Sound Reactive Disco Speaker
This sound-reactive LED Bluetooth speaker is designed for someone who enjoys partying, music, and attention-grabbing on a tight budget. The beat and notes of the music will cause the LED lights to flash. The mirrored outer section functions similarly to a disco ball, saving the user from having to drill a hole in the ceiling.
Parts, Tools, Supplies
- LED Strips
- Breadboard
- Arduino Uno
- Wire Cutter
- Sound Amplifier
- Bluetooth Speaker
- USB A-B Cable
- Sharp utility knife
- Hot melt glue gun
- Soldering iron and Solder
- Third hand tool
- Tweezers
- Small needlenose plier
- Battery pack
- Bluetooth speaker
- Mirror acrylic sheet
Circuit Diagram and Code
/*
LED VU meter for Arduino and Adafruit NeoPixel LEDs.
Hardware requirements:
- Most Arduino or Arduino-compatible boards (ATmega 328P or better).
- Adafruit Electret Microphone Amplifier (ID: 1063)
- Adafruit Flora RGB Smart Pixels (ID: 1260)
OR
- Adafruit NeoPixel Digital LED strip (ID: 1138)
- Optional: battery for portable use (else power through USB or adapter)
Software requirements:
- Adafruit NeoPixel library
Connections:
- 3.3V to mic amp +
- GND to mic amp -
- Analog pin to microphone output (configurable below)
- Digital pin to LED data input (configurable below)
See notes in setup() regarding 5V vs. 3.3V boards - there may be an
extra connection to make and one line of code to enable or disable.
Written by Adafruit Industries. Distributed under the BSD license.
This paragraph must be included in any redistribution.
*/
#include <Adafruit_NeoPixel.h>
#define N_PIXELS 4// Number of pixels in strand
#define MIC_PIN A1 // Microphone is attached to this analog pin
#define LED_PIN 1 // NeoPixel LED strand is connected to this pin
#define DC_OFFSET 0 // DC offset in mic signal - if unusure, leave 0
#define NOISE 20 // Noise/hum/interference in mic signal
#define SAMPLES 100 // Length of buffer for dynamic level adjustment
#define TOP (N_PIXELS + 2) // Allow dot to go slightly off scale
#define PEAK_FALL 8 // Rate of peak falling dot
byte
peak = 0, // Used for falling dot
dotCount = 0, // Frame counter for delaying dot-falling speed
volCount = 0; // Frame counter for storing past volume data
int
vol[SAMPLES], // Collection of prior volume samples
lvl = 10, // Current "dampened" audio level
minLvlAvg = 0, // For dynamic adjustment of graph low & high
maxLvlAvg = 512;
Adafruit_NeoPixel
strip = Adafruit_NeoPixel(N_PIXELS, LED_PIN, NEO_GRB + NEO_KHZ800);
void setup() {
// This is only needed on 5V Arduinos (Uno, Leonardo, etc.).
// Connect 3.3V to mic AND TO AREF ON ARDUINO and enable this
// line. Audio samples are 'cleaner' at 3.3V.
// COMMENT OUT THIS LINE FOR 3.3V ARDUINOS (FLORA, ETC.):
// analogReference(EXTERNAL);
memset(vol, 0, sizeof(vol));
strip.begin();
}
void loop() {
uint8_t i;
uint16_t minLvl, maxLvl;
int n, height;
n = analogRead(MIC_PIN); // Raw reading from mic
n = abs(n - 512 - DC_OFFSET); // Center on zero
n = (n <= NOISE) ? 0 : (n - NOISE); // Remove noise/hum
lvl = ((lvl * 7) + n) >> 3; // "Dampened" reading (else looks twitchy)
// Calculate bar height based on dynamic min/max levels (fixed point):
height = TOP * (lvl - minLvlAvg) / (long)(maxLvlAvg - minLvlAvg);
if(height < 0L) height = 0; // Clip output
else if(height > TOP) height = TOP;
if(height > peak) peak = height; // Keep 'peak' dot at top
// Color pixels based on rainbow gradient
for(i=0; i<N_PIXELS; i++) {
if(i >= height) strip.setPixelColor(i, 0, 0, 0);
else strip.setPixelColor(i,Wheel(map(i,0,strip.numPixels()-1,30,150)));
}
// Draw peak dot
if(peak > 0 && peak <= N_PIXELS-1) strip.setPixelColor(peak,Wheel(map(peak,0,strip.numPixels()-1,30,150)));
strip.show(); // Update strip
// Every few frames, make the peak pixel drop by 1:
if(++dotCount >= PEAK_FALL) { //fall rate
if(peak > 0) peak--;
dotCount = 0;
}
vol[volCount] = n; // Save sample for dynamic leveling
if(++volCount >= SAMPLES) volCount = 0; // Advance/rollover sample counter
// Get volume range of prior frames
minLvl = maxLvl = vol[0];
for(i=1; i<SAMPLES; i++) {
if(vol[i] < minLvl) minLvl = vol[i];
else if(vol[i] > maxLvl) maxLvl = vol[i];
}
// minLvl and maxLvl indicate the volume range over prior frames, used
// for vertically scaling the output graph (so it looks interesting
// regardless of volume level). If they're too close together though
// (e.g. at very low volume levels) the graph becomes super coarse
// and 'jumpy'...so keep some minimum distance between them (this
// also lets the graph go to zero when no sound is playing):
if((maxLvl - minLvl) < TOP) maxLvl = minLvl + TOP;
minLvlAvg = (minLvlAvg * 63 + minLvl) >> 6; // Dampen min/max levels
maxLvlAvg = (maxLvlAvg * 63 + maxLvl) >> 6; // (fake rolling average)
}
// Input a value 0 to 255 to get a color value.
// The colors are a transition r - g - b - back to r.
uint32_t Wheel(byte WheelPos) {
if (WheelPos < 128) {
// Red to magenta
return strip.Color(255, 0, WheelPos * 2);
} else {
// Magenta to purple
return strip.Color(255 - (WheelPos - 128) * 2, 0, 255);
}
}
Circuit Construction From Prototype to Soldered
Downloads
Form & Material
- Trim the LED strips to the appropriate size to ensure they fit within the outer casing.
- Solder each part(GND, 5V, A1) and connect them all together.
- Solder the connected LED strips with Gemma board and sound amplifier.
- Attach everything inside of the outer casing.
- Place the batteries into the battery pack and verify its functionality through testing.
Downloads
Celebrate and Call to Action
https://drive.google.com/file/d/1b0J80H7yXl5lyBAMUDXlnUuIZhlBik3v/view?usp=sharing