A measurement of piano playing
How evenly the notes between the beats are spaced — the fine grain of the pulse.
The same passage — Chopin Étude 10/12, bars 11–14 — 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.
Standard deviation of where off-beat eighths actually fall, relative to a straight line drawn between the surrounding beat times, as a percentage of the beat.
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.
| Piece | Recordings | Lowest | Median | Highest |
|---|---|---|---|---|
| Bach Prelude in C | 27 | 1.8 | 3.0 | 26.5 |
| Pathétique II | 47 | 2.3 | 3.5 | 5.3 |
| Schubert Op. 142/3 | 9 | 4.5 | 4.9 | 9.8 |
| Mozart K. 545 | 37 | 4.3 | 6.0 | 10.7 |
| Nocturne Op. 9/2 | 32 | 4.6 | 6.3 | 8.7 |
| Chopin Étude 10/1 | 31 | 4.6 | 6.8 | 12.7 |
| Chopin Ballade 4 | 12 | 6.4 | 7.0 | 11.2 |
| Brahms Op. 118/2 | 28 | 4.0 | 7.1 | 12.1 |
| Rachmaninoff Prelude | 29 | 5.0 | 7.6 | 18.1 |
| Clair de lune | 27 | 5.3 | 8.2 | 12.3 |
| Ravel Pavane | 33 | 5.2 | 8.5 | 11.7 |
| Träumerei | 31 | 5.1 | 9.2 | 17.8 |
| Nocturne Op. 48/1 | 27 | 7.8 | 9.6 | 14.4 |
| Chopin Étude 10/12 | 19 | 6.2 | 9.8 | 12.1 |
| Schubert Op. 90/3 | 43 | 7.4 | 9.9 | 14.7 |
| Ravel Ondine | 61 | 7.9 | 10.2 | 15.6 |
| Fantaisie-Impromptu | 20 | 7.3 | 10.8 | 18.8 |
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 1.00. 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.