Comparing Approaches to the Similarity of Musical Chord Sequences

We present an comparison between two recent approaches to the harmonic similarity of musical chords sequences. In contrast to earlier work, that mainly focuses on the similarity of musical scores or musical audio, in this paper we specifically use on the symbolic chord description as the primary musical representation and the similarity between sequences of these descriptions. In an experiment we compare a geometrical and an alignment approach to harmonic similarity, and measure the effects of chord description detail and a priori key information on retrieval performance. For this experiment a large new chord sequence corpus is assembled. The results show that a computational costly alignment approach significantly outperforms a much faster geometrical approach in most cases, that a priori key information boosts retrieval performance, and that using a triadic chord representation yields significantly better results than using more simple or more complex chord representations.