  We propose a novel approach for the generation of polyphonic music based on
LSTMs. We generate music in two steps. First, a chord LSTM predicts a chord
progression based on a chord embedding. A second LSTM then generates polyphonic
music from the predicted chord progression. The generated music sounds pleasing
and harmonic, with only few dissonant notes. It has clear long-term structure
that is similar to what a musician would play during a jam session. We show
that our approach is sensible from a music theory perspective by evaluating the
learned chord embeddings. Surprisingly, our simple model managed to extract the
circle of fifths, an important tool in music theory, from the dataset.
