  We present a new system for simultaneous estimation of keys, chords, and bass
notes from music audio. It makes use of a novel chromagram representation of
audio that takes perception of loudness into account. Furthermore, it is fully
based on machine learning (instead of expert knowledge), such that it is
potentially applicable to a wider range of genres as long as training data is
available. As compared to other models, the proposed system is fast and memory
efficient, while achieving state-of-the-art performance.
