EP 0662268 A1 19950712 - METHOD AND DEVICE FOR AUTOMATIC GAIN CONTROL IN AN AMPLIFIER OF AN ELECTROACOUSTIC SYSTEM, PARTICULARLY FOR MOTOR VEHICULES.
Title (en)
METHOD AND DEVICE FOR AUTOMATIC GAIN CONTROL IN AN AMPLIFIER OF AN ELECTROACOUSTIC SYSTEM, PARTICULARLY FOR MOTOR VEHICULES.
Title (de)
VERFAHREN UND ANORDNUNG ZUR AUTOMATISCHER VERSTARKUNGSSTEUERUNG EINES VERSTARKER IN EINEM FAHRZEUG.
Title (fr)
PROCEDE ET DISPOSITIF DE COMMANDE AUTOMATIQUE DU GAIN D'UN AMPLIFICATEUR D'UN SYSTEME ELECTROACCOUSTIQUE, NOTAMMENT POUR VEHICULE AUTOMOBILE.
Publication
Application
Priority
- FR 9300905 W 19930921
- FR 9211268 A 19920922
Abstract (en)
[origin: FR2696060A1] The device comprises both in the processing chain for the complex signal from the microphone (10) and in the processing chain for the effective signal output from the gain-controlled amplifier (1), a first high-pass filtering stage with low switch-off frequency and a second high-pass filtering stage with a medium switch-off frequency and presenting an attenuation of at least 30 dB at approximately 100 Hz. There are further provided first auxiliary comparison means (35) comparing the respective levels of signals taken before and after the first high-pass filtering stage. Said means (35) are used alone in the case where the electroacoustic system is autostable beyond the switch-off frequency of the first high-pass filtering stage to decide on possible blocking of the amplifier gain. Said auxiliary comparison means may be also used in combination with second auxiliary comparison means (38) arranged in the processing chain for the effective signal, or in combination with a equalizer (7).
IPC 1-7
IPC 8 full level
H03G 3/32 (2006.01)
CPC (source: EP US)
H03G 3/32 (2013.01 - EP US)
Citation (search report)
See references of WO 9407306A1
Designated contracting state (EPC)
AT BE CH DE DK ES GB IT LI NL PT SE
DOCDB simple family (publication)
FR 2696060 A1 19940325; FR 2696060 B1 19970214; EP 0662268 A1 19950712; US 5557237 A 19960917; WO 9407306 A1 19940331
DOCDB simple family (application)
FR 9211268 A 19920922; EP 93920901 A 19930921; FR 9300905 W 19930921; US 40685095 A 19950322