Portamento

In music, portamento (plural: portamenti, from Italian: portamento, meaning "carriage" or "carrying") is a pitch sliding from one note to another. The term originated from the Italian expression "portamento della voce" (carriage of the voice), denoting from the beginning of the 17th century its use in vocal performances and its emulation by members of the violin family and certain wind instruments, and is sometimes used interchangeably with anticipation. It is also applied to one type of glissando as well as to the "glide" function of synthesizers.

In the first example, Rodolfo's first aria in La Sonnambula (1831), the portamento is indicated by the slur between the third and fourth notes. The second example, Judit's first line in Duke Bluebeard's Castle (1912), employs a short, straight line between the fourth and fifth notes to indicate a steady rise in pitch. If the composer desired the pitches to be, variously, raised and lowered between those two notes, the wavy line would additionally be curvy, conveying an approximation of the pitches intended. Portamento may, of course, also be used for descending intervals.

In the performance of Italian bel canto music, the concept of the musical slur and that of the true portamento have not always been held to mean the same thing. This is explained simply by Nicola Vaccai in his Practical Method of Italian Singing, originally published 1832, whose opinion in the matter holds some authority. In the sense described by Vaccai, the portamento is not a slur but an ornamental accentuation of the legato linking two distinct notes, without any slide or glide through the intervening notes. In his own opening statements forming the preface to his Lesson XIII, "Modo per portare la voce" (method to carry the voice), Vaccai states: "By carrying the voice from one note to another, it is not meant that you should drag or drawl the voice through all the intermediate intervals, an abuse that is frequently committed—but it means, to 'unite' perfectly the one note with the other." He goes on to describe and illustrate that where a consonant falls between the two notes to be ligatured in this way, the portamento is achieved either by "almost insensibly" anticipating the second note of a pair in the final moments of the vowel sound preceding it, or else by minutely deferring the "salto" or leap between the notes until the first moment of the vowel sound in the second note. He adds, "In phrases requiring much grace and expression, it produces a very good effect: the abuse of it, however, is to be carefully avoided, as it leads to mannerism and monotony."

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