Introduction: Sound Reactive LED Display

About: I like electronics, arduino, programming, and motorcycles. Studying food engineering.

Hello Guys!

This is my first Instructable, and I made an arduino based LED display. I hope you'll like it! If you have any questions, feel free to ask them :-)).

The main concept, is that if you light an acrylic sheet (that has something engraved in it) from the bottom, the engraved picture will light up. I wondered what would it look like, if it lights up to the rythm of a music, and I think it turned out great, better than I expected.

Step 1: Choosing a Logo for the Display, Gathering Material and Tools

First, You need a logo that you want to display on the acrylic sheet. I chose the logo of my favorite Hungarian(Europe) rock band, called Tankcsapda. The logo is a round shape with stars and a P letter, as you can see on the picture.

Then, you need the gather the materials for the project:

-Arduino Nano (any arduino would be perfect, but the size matters this is why I chose the Nano)

-USB cable for the Arduino

-Microphone sensor for the Arduino

-5 leds (you can use a led strip and it'll save a lot of time, but I'm new to soldering, and wanted to practice, so I used cables, leds, and soldering :-) )


-a small swich (optional)

-170mm * 150mm * 4mm acrylic sheet

-wooden box for the base

-extra wood (to hold the acrylic sheet in place) - I used a triangle shaped wooden fixing wedges

-power bank (optional)

-black paint (optional)


-Wooden glue


-Soldering station

-Engraving tool

-Computer with Arduino IDE, to program the Arduino ( )

-Cutting tools

-Hot glue tool

-Drill with wooden bits (3mm,5mm,10mm)

Step 2: Designing/makeing the Base

So if you have the wooden box, the next step is to draw some "helping lines", that will make your work easier with the drilling, and glueing. I placed 5 holes on the mid-line for the leds (5mm), a 10mm hole on the side for the microphone sensor, a hole for the small switch, and one for the cable (about 3.5mm). Then I drilled the holes, and glued the extra wooden parts to hold the acrylic sheet in place. You can see on the pictures that I used small gum spacers (4 of them ) on both sides of the acrylic sheet on both sides, to make sure everything will be tight.

Step 3: Building Your Circuit

Sorry for the drawing, but I hope you understand it! :D

I simply connected the negative leg of the leds to a wire that goes to the GND pin on the arduino. I used a small switch also, that I placed on the wire between the GND pin and the closest led, but this is optional.

And I also soldered wires to all the positive legs to be long enough to reach the pins of the arduino.

Step 4: Programming the Arduino

If you dowloaded the Arduino IDE, you need to set your device first.

For me:

Tools-> Board: Arduino Nano, Processor: ATmega328P, Port: COM9

and uploaded the code to the arduino that I uploaded.

Then connected the Microphone sensor 'Out' pin to D13, 'GND' pin to GND and 'VCC' pin to 5V on the arduino.

Also wired the leds: the common longer wire to another GND, and the positive legs of the leds to D2,D3,D4,D5,D6.

Step 5: Engraving the Acrylic Sheet

Note, that you need at least 2 centimeters to hold the acrylic sheet in place so my picture was 15*15 cms, but I used 17*15cm sheet, so the visible display is only 15*15 cm :-).

I printed the logo on a piece of paper that I placed on the downside of the acrylic sheet. Then used magnifier glass to make my work easier and engraved the logo with the smallest bit that was given for the engraving tool.

Step 6: Painting and Assembling

I used matt black paint, and it looked pretty good on the wooden surface! Make sure to test the circuit, before you hotglue the parts to the box! Then I hotglued the microphone sensor, the switch and the leds and placed the acrylic sheet on top. (you can take out the acrylic sheet with force, but it is pretty tight).

I hope you liked this project, if you make it too, please post it in the comment section!

Arduino Contest 2017

Participated in the
Arduino Contest 2017

LED Contest 2017

Participated in the
LED Contest 2017

First Time Author Contest 2018

Participated in the
First Time Author Contest 2018