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The Physics of musical sounds

On the equally tempered scale the frequency ratio for each semitone is 1.0595:1. The ratio for the tone interval is the sixth root of 2 and that for the semitone the twelfth root of 2.

If the pitch of a note is increased by an octave the frequency is doubled.

Note C D E F G A B C'
Frequency (Hz) 262 295 328 349 393 440 491 524
Ratio (f/fC 1 9/8 5/4 4/3 3/2 5/3 15/8 2

 
 
 
© Keith Gibbs 2011