Claude Fable reverse-engineered a player piano’s secret MIDI

“I asked Claude to critique my piano. It stole the piano’s secret language.”

The Story

A builder asked Fable to compare Gymnopédie performances on a PianoDisc self-playing piano. The model decoded the vendor’s mp3 (right channel = MIDI on a 2004.5 Hz square wave, left = accompaniment), found “decoy notes” that obfuscate naive MIDI extraction, and wrote an encoder and decoder. The poster’s question: can they publish? Commenters flagged DMCA “effective technical measures.

Why It Matters

Perfect SFL triangle: art, builders, weird futures. An AI didn’t “make music”; it burglarized a 25-year-old player-piano DRM because someone asked it to care about rubato. Sacred objects: decoy notes, 2004.5 Hz. Distinct from generic coding-benchmark stories.

Evidence

Ask HN, ~187 pts / 112 comments, ~21h old.

Sources

Daily scan: 2026-09-07