This thesis explores several visualizations that aim to assist aspiring drummers with learning the drums using projector-based augmented reality technology. It aims to provide feedback on their training sessions when they do not have a professional teacher available. This feedback is projected directly onto the instrument, so the user does not have to transfer the information from e.g. a screen to their drums and can save cognitive resources. We give feedback in real-time and retrospectively. For the real-time feedback, we have to consider a visualization that keeps the information lightweight, to not divert too much attention away from playing the instrument, so we use simple encodings like color or a speedometer. For retrospective feedback, we use more complex visualizations like a pie chart. Our approach can give feedback on timing and dynamics of the played pattern. We evaluated our visualizations with three case studies, one that focuses on comparing the different visualizations, one that evaluates their efficiency in identifying errors, and one that investigates the influence of the visualization regarding errors made over time. We conclude that the visualizations help the user identify their errors, however, we did not have enough data to truly verify that they reduce errors in one's performance over time, or if one visualization has a better performance than the others.