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Pitch — A440 and the measured reference
music
Concert pitch fixes A above middle C at 440 Hz (MIDI note 69), sealed; the ensemble tunes to it under f = 440 * 2^((n-69)/12). Pitch is a measured frequency, and the interval arithmetic is sealed through the engine's music verifier.
source
Narrow Highway — music
card id
card_music_pitch
address
WIT.codex.FCT/pitch-a440-and-the-measured-reference/REF.WITNESSED@narrow-highway
adjoining cards
- part of → Music — interval, tuning, and the harmonic series — a pillar (Pitch)
- connects at → Metrology — measurement and the SI — A440 is a reference frequency - measurement
- connects at → The instruments — every verifier and validator, and where they join — the music verifier seals the interval and tuning arithmetic
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