It's Time for a Song - Transcribing Recordings of Bell-playing Clocks

The paper presents an algorithm for automatic transcription of recordings of bell-playing clocks. Bell-playing clocks are clocks containing a hidden bell-playing mechanism that is periodically activated to play a melody. Clocks from the eighteenth century give us unique insight into the musical taste of their owners, so we are interested in studying their repertoire and performances thus the need for automatic transcription. In the paper, we first present an analysis of acoustical properties of bells found in bell-playing clocks. We propose a model that describes positions of bell partials and an algorithm that discovers the number of bells and positions of their partials in a given recording. To transcribe a recording, we developed a probabilistic method that maximizes the joint probability of a note sequence given the recording and positions of bell partials. Finally, we evaluate our algorithms on a set of recordings of bell-playing clocks.