The following article presents a simple sound operated/activated amplifier muting circuit which enables the amplifier to silence itself as soon a voice or an external sound occurs across the detector MIC. The circuit was requested by Mr. Seok Sothea.
Technical Specifications
I want to make a circuit about voice interrupt music..this circuit consists of two input, audio input and mic, and one output to amplifier. First, the input from any audio player. While playing, if their is any sound into microphone, audio will become mute. After the sound from microphone is stop, the audio will be increasing its volume rapidly to its initial volume for some seconds. So, can you guide me some sir?This circuit is connected directly to amplifier, if possible it uses power supply from amplifier. I don't know that it is useful or not. But just my idea, i think it make easy for one who control and playing the music, like in the party, club, FM station, or anywhere that play music as background sound, they don't need to decrease or increase the volume of music when they talk and stop to talk on microphone.
The Design
Referring to the shown sound activated amplifier mute circuit below, we see only a single opamp being used for the proposed actions.
The functioning may be understood with the help of the following discussion:
When a external sound hits the MIC, depending upon the setting of VR1, if this sound is strong enough to pull pin#2 potential below the set potential of pin#3, the output instantaneously goes high.
This momentary high charges up the 10uF/25V capacitor and also triggers the NPN BC547 transistor.
The transistors instantly pulls the amplifier input to ground causing the required silencing or muting of the amplifier output.
The above situation persists for a few seconds depending on the values of the 10u cap and the 100k base resistor.
The above may be altered as per requirement for either raising or reducing the mute period of the amplifier.
As the 10uF discharges, the transistor gradually inhibits its conduction thereby causing an exponential or slow rising switch ON of the amplifier until it restores and reaches its full volume.
Circuit Diagram
Questions & Answers
Forgot to mention you it will be installed in my own 5.1 amplifier.
Thanks.
OK, I think the following circuit should be able to do the job for you. Please check it and let me know how it goes…:
Thanks, the time you spent for me to creat this circuit. Definitely I will make this circuit as per ur drawing , because I have a faith in you ,and it will work. once again thanks for 555 timer ic circuit for overhead water tank filling. The circuit has been working well for last two months without any diveation.
Thanks for your kind words, and good to know you trust my circuit diagrams.
If you build it correctly, it should certainly work as expected, if you face any problems, please let me know, I will solve it for you as quickly as possible…
Good Morning sir, Ihave gone through your diagram found very usefull so thanks to you.
I have a request that can u do little modify to make a audio mute circuit. It will be like the gap between two songs there will be no speaker sound and after starting a song that will be hearable from speaker. Hope u understand.
Hi B.Pailan, can you please specify, where exactly do you want the circuit to be installed or used?
Thank you very much for ur reply. Actually I was searching for this type of circuit for the last one year. My point of view is Audio Mute circuit, that is ,when the song will stop and go for next ,the gap between songs there will be no sound from speaker totally silent. when the next song will start then the audio will be heard. This is my requirements. Hope u you understand my criteria if get time please help me .Thanks a lot in advance.
I have learnt alot from you sir. Thanks!
Thank much sir!. You have helped me alot. One more question sir. Can the sound from mic be changed since you have connected from the output of comparator? Can i connect directly from mic to relay sir?
You are welcome Seok, you are right, please take the mic connection directly from pin#2 and not from pin#6 output as wrongly shown in the diagram.
Wow! Very quick. Thank you very much sir! But i miss one point to tell you.sorry sir. I mean there is one sound that go out to amplifier. when the music become mute. The voice from mic goes into amplifier instead. Could it possible sir. Sorry again for missing this point.
I have updated the modifications, please check it out.