Tessitura
In music, tessitura (Italian: [tessiˈtuːra], texture; English /tɛsᵻˈtuːrə/) is the most musically acceptable and comfortable vocal range for a given singer or, less frequently, musical instrument; the range in which a given type of voice presents its best-sounding texture or timbre. This broad definition is often interpreted to refer specifically to the pitch range that most frequently occurs within a given piece, or part, of music. For example, throughout the entirety of Wagner's Ring, the music written for the role of Siegfried ranges from C♯3 to C5, but the tessitura is described as high because the phrases are most often in the range of C4 to A4.
In musical notation, tessitura refers to the compass in which a piece of music lies—whether high or low, etc.—for a particular vocal (or less often instrumental) part. The tessitura of a piece is not decided by the extremes of its range, but rather by which part of the range is most used. The tessitura of a part will often influence which clef a particular piece of music is written in. Melodic contour may also be considered to be an important aspect of vocal tessitura.
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