Music Level LED Indicator Circuit

This tutorial help to make Music Level LED Indicator Circuit Light which turn on again and again when music volume goes up or down.

Light move like wave when music get loud fast.

This article tell how circuit work and what parts we need for make it.

What is a Music Level LED Indicator Circuit:

Music Level LED Indicator Circuit is one electronic circuit which works with sound or music and show sound level using LED lights.

People use this circuit in music things like audio player, sound system or for music artist project.

Circuit Working:

Parts List:

Now we look more deep into LED music level indicator circuit.

First small music signal connects to transistor and then this transistor make signal strong.

Then strong signal can turn ON LED lights.

Each LED have some parts to control it.

All parts look same but using diodes is bit little different.

In circuit the diodes are put in special way.

First LED connect direct to ground but other LEDs have extra diodes.

This changes how long LED light stay ON.

Because diode drop voltage then first LED is ON and then the second and then the next.

More diodes need more voltage so light turn ON slow when there are more diodes.

When music goes loud circuit voltage goes high.

This make LEDs ON one by one like switch moving and show bar graph for music volume.

LEDs blink again and again it looks nice and show how loud music is.

LEDs move and change with music because voltage keep changing.

We can change settings of parts for each LED.

This help to change how circuit work for our music and what we like.

Formulas and Calculations:

This formula show how much voltage drops on LED in circuit:

VLED = VBE + Vdiode

What it mean:

• VLED is voltage drop on LED when it turn ON and gives light.
• VBE is voltage drop from base to emitter of transistor.
• Vdiode is voltage drop of diode if diode connect in series with LED.

How to Use Formula:

This formula help us know how much voltage needed to turn ON LED in simple circuit with transistor and maybe diode.

First Check Datasheet:

Look datasheet for transistor to get VBE value and also check LED datasheet for VLED value.

Second Find Vdiode:

If circuit have diode in series then check which type it is.

Mostly silicon diode have drop around 0.7V and check datasheet to be sure.

Third Calculate VLED:

Now add values to get total voltage need:

VLED = VBE + Vdiode

Note:

Actual voltage in circuit will be little different.

Many things can change small amount of voltage.

Tips:

Best way to make LED work good is use power supply with current limit resistor and adjustable voltage and this will help adjust circuit for better LED result.

How to Build:

To build a Music Level LED Indicator Circuit follow the below mentioned steps:

• First collect all parts: emitter resistors, base presets, diodes, LEDs and NPN BC547 transistors.
• Put all parts on circuit board same like in schematic diagram.
• Check NPN BC547 transistor connects in right direction.
• Connection must be correct.
• Place diodes same like in diagram.
• Pattern of diodes should repeat so keep that in mind.
• Every BC547 transistor need emitter resistor to give correct value.
• Set base presets properly so LED lights work as we want.
• Now add PNP BC557 transistor at input side and be sure it work together with other parts.
• Connect power to circuit with correct voltage and polarity.

Test and Adjust:

• Turn ON the circuit and watch how LED lights respond.
• Change base presets to fix LED performance with the music sound.

Conclusion:

We can make Music Level LED Indicator Circuit by using circuit diagram and doing careful testing.

This cool idea mixes music and electronics to show sound level with lights like in diagram.

References:

Simple LED indicator for audio signals