Turn (music)

In music, ornaments or embellishments are musical flourishes that are not necessary to carry the overall line of the melody (or harmony), but serve instead to decorate or "ornament" that line. Many ornaments are performed as "fast notes" around a central note. The amount of ornamentation in a piece of music can vary from quite extensive (it was often so in the Baroque period) to relatively little or even none. The word agrément is used specifically to indicate the French Baroque style of ornamentation.

In the baroque period, it was common for performers to improvise ornamentation on a given melodic line. A singer performing a da capo aria, for instance, would sing the melody relatively unornamented the first time, but decorate it with additional flourishes the second time.

Ornamentation may also be indicated by the composer. A number of standard ornaments (described below) are indicated with standard symbols in music notation, while other ornamentations may be appended to the score in small notes, or simply written out normally. Frequently, a composer will have his or her own vocabulary of ornaments, which will be explained in a preface, much like a code. A grace note is a note written in smaller type, with or without a slash through it, to indicate that its note value does not count as part of the total time value of the bar. Alternatively, the term may refer more generally to any of the small notes used to mark some other ornament (see Appoggiatura, below), or in association with some other ornament's indication (see Trill, below), regardless of the timing used in the execution.

In Spain, melodies ornamented upon repetition ("divisions") were called "diferencias", and can be traced back to 1538, when Luis de Narváez published the first collection of such music for the vihuela.

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