An experiment of circular encoding
I am always fascinated by gramophones for their simplicity - a reading head, a speaker, and a rotating disk. Unfortunately, they are replaced by purely digital media of consumption, like computer files and online streaming. What if we bring back vinyl records but make them digital instead? This would make them more expressive and even programmable.
This project is a digital gramophone that reads data from a rotating disk encoded with data like drum beats and tones. The gramophone then plays the sound from the data using some predefined mapping. As the disk itself is replaceable and made by laser-cutting, users can make their own one easily and the process teaches them musical theories and encoding.
To make it possible, I laser-cut a disk encoded with the musical notes that I would like to play. As the disk rotates, a new row is read by the photoresistor array. If light passes through, it is a 1 and otherwise 0. There are 6 bits which allow 64 different notes. For example, 000000 is silence,100111 is D5 and 100000 is G4.
The circuit consists of a DC motor circuit and a photoresistor array.