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I want to make A L.E.D. Equalizer That is sound reactive, And I need some help in the design? Answered

I want to make something like this 

But have it be reactive to sound. And I just bought a arduino uno, And havent used it yet. Sounds like something that could be used/helpful. 

I have no idea where to start or what I would need.


This works for me somewhat.

Sound Operated VU Device.png

Did you check this one out?


It's not full color, but seems like a perfect project for Arduino.

thats pretty much what Im going for. But on a slightly larger scale.

What you need to create is a fast fourier transform of the input signal - that will "bin" the amplitude of each frequency in your signal and allow you to display it on LED bars.

Fortunately, the nasty bit, the FFT algorithm can be found here, and worked up on Arduino

My personal favourite after that, for, say 8 channels of LEDs with 8 levels of output, would be a MAX7221, like I used in my car-barduino project


O.O Well I have no experience. I just bought the arduino. And Im totally lost :/

I want to do this as my first legit project with it..

Any suggestions? Im still kinda lost. haha.

Its a biggie for a "first legit project"
Get to grips with it first - write "blinky" and put a 8 LEDs on the outputs, and try it with just measuring loudness..


Also. I had a idea. If you look up the "aurora 9 bar"

I could take maybe 10 of them, hook them all together, then to the arduino.

And have the lowest LED, be on. and when the music gets louder, and plays different frequencies the lights light up further.. just a thought.

Aurora bar uses the PIC not the arduino, but the principle is sound - all you have to do is write the program.

Well, could one use a arduino to control all of them persay?

Yes you could, but then its not the same system, and you can drive even more LEDs with an Arduino's pins

Alright. Sounds like a good start. Im gonna use my breadboard. When the board gets here. Set up 8 LED's and resistors and then which pin/ pins do I put it in on the arduino?

Any of the digital pins. You may like to use the PWM pins, and then you can play with the brightness too.

You want it to be FREQUENCY responsive as well as LOUDNESS responsive. There's a few instructables on it.

I can't view the video, but you are probably looking at a "color organ" or "light organ" and not an equalizer.

Well I basicly want to make a Box with a certain amount of led's. That are mounted in a fashion So they're in like rows of 10 going up and like 25 wide.
so 10 X 25. And when the sound is low/off only the bottom row of led's is on. but when I turn on music. they light up and fluctuate depending on the loudness / track it self.