In music notation, a sixty-fourth note (North American), or hemidemisemiquaver or semidemisemiquaver (British), sometimes called a half-thirty-second note, is a note played for half the duration of a thirty-second note (or demisemiquaver), hence the name. It first occurs in the late 17th century and, apart from rare occurrences of hundred twenty-eighth notes (semihemidemisemiquavers) and two hundred fifty-sixth notes (demisemihemidemisemiquavers), it is the shortest value found in musical notation.
Sixty-fourth notes are notated with a filled-in oval notehead and a straight note stem with four flags. The stem is drawn to the left of the notehead going downward when the note is above or on the middle line of the staff. When the notehead is below the middle line the stem is drawn to the right of the notehead going upward. A single 64th note is always stemmed with flags, while two or more are usually beamed in groups.
A similar, but rarely encountered symbol is the sixty-fourth rest (or hemidemisemiquaver rest, shown in figure 1) which denotes silence for the same duration as a sixty-fourth note.
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- Haas, David. 2011. "Shostakovich’s Second Piano Sonata: A Composition Recital in Three Styles". In The Cambridge Companion to Shostakovich, edited by Pauline Fairclough and David Fanning, 95–114. Cambridge Companions to Music. Cambridge and New York: Cambridge University Press. ISBN 978-1-139-00195-3. doi:10.1017/CCOL9780521842204.006. "The listener is right to suspect a Baroque reference when a double-dotted rhythmic gesture and semihemidemisemiquaver triplets appear to ornament the theme" (112).
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