semitone

musical measurement

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July 13, 2026

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A semitone, also known as a half step or half tone, is the smallest interval commonly used in Western music. It represents the distance between two adjacent keys on a piano, such as from G to G-sharp or E to E-flat. An octave, spanning from one note to the next of the same name (e.g., G to the next G), contains twelve semitones. Two semitones together form a whole tone. In music theory, intervals are measured by the distance between two tones, and a semitone is a fundamental unit for defining these distances. Music that uses intervals smaller than a standard semitone is referred to as microtonal music.12345

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microtonal music
…that differ from the standard semitones (half steps) of a tuning system or scale. In the division of the octave established by the tuning system used on the piano, equal temperament, the smallest interval (e.g., between B and C, F and F♯, A♭ and A) is the semitone, an interval…
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…that differ from the standard semitones (half steps) of a tuning system or scale. In the division of the octave established by the tuning system used on the piano, equal temperament, the smallest interval (e.g., between B and C, F and F♯, A♭ and A) is the semitone, an interval…
Read More

scale
Common scale types
Microtonal scales, requiring intervals smaller than the conventional half step, also appeared sporadically in the 20th century. Among microtonal structures, the most important, perhaps, have been scales calling for quarter tones (equal to half the distance of a half step).
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Microtonal scales, requiring intervals smaller than the conventional half step, also appeared sporadically in the 20th century. Among microtonal structures, the most important, perhaps, have been scales calling for quarter tones (equal to half the distance of a half step).
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musical sound
Division of the pitch spectrum
…into 12 equal half-steps, or semitones, this method provides precisely equal intervals and a full set of chords that, although not as euphonious as those of the overtone series, are not offensive to the listener.
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…into 12 equal half-steps, or semitones, this method provides precisely equal intervals and a full set of chords that, although not as euphonious as those of the overtone series, are not offensive to the listener.
Read More