Liquid Concerto is an installation project using chemical solutions from physical world to visualize music from the virtual world.
I used minim library in Processing to analyze the music. Processing sends the beats data to a device powered by Arduino, which controls the servo motors in pistol mechanism. The pistol mechanism pushes syringe via servo motor. There are two devices like this above each glass tube. You can see the setup here. One device's syringe contains acid solution, another's contains base solution. By dropping base solution into tube, it changes the phenolphthalein indicator solution into pink. Right after, the same amount of acid is dropped to change the solution back to neutral which helps the tube remains transparent.
In this demo video, I used music "Botellas vacías, botellas llenas" from artist Bosques de mi Mente. The artist kindly separated the music into two tracks for this project, one by cello another by violin. Each track operates two devices independently.