Listen
The same twelve chorales — Bach's BWV 253 through 264 — rendered again and again under different tunings and different settings. 10 albums, 120 recordings.
Just intonation
Chords tuned to whole-number frequency ratios drawn from a tonality diamond, found by simulated annealing and then threaded together with Viterbi optimisation. These are successive passes at the same idea, newest first — each refines the tuning search and the orchestration over the one before it.
- August 2026
The current rendering — the one the daily post draws from.
- Late July 2026
- Early July 2026
- July 2026
- Late June 2026
- Short Repeats
A structural variant of the late-June pass, with the repeats shortened.
- June 2026
The first full pass in just intonation.
Werckmeister III
A well temperament from 1691, contemporary with Bach. Keys retain distinct character rather than sounding identical.
- Werckmeister III
The same twelve chorales in the well temperament of Bach's own era — a reference point between equal temperament and just intonation.
12-tone equal temperament
The modern standard: the octave split into twelve identical steps. Every key is equally usable and no chord is perfectly in tune.
- 12-Tone Equal Temperament
The control. The same twelve chorales in the tuning of every modern piano, for direct comparison.
Early experiments
The first renders, made before the density control existed — they use the legacy max-shift setting and much slower tempos. Kept for reference; superseded by the just-intonation passes above.
- Early Experiments
The first attempts, at markedly slower tempos.