A measurement of piano playing

Blur

How many changes of harmony are allowed to overlap under one pedal.

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

Jean Doyen — bars 5–6, blur 3.5 count10 s
Robert Casadesus, 1952 — bars 5–6, blur 3.6 count8 s

Most

Alice Sara Ott — bars 5–6, blur 10.9 count10 s
Beatrice Rana, 2013 — bars 5–6, blur 8.7 count9 s

How it is calculated

Mean number of bass-note changes caught inside a single pedal span.

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 C241.01.02.0
Mozart K. 545371.01.33.8
Chopin Étude 10/1311.21.71.9
Gymnopédie 1231.51.93.0
Träumerei311.72.12.7
Chopin Étude 10/12192.02.22.9
Schubert Op. 90/3431.72.32.8
Brahms Op. 118/2282.02.42.9
Fantaisie-Impromptu201.82.52.8
Pathétique II471.62.63.4
Ravel Pavane331.92.63.8
Schubert Op. 142/392.62.83.0
Clair de lune272.32.84.5
Rachmaninoff Prelude292.43.14.1
Chopin Ballade 4122.83.33.7
Nocturne Op. 9/2322.43.54.7
Nocturne Op. 48/1273.24.04.9
Ravel Ondine613.55.712.7

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 1.24. 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.