How to Control RGB LEDs With Sound Input Using an Arduino

Controlling the brightness of RGB LEDs based on sound input is a fascinating application of electronics that can result in stunning light displays that respond to audio input. In this tutorial, we will guide you through the process of building a circuit that takes audio input and translates it into dynamic light patterns. By the end of this tutorial, you will have an exciting and interactive project that responds to the beat of your favorite music or even the volume of your voice! Whether you are a hobbyist, a student, or a professional, this tutorial will provide you with the necessary knowledge to create a fascinating project that combines electronics and sound. So, let's get started!

Arduino Nano ≈ $10 / unit

https://www.amazon.com/Deegoo-ATmega328P-Microcontroller-Board-Arduino/dp/B07R9VWD39/ref=sr_1_5?crid=1YLV2AHFD2D4I&keywords=arduino+nano&qid=1682722206&sprefix=arduino+nano%2Caps%2C350&sr=8-5

Breadboard ≈ $2 / unit

https://www.amazon.com/Breadborad-Solderless-Breadboards-Distribution-Connecting/dp/B082VYXDF1/ref=sr_1_1_sspa?crid=3N1TBD3MQQ5GV&keywords=breadboards&qid=1682722356&sprefix=breadboards%2Caps%2C124&sr=8-1-spons&psc=1&spLa=ZW5jcnlwdGVkUXVhbGlmaWVyPUExUVk5Sk5ISUxJV0tWJmVuY3J5cHRlZElkPUEwOTc1MjAwMjhSSVlBRDRHMlU1VCZlbmNyeXB0ZWRBZElkPUEwOTM3NjM1MUxSWVZFMzU0QUdKWiZ3aWRnZXROYW1lPXNwX2F0ZiZhY3Rpb249Y2xpY2tSZWRpcmVjdCZkb05vdExvZ0NsaWNrPXRydWU=

DAOKI Sound Sensor ≈ $1 / unit

ZW5jcnlwdGVkUXVhbGlmaWVyPUEyWDFMNktDTVVaRURDJmVuY3J5cHRlZElkPUExMDM1ODE3MjVMTU4yR0ZBTjdFMiZlbmNyeXB0ZWRBZElkPUEwODE1MDA2MlhWTU5KTEtCRDhESSZ3aWRnZXROYW1lPXNwX2F0ZiZhY3Rpb249Y2xpY2tSZWRpcmVjdCZkb05vdExvZ0NsaWNrPXRydWU

RGB LEDs WS2812B ≈ $5 / ft

https://www.amazon.com/WESIRI-Programmable-Individual-Addressable-Non-Waterproof/dp/B07CBS3CN7/ref=sr_1_7?crid=2EZX4HPFRX7GF&keywords=WS2812B&qid=1682722477&sprefix=ws2812b%2Caps%2C153&sr=8-7&th=1

Jumper Wires ≈ $0.08 / unit

https://www.amazon.com/Elegoo-EL-CP-004-Multicolored-Breadboard-arduino/dp/B01EV70C78/ref=sr_1_1_sspa?crid=EPVDAPAWR544&keywords=jumper%2Bwires%2Bvariety&qid=1682722597&sprefix=jumper%2Bwires%2Bvariety%2Caps%2C126&sr=8-1-spons&spLa=ZW5jcnlwdGVkUXVhbGlmaWVyPUFBRVBFSUxJOU5RQVUmZW5jcnlwdGVkSWQ9QTA2OTI2MjMxNU5KT0FISzA3RTVaJmVuY3J5cHRlZEFkSWQ9QTA5NDUzMjExRUtQVk9KOTU5MVg5JndpZGdldE5hbWU9c3BfYXRmJmFjdGlvbj1jbGlja1JlZGlyZWN0JmRvTm90TG9nQ2xpY2s9dHJ1ZQ&th=1

5v Power ≈ $7 / unit

https://www.amazon.com/Miady-5000mAh-Portable-Charger-Android/dp/B08T8TDS8S/ref=sr_1_2?crid=25B3DEY5UKM29&keywords=portable+charger+5v&qid=1682723024&s=wireless&sprefix=mini+portable+charger+5v%2Cmobile%2C119&sr=1-2

Follow this schematic. Note that you should use a 5v battery, not a 9v. Additionally, the sound sensor in the image is represented by a TMP.

Copy this code into your Arduino IDE:

//Include libraries here

#include <Adafruit_NeoPixel.h>

//Define values here

#define NUM_LEDS 24 // number of LEDs

#define LED_PIN 7 // LED data pin

#define SOUND_PIN A1 // sound sensor output pin

#define NUM_READINGS 10 // number of readings to average

//LED variable setup

int readingsTotal = 0; // sum of past readings

int readingsIndex = 0; // index of the oldest reading in the sum

int readings[NUM_READINGS]; // array to store past readings

int currentBrightness = 0; // current LED brightness

int newBrightness = 0; // new LED brightness

int fadeAmount = 10; // amount to fade the brightness with each loop iteration

// initialize the NeoPixel strip

Adafruit_NeoPixel strip(NUM_LEDS, LED_PIN, NEO_GRB + NEO_KHZ800);

void setup() {

 //Setup for LEDs

 strip.begin();

 strip.show(); // Initialize all pixels to 'off'

 pinMode(SOUND_PIN, INPUT);

 for (int i = 0; i < NUM_READINGS; i++) {

  readings[i] = 0; // initialize all readings to zero

 }

} // <-- closing bracket for setup()

void loop() {

 controlLEDs();

}

void controlLEDs() {

 int soundValue = analogRead(SOUND_PIN); // read the sound sensor value

 readingsTotal = readingsTotal - readings[readingsIndex] + soundValue; // update the sum of past readings

 readings[readingsIndex] = soundValue; // store the new reading in the array

 readingsIndex = (readingsIndex + 1) % NUM_READINGS; // update the index to wrap around the array

 int average = readingsTotal / NUM_READINGS; // calculate the moving average

 newBrightness = map(average, 0, 1023, 0, 255); // map the average value to the LED brightness range

 if (newBrightness > currentBrightness) {

  currentBrightness = min(currentBrightness + fadeAmount, newBrightness); // smoothly increase the brightness

 }

 else if (newBrightness < currentBrightness) {

  currentBrightness = max(currentBrightness - fadeAmount, newBrightness); // smoothly decrease the brightness

 }

 for (int i = 0; i < NUM_LEDS; i++) {

  if (i < 8) {

   // LEDs 0-8 are affected by the sound sensor

   strip.setPixelColor(i, strip.Color(0, 0, currentBrightness)); // set the color and brightness of each LED

  } else {

   // LEDs 9-24 are not affected by the sound sensor and have a fixed brightness of 50

   strip.setPixelColor(i, strip.Color(0, 0, 50)); // set the color and brightness of each LED

  }

 }

 strip.show(); // update the LED strip with the new colors and brightness

 delay(10); // add a small delay to smooth out the brightness changes

 fadeAmount = 20; // set the fade amount to 20 for faster changes

}

You can modify this section of code to fit your project!

NUM_LEDS.........................................................Change this number to match the number of LEDs you're using!

LED_PIN...............................................................Change this to match the pins that are available to you!

SOUND_PIN .........................................................Change this to match the pins that are available to you!

NUM_READINGS ................................................Change this to fit the number of readings to average!

Plug the Arduino into your laptop, and make sure it recognizes the port. If you get an error that reads:

Upload error: failed uploading: uploading error: exit status 1

You may have multiple tabs or Arduino IDEs open, close them. Then compile and upload your sketch!

You're done!

In this tutorial, we have shown you how to create a sound-responsive RGB LED system using an Arduino board, a microphone module, and RGB LED strips. By following the steps outlined in this tutorial, you can create your own dynamic light show that responds to sound input, providing a fun and interactive experience for you and your audience.

Happy building!