MusicianCV · TRPure fourth
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Tuning and pitch systems
Pure fourth · 4:3 → 330 × 4/3 = 440 Hz
Fix a reference frequency before comparing tunings. An octave doubles frequency. Convert a frequency ratio to cents with 1200 × log₂(ratio).
Example
Read the ratio alongside the worked calculation. · 4:3 / 330 × 4/3 = 440 Hz
Read the ratio alongside the worked calculation.4:3 330 × 4/3 = 440 Hz
Try it
How does a frequency difference differ from a ratio?
Answer
Moving the same interval to another pitch preserves the ratio. The difference in hertz can change.Related topics
Twelve-tone equal temperamentReferences
Frequency and Pitch of Sound
Subject-expert review pending.