JamBot: Music Theory Aware Chord Based Generation of Polyphonic Music with LSTMs Gino Brunner, Yuyi Wang, Roger Wattenhofer, Jonas Wiesendanger Distributed Computing Group ETH Zurich Switzerland TexPoint fonts used in EMF. Read the TexPoint manual before you delete this box.: AAAAAAA

12 notes Black and white keys of piano G# A# C# C D E F G A H C D 12 notes Black and white keys of piano Same pitch interval between notes Notes names repeat

Scale Subset of the 12 Notes Defined by pitch intervals G A H C# D# F# G# A# C# D# F# G# A# C D E F G A H Scale Subset of the 12 Notes Defined by pitch intervals e.g. major scale: 2￫2￫1￫2￫2￫2￫1

Key root note + scale e.g., C major C D E F G A H C# D# F# G# A# C# D#

Key root note + scale e.g., C major C D E F G A H C# D# F# G# A# C# D#

C D E F G A H C# D# F# G# A# C# D# F# G# A# C D E F G A H Chord Subset of two or more (usually three) notes played at the same time e.g., C major

LSTMs (Long Short-Term Memory)

Dataset MIDI (Musical Instrument Digital Interface) format Like Sheet Music No Sound ~100’000 Songs

Scales of the Songs Only use songs in major scale Shift all songs to same root note

time pitch pitch time

Extract Chords 1. Histogram of notes over every bar

1. Histogram of notes over every bar

1. Histogram of notes over every bar 2. 3 most played notes form chord 3. Assign id to 50 most occurring chords

Input: Output: 10-dimensional chord embedding chord id embedded chord Output: Probability of every chord to be played in next bar

Input: Output: Probability of every note to be played in next timestep

Music Generation 1. 2. 3.

Midi Synthesizer

Chord Embeddings Circle of Fifths

Song 1 Instrument: Bright Acoustic Piano Tempo: 160 BPM

Song 2 Instrument: Electric Piano Tempo: 110 BPM

What’s Next? Instrumentation and Tempo Long Term Structure and Style Note Duration and Velocity

? JamBot TexPoint fonts used in EMF. Gino Brunner brunnegi@ethz.ch TexPoint fonts used in EMF. Read the TexPoint manual before you delete this box.: AAAAAAA