Digital LED Color Organ Test 1

This is something I put together that converts your computer's audio output into light.

I use Soundflower to redirect my audio out to Max MSP. Then I open iTunes and play a song. Max analyzes the incoming audio waveform and separates it into low, mid, and high range frequencies as well as stereo left and right. You can also adjust the gain on each range filter, adjust the volume on each channel, and adjust the peak frequencies of the low and high pass filters to fine tune to a particular song you might want to play. Max exports all this information to an Arduino sketch that routes the information to six pins on the Arduino board. I used six dim LEDs that I had laying around before I realized one of them wasn't working.

This is one of the first circuits I've ever built using Arduino and Max MSP. I had to troubleshoot a bit before I could get it to work. So you don't waste hours wondering why it doesn't work, unless you are using SparkFun's transistor based high-powered LED output, make sure you comment out or delete this line of code from the Arduino sketch:
"else { value = map(value,0,255,255,0); }"
It inverts the signal, making normal LEDs dim instead of glow when there is a sound. Also, make sure you install the messenger library in your Arduino sketchbook folder. Otherwise you should be golden.

I'm planning on building either a huge LED matrix or a high-intensity LED display to work with this setup. The small LEDs do not do this build justice.

If you're interested in making this or just want to learn more about it you can find the schematic, code, and full instructions here:
http://makeprojects.com/Project/Digital-LED-Color-Organ/424/1

You'll need an Arduino board (I used the Duemilanove) and Arduino software:
http://arduino.cc/en/

All of the other links to the remaining software you'll need will be found in the instructions I linked above. It helped to have some LEDs, wires, resistors, and a breadboard handy for assembling this very basic circuit and making connections to the Arduino.

Many thanks to Collin Cunningham from MAKE for coding and guiding me in making this beautiful thing!

Category:

Howto & Style

Tags:

• digital
• led
• color
• organ
• Soundflower
• Max MSP
• MAKE
• low pass filter
• high pass filter
• Arduino
• Collin Cunningham
• Circuit Skills
• Zack Szabadi