JPS57162593A - Howling preventing device - Google Patents

Howling preventing device

Info

Publication number
JPS57162593A
JPS57162593A JP4817581A JP4817581A JPS57162593A JP S57162593 A JPS57162593 A JP S57162593A JP 4817581 A JP4817581 A JP 4817581A JP 4817581 A JP4817581 A JP 4817581A JP S57162593 A JPS57162593 A JP S57162593A
Authority
JP
Japan
Prior art keywords
signal
attenuation
band
degree
certain
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
JP4817581A
Other languages
Japanese (ja)
Other versions
JPS6310639B2 (en
Inventor
Toshiyuki Sakai
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.)
Individual
Original Assignee
Individual
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 Individual filed Critical Individual
Priority to JP4817581A priority Critical patent/JPS57162593A/en
Publication of JPS57162593A publication Critical patent/JPS57162593A/en
Publication of JPS6310639B2 publication Critical patent/JPS6310639B2/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)

Abstract

PURPOSE:To prevent the howling, by delaying the band signals divided into plural bands by a certain period of time, measuring the mean energy of the band signal with every certain time and comparing the mean energy with the threshold value to control the degree of attenuation. CONSTITUTION:The signal supplied through an input terminal 100 is divided for the band by (n) units of band filters 20(1-n) and led to a delay circuit 30(1-n) to be delayed by a certain time. At the same time, the signal is led to mean energy measuring circuits 60(1-n) to obtain mean energies W1-Wn with every certain time. These energies are compared 70(1-n) with the threshold value WO. The comparators 70(1-n) supply a signal (1) to variable attenuators 40 (1-n) in the case of W1-Wn>WO to carry out a certain attenuation beta. The attenuator 40 contains the control signal holding function and the multiplying function and holds the degree of attenuation until the next input signal and then revises the degree of attenuation with a new input. The outputs of the attenuators 40 are added 500 to obtain an output 800. In such way, the howling can be automatically prevented without lowering the sound quality.
JP4817581A 1981-03-30 1981-03-30 Howling preventing device Granted JPS57162593A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP4817581A JPS57162593A (en) 1981-03-30 1981-03-30 Howling preventing device

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP4817581A JPS57162593A (en) 1981-03-30 1981-03-30 Howling preventing device

Publications (2)

Publication Number Publication Date
JPS57162593A true JPS57162593A (en) 1982-10-06
JPS6310639B2 JPS6310639B2 (en) 1988-03-08

Family

ID=12796045

Family Applications (1)

Application Number Title Priority Date Filing Date
JP4817581A Granted JPS57162593A (en) 1981-03-30 1981-03-30 Howling preventing device

Country Status (1)

Country Link
JP (1) JPS57162593A (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS59161995A (en) * 1983-03-07 1984-09-12 Matsushita Electric Ind Co Ltd Howling suppressing device
JPS62198298A (en) * 1986-02-18 1987-09-01 エヌ・ベ−・フイリツプス・フル−イランペンフアブリケン Automatic control amplifier
KR101204239B1 (en) 2011-03-31 2012-11-26 김철희 the device for preventing howling against audio system and the method for preventing the same thereof

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5642413A (en) * 1979-09-14 1981-04-20 Victor Co Of Japan Ltd Sound-field singla correcting device

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5642413A (en) * 1979-09-14 1981-04-20 Victor Co Of Japan Ltd Sound-field singla correcting device

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS59161995A (en) * 1983-03-07 1984-09-12 Matsushita Electric Ind Co Ltd Howling suppressing device
JPH0444480B2 (en) * 1983-03-07 1992-07-21 Matsushita Electric Ind Co Ltd
JPS62198298A (en) * 1986-02-18 1987-09-01 エヌ・ベ−・フイリツプス・フル−イランペンフアブリケン Automatic control amplifier
KR101204239B1 (en) 2011-03-31 2012-11-26 김철희 the device for preventing howling against audio system and the method for preventing the same thereof

Also Published As

Publication number Publication date
JPS6310639B2 (en) 1988-03-08

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