Reviving an Old LED Screen: From Dust to Drum Visualizer


A few years ago, I built a large LED screen out of empty toilet paper rolls. It was a fun DIY project controlled by an Android app, and I even wrote an article about it. But after some time, the screen ended up unused, just sitting around collecting dust. When I recently decided to check it out, I found that some of the LEDs were no longer working. I was ready to toss it out, but then an idea hit me.

The Drum Set and the Spark of an Idea

Last Christmas, we welcomed a new addition to our home—a drum set (Alesis Drums Nitro Mesh Kit). While setting it up and exploring its features, I noticed that it supported MIDI output, and I realized that my old LED screen could be repurposed as a visualizer for the drum set. This would not only breathe new life into the screen but also enhance the drumming experience with dynamic light displays.

Upgrading the LED Screen

The first step was to replace the non-functioning LEDs. I decided to upgrade to RGB LEDs this time, allowing for a broader range of colors and more dynamic visuals. I also needed a proper adapter to power the LEDs and ensure they worked smoothly with the new setup.

The Coding Challenge: Arduino vs. Raspberry Pi

Initially, I wrote the code for an Arduino. However, I quickly encountered a problem: Arduino’s single-threaded nature couldn’t handle multiple simultaneous drum hits. When two drums were struck at the same time, the Arduino would skip notes, resulting in a not satisfying visual experience.

Realizing the need for multitasking, I switched to a Raspberry Pi (RPI). With its support for multithreading, the Raspberry Pi could handle simultaneous drum hits without any issues. I wrote the new code with two threads in mind: one for reading MIDI signals into a queue and another for handling the visualizations.

Designing the Visualization

When it came to designing the visualization, I experimented with a few different styles. The goal was to discover a design that was not only visually striking but also accurately reflected the intensity of each drum hit. I opted for vertical columns that rise higher based on the strength of the drum hit. Each drum triggers a different color, creating a rhythmic light show that perfectly complements the music.

The Final Result

The final result is a repurposed LED screen that now serves as a stunning visualizer for our drum set. Every time we play, the screen lights up in sync with the beats, adding a whole new dimension to the drumming experience.

This project reminded me of the importance of not giving up on old creations. Sometimes, all it takes is a little creativity and a willingness to experiment to turn something old and forgotten into something new and exciting. So, if you have an old project gathering dust, take another look—it might just spark your next big idea.








You can find the source code here: https://github.com/mbodis/toilet-drum-set-rpi

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