JPS57162593A - Howling preventing device - Google Patents
Howling preventing deviceInfo
- 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
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.
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)
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)
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 |
-
1981
- 1981-03-30 JP JP4817581A patent/JPS57162593A/en active Granted
Patent Citations (1)
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)
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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