A measurement of piano playing

Melody roughness

The opposite view of the same thing: note-to-note jumps in melody loudness.

What it sounds like

The same passage — Ravel Ondine, bars 5–6 — from the recordings that sit lowest and highest on this measurement. Every clip is a note list replayed on one sampled grand at one gain, so the only difference you are hearing is the playing.

Least

Werner Haas, 1965 — bars 5–6, melody roughness 7.1 vel8 s
Ivo Pogorelich, 1983 — bars 5–6, melody roughness 7.5 vel10 s

Most

Roger Muraro, 2003 — bars 5–6, melody roughness 11.7 vel10 s
Philippe Bianconi, 2023 — bars 5–6, melody roughness 9.9 vel10 s

How it is calculated

Mean absolute difference in velocity between consecutive melody notes.

How much pianists differ on it

Every piece in the library, with the range across its recordings. The units mean the same thing in every row, except for basic tempo, which is in each piece’s own beat.

PieceRecordingsLowestMedianHighest
Bach Prelude in C273.85.28.4
Mozart K. 545374.75.87.1
Nocturne Op. 9/2325.46.48.8
Fantaisie-Impromptu205.76.88.1
Brahms Op. 118/2285.96.87.9
Schubert Op. 90/3435.86.99.9
Chopin Ballade 4126.27.08.4
Pathétique II475.67.010.2
Rachmaninoff Prelude295.47.010.7
Gymnopédie 1236.07.19.3
Schubert Op. 142/395.87.48.0
Clair de lune276.07.49.7
Träumerei315.17.69.4
Nocturne Op. 48/1276.47.910.0
Chopin Étude 10/12196.08.210.4
Chopin Étude 10/1316.58.510.7
Ravel Pavane336.08.510.6
Ravel Ondine617.19.413.3

How reliably it can be measured

A Disklavier capture — the pianist’s own key sensors, no microphone — was rendered to audio, transcribed as if it were a recording, and re-measured. The error the transcription step introduces, as a multiple of how far pianists actually differ on this dial, is 1.07. noisy The transcription moves this dial about as far as pianists differ on it, so no claim should rest on where a single recording sits.