
reference signal
entered
transducer
erase
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
JP4753781A
Other languages
English (en)
Other versions
JPH0217981B2 (ja
Inventor
Akihiko Tsukudai
Hidenori Ito
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
NEC Corp
Original Assignee
NEC Corp
Nippon Electric Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by NEC Corp, Nippon Electric Co Ltd filed Critical NEC Corp
Priority to JP4753781A priority Critical patent/JPS57162592A/ja
Publication of JPS57162592A publication Critical patent/JPS57162592A/ja
Publication of JPH0217981B2 publication Critical patent/JPH0217981B2/ja
Granted legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
    • H04R3/00—Circuits for transducers, loudspeakers or microphones
    • H04R3/02—Circuits for transducers, loudspeakers or microphones for preventing acoustic reaction, i.e. acoustic oscillatory feedback

Landscapes

  • Health & Medical Sciences (AREA)
  • General Health & Medical Sciences (AREA)
  • Otolaryngology (AREA)
  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Acoustics & Sound (AREA)
  • Signal Processing (AREA)
  • Circuit For Audible Band Transducer (AREA)
  • Interconnected Communication Systems, Intercoms, And Interphones (AREA)
  • Cable Transmission Systems, Equalization Of Radio And Reduction Of Echo (AREA)
JP4753781A 1981-03-31 1981-03-31 Echo preventing loudspeaking device Granted JPS57162592A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP4753781A JPS57162592A (en) 1981-03-31 1981-03-31 Echo preventing loudspeaking device

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP4753781A JPS57162592A (en) 1981-03-31 1981-03-31 Echo preventing loudspeaking device

Publications (2)

Publication Number Publication Date
JPS57162592A true JPS57162592A (en) 1982-10-06
JPH0217981B2 JPH0217981B2 (ja) 1990-04-24

Family

ID=12777877

Family Applications (1)

Application Number Title Priority Date Filing Date
JP4753781A Granted JPS57162592A (en) 1981-03-31 1981-03-31 Echo preventing loudspeaking device

Country Status (1)

Country Link
JP (1) JPS57162592A (ja)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0342782A2 (en) * 1988-03-23 1989-11-23 Central Institute For The Deaf Electroacoustic system with electronic filters
US5357251A (en) * 1988-03-23 1994-10-18 Central Institute For The Deaf Electronic filters, signal conversion apparatus, hearing aids and methods
US5475759A (en) * 1988-03-23 1995-12-12 Central Institute For The Deaf Electronic filters, hearing aids and methods

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS561649A (en) * 1979-06-19 1981-01-09 Nec Corp Conference telephone equipment

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS561649A (en) * 1979-06-19 1981-01-09 Nec Corp Conference telephone equipment

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0342782A2 (en) * 1988-03-23 1989-11-23 Central Institute For The Deaf Electroacoustic system with electronic filters
US5357251A (en) * 1988-03-23 1994-10-18 Central Institute For The Deaf Electronic filters, signal conversion apparatus, hearing aids and methods
US5475759A (en) * 1988-03-23 1995-12-12 Central Institute For The Deaf Electronic filters, hearing aids and methods

Also Published As

Publication number Publication date
JPH0217981B2 (ja) 1990-04-24

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