As a musician myself, I was always fascinated by the mathematics behind the music. This work originated by the fact, that I always wanted to have a software that can turn my music into sheets. The bachelor thesis for my mathematics degree was the perfect opportunity to do exactly that. The Short Time Fourier Transformation (STFT) combined with a Sparsity Algorithm is a powerful tool to extract played notes and chords at given times. This thesis focuses on the analysis of this topic and presents an algorithm to turn .wav files into printable sheets.