I’ve been working on the lightbox, and ended up writing my own beat detection code. I wonder how far this will go?

Also, I’ve been having problems with interference on my soundcard coming from the USB line. Every time a large load is switched, a small “click” can be heard on the sound output. Chances are, the relays are causing EMI and that is traveling up the USB cable, through my motherboard, and messing with my soundcard. I’ve tried ferrite beads, that did no work. If anyone has ideas, please comment!

About 3 months ago, I had the most random idea — I wanted a real time music visualizer. However, I just didn’t have the time to do the research necessary for this project because of homework. Well, now that I am on spring break, I decided to make a reality. And it worked! The first time too!

There are two sides of this project, the hardware and the software. The hardware part was the easy part. Mike had an Arduino board laying around and I went to radioshack to buy a relay, a 9 volt battery, a diode, and a transistor. Thats basically all that is needed for the hardware side. I used the schematic found on http://www.glacialwanderer.com/hobbyrobotics/?p=9 to make sure I’m doing everything right. Putting this together only took about 2 hours.

The software side was a little bit more tricky. I tried two differently languages: MATLAB and C#. Both turned out to be quite a big failure. Then I stumbled upon Processing, which is basically an extension onto Java that made it easy for visual artists to create programs. Processing included a library called Minim, which had lots of built in features for audio analysis. I used the beat detection algorithm from Minim and then used that to send a signal to the Arduino board over USB to turn on or off the lights.

Basically thats all! Later I plan to find a better relay, something that lasts longer [solid state relay?], and then put it in a box so it is safer and looks better.

For now, enjoy the video!