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Noise Cancellation with Op-Amp(IC 741)

I was very much inspired by Bose. They are using a technique known as active noise cancellation. They are using a processor in their earphones and headphones.
When any noise enters into the headphones or earphones the processors which are present in it make the signal which is equal in magnitude but opposite in phase. Thus the signal which is generated by processors is added with the actual noise signal due to which their addition almost becomes zero and you can just listen the music very clearly as compared with the headphones of other companies (I'm not promoting any company). Since they are using processors that require an external power supply for its operation, therefore, it is known as the active noise cancellation technique.
Now talking about my idea I didn't made any prototype of this project that's why I can't comment on its actual working but during simulation, it is working properly.
So let's start with our project.

Components required:-
1) Op-Amp (IC 741)
2) Resistors and one variable resistor.
3) Battery (9V)
4) Jumpers(Wires)
5) MIC
6) AND gate(Ic 7408) OR two-transistors 
(Since we require only one AND gate so if you want to save space in your project then you can make an AND gate with the help of 2-transistors)

Circuit Diagram:-
So as you can see in the diagram that the positive end of the mic is connected to the positive terminal of 9v with a 10k resistor in between them.
AND gate is connected to the input of the mic while the other end of the AND gate is connected to the ground. Here I had made AND gate with the help of transistors [Q1 and Q2].
The output of the AND gate is connected to the 3rd pin of op-Amp with a 100k resistor in between them.
The audio-signal is also given to the 3rd pin of op-Amp.
We are using a variable resistor to increase or decrease the sound level which is connected between the 2nd and 6th pin of op-Amp and the 2nd pin is connected to the ground with a 1k resistor.   

Working Of The Project:-
We are using Op-Amp as Summing Amplifier or as an adder in this project. Whenever any noise is produced in the external environment then the mic converts the noise signal into an electrical signal. This signal is given to one of the terminals of the AND gate.
Now as the other terminal of the AND gate is grounded therefore ideally at the output we should get zero signal but practically we get some signal at the output of the AND gate so to reduce that noise signal we connect a 100k resistor between the output of the AND gate & 3rd pin of op-Amp.
Now since we had also connected the audio signal to the 3rd pin of op-Amp due to which that noise signal which is almost negligible gets added with the audio signal (zero + audio-signal). Due to which at the output we are only getting the amplified form of the audio signal.
The variable resistor(feed-back resistor) is used to increase or decrease the sound level or amplitude of the audio signal.  
So as usual I conclude my explanation by leaving this short video.

Here is the PDF of pcb designing 
I'm also providing it's Gerber file of this project 

Here is the photo of it this pic is for them who are not going for printed circuit.

Please let me know whether you liked my idea and if you have any ideas or any suggestions to improve this project then please let me know in the comments section.  


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