JPS54155752A - Acoustic unit - Google Patents

Acoustic unit

Info

Publication number
JPS54155752A
JPS54155752A JP6388978A JP6388978A JPS54155752A JP S54155752 A JPS54155752 A JP S54155752A JP 6388978 A JP6388978 A JP 6388978A JP 6388978 A JP6388978 A JP 6388978A JP S54155752 A JPS54155752 A JP S54155752A
Authority
JP
Japan
Prior art keywords
sound
amplifier
signal
gain
ambient noise
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.)
Pending
Application number
JP6388978A
Other languages
Japanese (ja)
Inventor
Hisatoshi Aoki
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.)
Toshiba Corp
Original Assignee
Toshiba Corp
Tokyo Shibaura 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 Toshiba Corp, Tokyo Shibaura Electric Co Ltd filed Critical Toshiba Corp
Priority to JP6388978A priority Critical patent/JPS54155752A/en
Publication of JPS54155752A publication Critical patent/JPS54155752A/en
Pending legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03G—CONTROL OF AMPLIFICATION
    • H03G3/00—Gain control in amplifiers or frequency changers without distortion of the input signal
    • H03G3/20—Automatic control
    • H03G3/30—Automatic control in amplifiers having semiconductor devices
    • H03G3/32—Automatic control in amplifiers having semiconductor devices the control being dependent upon ambient noise level or sound level

Abstract

PURPOSE:To make it possible to adjust a volume of sound to the best value to an ambient noise constantly by detecting the ambient noise of the acoustic unit such as a TV receiver by a sound-collecting microphone and by automatically adjusting the volume of sound of the acoustic unit depending upon the detection signal. CONSTITUTION:Sound-collecting microphone 5 detects a mixed sound of sound S of a TV receiver and ambient noise N and amplifier 6 amplifies the detection 5 signal up to the same level as S sent from amplifier 7 in the N=0 state and then send it to differential amplifier 8, where a sound signal in phase with S iutputted amplifier 7 is removed. The output signal of amplifier 8, namely, N has a large transient noise removed 9 through clip effect and is sampled by a gate signal from timing pulse generator 10, and it is passed through integrator 11 and operational amplifiers 12 and 14 to control the gain of TV sound circuit 17, so that the gain will be increased with large N while the gain is decreased with small N.
JP6388978A 1978-05-30 1978-05-30 Acoustic unit Pending JPS54155752A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP6388978A JPS54155752A (en) 1978-05-30 1978-05-30 Acoustic unit

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP6388978A JPS54155752A (en) 1978-05-30 1978-05-30 Acoustic unit

Publications (1)

Publication Number Publication Date
JPS54155752A true JPS54155752A (en) 1979-12-08

Family

ID=13242302

Family Applications (1)

Application Number Title Priority Date Filing Date
JP6388978A Pending JPS54155752A (en) 1978-05-30 1978-05-30 Acoustic unit

Country Status (1)

Country Link
JP (1) JPS54155752A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2010102255A (en) * 2008-10-27 2010-05-06 Yamaha Corp Noise estimation apparatus, calling apparatus, and noise estimation method

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2010102255A (en) * 2008-10-27 2010-05-06 Yamaha Corp Noise estimation apparatus, calling apparatus, and noise estimation method

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