Automatic Light Show

Growing up I came to love all things that lit up, and Christmas lights were no exception. So when my Dad brought home some GE Color Effects G-35 lights, I was thrilled. Since their release years ago there have been quite a few hacks featuring these bulbs in creating awesome displays, and I wanted to try one as well.

The vision that I had in my mind was a light show that you adapted to any song or audio source in real time. While you can create some amazing timed displays, I decided on focusing on real time displays.

Using the popular MSGEQ7 IC chip, I was able to construct a circuit that would take in an aux input and create a state vector of 7 different spectrums of noise, sampled at about 33 hertz. In other words, I’m getting almost 2,000 data points per minute of music on the frequency of different audio spectrums.

With this data I would estimate the 7 derivatives for each channel, and use that to determine the brightness for each lightbulb. This essentially would dim or brighten the lights with the music. To determine cutoffs for the minimum and maximum brightness, I used a simple low pass filter.

If I were to continue the project, I would use either a moving average or an ARIMA model to better determine cutoffs for when the lights should be off or at full brightness. This would lead to much better performance in all genres of music and any additional audio sources.