Sound Operated Music Bell Circuit is small project that play music when it hear sound like clap or knock.
It use microphone to catch sound and then start music using some small electronic parts.
This circuit is fun, easy to make, and good for hobby or decoration use.
What is a Sound Operated Music Bell Circuit:
It is small electric circuit that make music bell sound when it hear some outside sound or noise.
It use microphone to catch sound and then make nice music using small sound maker part.
People use this for fun, decoration or small hobby project.
Exploring the Potential of Sound Operated Music Bells:
There is many ways to use sound operated music bell.
We can put it near window so it play soft music when wind is blowing or make it play sound when someone knocks the door.
Final design is very nice and you can change things to make it how we like.
Now it is the time to start fun and exciting making of this sound music bell circuit.
But first we need to understand how it work inside and what parts it have and what each parts do.
Circuit Working:
Parts List:
| Component | Value | Quantity |
|---|---|---|
| Resistors (All resistors are 1/4 watt unless specified) | ||
| R1 10k | 1 | |
| R2 470k | 1 | |
| R3 2.2k | 1 | |
| R4 150k | 1 | |
| R5 100Ω | 1 | |
| Preset VR1 1M | 1 | |
| Capacitors | ||
| C1 Electrolytic 22µF 16V | 1 | |
| C2 Ceramic 0.1µF | 1 | |
| C3 Ceramic 0.22µF | 1 | |
| C4 Electrolytic 220µF 10V | 1 | |
| C5 Ceramic 0.01µF | 1 | |
| Semiconductors | ||
| Diode 1N4007 | 1 | |
| Transistor BC547 | 1 | |
| Transistor 2N2222 | 1 | |
| IC1 555 | 1 | |
| IC2 UM66 | 1 | |
| Electret Mic | 1 | |
| Speaker 8Ω | 1 | |
| Push button switch | 1 |
IC1 555 timer is very important part in this circuit.
It work in Class C mode and it react to sound around it.
When VR1 preset is turn to highest value then IC1 can keep working for around 30 seconds.
But we can change this time by adjusting VR1.
The time T can be found using a formula.
In this circuit VR1 is the resistance that control the time.
Next the music part like IC2 UM66 has 64 notes inside it.
It plays them one by one until it hear a clap sound.
It start when the timer is turned ON.
Pin 3 of IC555 connects to 1N4001 diode and then connect to pin 2 of IC2 UM66.
When UM66 get power it send small music signal to base of T2 transistor 2N2222.
This transistor act like a platform to make music sound.
Formulas:
This formula is used to find the time for the Sound Operated Music Bell Circuit:
T = 1.1 × VR1 × C1
where:
- T is time in seconds how long the circuit stay ON after hearing a sound.
- VR1 is a preset like small knob resistor we can change to set time or how sensitive the circuit is.
- C1 is a capacitor it help control how long the action happens.
Note:
This formula uses the values of VR1 and C1 to make it easy to find the time T.
We can turn VR1 to make the circuit work longer or at shorter time.
How to Build:
To build a Sound Operated Music Bell Circuit follow the below mentioned steps for connection:
- First collect all parts shown in the circuit diagram.
- Start with the circuit layout of sound operated music bell.
- Step one connect the 555 timer IC and follow the diagram and connect all pins properly.
- Be sure to put the variable resistor VR1 and wire it correctly using the formula we saw before.
- Now add the melody IC UM66 into the circuit.
- Connect pin 3 of the 555 IC to a 1N4001 diode then connect that to pin 2 of UM66.
- This setup starts the melody when sound is detected.
- Next connect the transistor 2N2222.
- This part changes the small electric signal into music we can hear.
- Follow the diagram and connect the base of transistor to UM66 output and also connect collector and emitter properly.
- Now connect the 4 ohm speaker to transistors collector and emitter and through this speaker will play the sound.
- After putting all parts together time to test the music bell!
- Switch ON the circuit and see how it reacts to nearby sounds.
- To change how long the music plays turn VR1 a little until happy with result.
- Also check the volume and be sure everything is working fine.
- The best thing about this project is how simple and fun it is!
- The music bell will play nice tune when it hears sound around it and we can place it anywhere!
- Try near a window, door or any fun spot and enjoy the special melodies that respond to sound.
Conclusion
Putting a sound operated music bell circuit at home or work place is fun and creative way to bring music around us.
When it hear the sound the circuit uses microphone to start and play music.
If anyone is having any question or want to know more about this circuit feel free to ask in the comments below
Enjoy learning and have fun exploring more about sound operated music bells!