Sixty-fourth note twenty-eighth note—otherwise known as the "semihemidemisemiquaver" —and even shorter notes, are occasionally found. Sixty-fourth note In music notation, a sixty-fourth note (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 note head and a straight note stem with
Musical note number (and 69 is the number of semitones between C (note 0) and A). And in the opposite direction, to obtain the frequency from a MIDI note "p", the formula is defined as: For notes in an A440 equal temperament, this formula delivers the standard MIDI note number ("p"). Any other frequencies fill the space between the whole numbers evenly. This lets MIDI instruments be tuned accurately in any microtuning scale, including non-western traditional tunings. Music notation systems have used letters of the alphabet for centuries. The 6th-century philosopher Boethius is known to have used the first fourteen letters of