Note value

In music notation, a note value indicates the relative duration of a note, using the color or shape of the note head, the presence or absence of a stem, and the presence or absence of flags/beams/hooks/tails.

A rest indicates a silence of an equivalent duration.

The breve appears in several different versions, as shown at right. The first two are commonly used; the third is a stylistic alternative.

Sometimes the longa or breve is used to indicate a very long note of indefinite duration, as at the end of a piece (e.g. at the end of Mozart's Mass KV 192).

When a stem is present, it can go either up (from the right side of the note head) or down (from the left side), except in the cases of the longa or maxima which are nearly always written with downward stems. In most cases, the stem goes down if the notehead is on the center line or above, and up otherwise. Any flags always go to the right of the stem.

A note value may be augmented by adding a dot after it. This dot adds the next briefer note value, making it one and a half times its original duration. A number of dots (n) lengthen the note value by 2ⁿ − 1/2ⁿ its value, so two dots add two lower note values, making a total of one and three quarters times its original duration. The rare three dots make it one and seven eighths the duration, and so on.

The double dot was first used in 1752 by J.J. Quantz; in music of the 18th century and earlier the amount by which the dot augmented the note varied: it could be more or less than the modern interpretation, to fit into the context.

To divide a note value to three equal parts, or some other value than two, tuplets may be used. However, see swung note and notes inégales.

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