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Musical texture, by the numbers

By Mayank Sanganeria

Every bar of piano music is doing one of a few basic things: carrying a tune over an accompaniment, running a single figure with no separate melody on top, or stacking full chords and moving them together. Our reduction pipeline tags each window it processes with one of exactly three textures, and across our corpus (54 pieces, including all 36 WTC preludes) it tagged 4802 of them: 33.4% pure figuration, 33.7% melody over figuration, and 32.9% chordal — a near three-way split, with no single texture dominating real piano writing.

Practice with the pieces that use it →

The census

Worth being precise about what this does and doesn't measure: the classifier sorts by density and role — is there a clear tune riding over an accompaniment, is the accompaniment the whole texture, or is it all moving in block chords — not by how many independent melodic lines are actually present. A Bach two-part invention gets tagged pure figuration or melody over figuration bar by bar just like a Chopin nocturne, even though what's happening underneath is genuinely contrapuntal, two hands trading independent lines. These three labels describe the reduced surface, not the voice-leading underneath it.

Hear the shifts

Each link opens the piece in the harmony player — the bar numbers below show where the texture changes inside that piece.

• Invention No. 1 in C, BWV 772 J. S. Bach bar 1: pure figuration · bar 12: melody over figuration · bar 23: chordal
• Sonatina in G, Anh. 5 No. 1 L. v. Beethoven bar 1: melody over figuration · bar 9: pure figuration · bar 32: chordal
• Canon in D J. Pachelbel bar 1: pure figuration · bar 5: melody over figuration · bar 81: chordal
• Nocturne in C-sharp minor (Op. posth.) F. Chopin bar 1: chordal · bar 5: melody over figuration · bar 23: pure figuration
• Nocturne in E♭, Op. 9 No. 2 F. Chopin bar 0: chordal · bar 2: pure figuration · bar 3: melody over figuration
• Sonatina in C, Op. 36 No. 1 M. Clementi bar 1: melody over figuration · bar 9: pure figuration · bar 30: chordal
• Air Napolitain "Santa Lucia" C. Czerny bar 1: pure figuration · bar 2: melody over figuration · bar 24: chordal
• Waltz, Op. 32 No. 1 C. Czerny bar 2: pure figuration · bar 3: melody over figuration · bar 9: chordal
• Arabesque No. 1 C. Debussy bar 1: melody over figuration · bar 1: pure figuration · bar 32: chordal
• Arabesque No. 2 C. Debussy bar 1: chordal · bar 19: pure figuration · bar 20: melody over figuration
• Clair de Lune C. Debussy bar 1: chordal · bar 3: melody over figuration · bar 27: pure figuration
• Humoresque No. 7 A. Dvořák bar 1: melody over figuration · bar 2: pure figuration · bar 7: chordal

Go deeper

• Train your ear to catch it → Our ear-training site drills telling the three textures apart by ear alone, no score in front of you.
• The theory: texture → Monophonic, homophonic, polyphonic — the vocabulary behind what our classifier is measuring, on our theory site.
• What the reduction throws away → Texture classification and non-chord-tone filtering are two sides of the same reduction — one decides what role a note plays, the other decides whether it belongs to the chord at all.
• Learn a piece that uses them → The practice ladder loops eight bars at a time — hear the harmony slowly, read along, then play at tempo.