Pitch · standard
A=440 Hz: how modern concert pitch won
A4 = 440 HzHistory of concert pitch standardization, ISO 16, and why 440 is convention — not cosmic law or conspiracy proof.
◈ Science
A4 = 440 Hz is an international reference frequency for musical pitch (ISO 16). It does not define “correct” timbre, emotion, or biology. Orchestras still vary slightly (often 441–443) for brilliance.
Equal temperament divides the octave into 12 equal logarithmic steps; once A is fixed, other notes follow. Baroque pitch (often ~415) and classical chamber pitch differ because standards change with culture, not because Earth changed spin.
✦ Mystic / Mythos
Anti-440 lore claims Rockefeller, Nazis, or Tavistock “imposed” 440 to agitate populations. Primary-source history is messier: competing national pitches, instrument makers, military bands, and broadcasting convenience. Treat viral weaponization stories as modern myth unless you can cite primary documents carefully.
History timeline
- 19th c. France and others push lower “diapason normal” (often 435).
- Early 20th c. US/UK discussions drift toward 440 for instrument and broadcast consistency.
- 1939 international conference preference for 440; postwar practice solidifies.
- ISO 16 formalizes 440; digital tuners and sample libraries cement it globally.