Tsukure Studio Audio Level Indicator

This project explores sound and light b y creating a sound / audio level LED meter circuit. It can be used as noise meter, loudness meter, sound pressure indicator or VU level meter and also for variety of other related tasks. The circuit is using an electret microphone to detect sound and shows visual indication of LEDs.

This sound to light LED project uses 36 LEDs, 15 transistors and other components. The main circuit of sound detector, amplification and controlling is built around first 3 transistors. The electret microphone detects sound signals and changes them into electrical audio signals, these electrical audio signals are then amplified by the transistors.

The circuit is quite sensitive due for which it can be used for many purposes like for example it can also be used as a sound origin direction finder etc. The sensitivity can be controlled by adjusting the 100K variable resistor or you can also use a 100K potentiometer. For more decreasing the sensitivity you can also use a higher value variable resistor or potentiometer in the place of 100K like 200K or 300K etc.

The operating voltage of the circuit is 12 volt DC. But you can also operate the circuit with 9 volt DC. For doing so use 2 LEDs in the place of three in each line and change the current limiting resistors R7 to R19 to 180 ohms.

Let's Get Started!

Below you will find a list of bits to gather before hand, followed by a detailed schematic. Using a breadboard lay out the components and connect them together as shown. Alternatively you can purchase this module from our shop and simply solder the components in the places indicated on the quality assured printed circuit boards provided.

What You Need...

2 104 (100nF / 0.1uF) Capacitor (Ceramic)
1 10uF Capacitor (Polarized)
2 PCB Mount 2-Pin Screw Terminal Block Connector (Other)
13 1N4148 Diode
24 5mm Green (Diffused) LED
6 5mm Red (Diffused) LED
6 5mm Yellow (Diffused) LED
1 Tsukure Studio - Audio Level Indicator PCB
2 10K
[ Brown, Black, Black, Red ]
Resistor (0.25 Watt)
1 1K2
[ Brown, Red, Black, Brown ]
Resistor (0.25 Watt)
1 220K
[ Red, Red, Black, Orange ]
Resistor (0.25 Watt)
11 5K1
[ Green, Brown, Black, Brown ]
Resistor (0.25 Watt)
1 620K
[ Blue, Red, Black, Orange ]
Resistor (0.25 Watt)
11 75R
[ Violet, Green, Black, Gold ]
Resistor (0.25 Watt)
1 10K (103) Resistor (Trim Potentiometer)
15 2N3904 Transistor (NPN)

NB: Any resistor colour codes specified relate to 5 band resistor codes, the 5th band has not been shown intentionally. The 5th band indicates the resistor tolerence, we use only the highest tolerence resistors in our products.

Take a Closer Look!

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Just An Idea!

This project is currently just an idea, a prototype! This is how we begin our journey of discovery and welcome you to join us.

Why not have a go at making this idea into a working project.


3D Model

Click on the model below and move your mouse to rotate or if you're feeling a little adventurous, why not click the "ZOOM" link and take a closer look!

[ OBJ & MTL ]

Required Products

You can purchase this, and supporting modules direct from our shop;

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