A measurement of piano playing
Whether a player presses on into a contrasting section or draws back.
The same passage — Nocturne Op. 48/1, bars 49–51 — 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.
log2 of the tempo of one section divided by another, chosen per piece.
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 |
|---|---|---|---|---|
| Nocturne Op. 9/2 | 32 | -0.35 | -0.10 | 0.22 |
| Chopin Étude 10/1 | 31 | -0.08 | -0.05 | 0.04 |
| Schubert Op. 90/3 | 43 | -0.16 | -0.03 | 0.09 |
| Gymnopédie 1 | 23 | -0.07 | -0.02 | 0.03 |
| Bach Prelude in C | 27 | -0.09 | -0.02 | 0.05 |
| Mozart K. 545 | 37 | -0.10 | -0.01 | 0.06 |
| Ravel Pavane | 33 | -0.49 | 0.00 | 0.28 |
| Brahms Op. 118/2 | 28 | -0.29 | 0.06 | 0.31 |
| Träumerei | 31 | -0.24 | 0.09 | 0.39 |
| Pathétique II | 47 | -0.07 | 0.14 | 0.42 |
| Chopin Étude 10/12 | 19 | 0.05 | 0.17 | 0.32 |
| Ravel Ondine | 61 | 0.01 | 0.28 | 0.56 |
| Chopin Ballade 4 | 12 | 0.34 | 0.47 | 0.88 |
| Nocturne Op. 48/1 | 27 | 0.16 | 0.48 | 1.02 |
| Clair de lune | 27 | 0.19 | 0.51 | 1.04 |
| Schubert Op. 142/3 | 9 | 0.66 | 0.75 | 0.95 |
| Fantaisie-Impromptu | 20 | 0.82 | 1.10 | 1.32 |
| Rachmaninoff Prelude | 29 | 2.23 | 2.55 | 3.20 |
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 0.07. solid This dial survives transcription intact: where one recording sits on it can be argued from.