We describe the concepts behind a web-based minimal-UI DJ system that adapts to the user’s preference via sim- ple interactive decisions and feedback on taste. Starting from a preset decision tree modeled on common DJ prac- tice, the system can gradually learn a more customised and user-specific tree. At the core of the system are structural representations of the musical content based on semantic au- dio technologies and inferred from features extracted from the audio directly in the browser. These representations are gradually combined into a representation of the mix which could then be saved and shared with other users. We show how different types of transitions can be modeled using sim- ple musical constraints. Potential applications of the system include crowd-sourced data collection, both on temporally aligned playlisting and musical preference
