Portamento is a musical term currently used to mean pitch bending or sliding, and in 16th century polyphonic writing refers to a type of musical ornamentation.

Pitch bending

In current usage, portamento is making a continuous "slide" up or down in frequency from a previous note, rather than a discrete change from one note to the next. This is most commonly encountered on string instruments, such as the guitar or violin, which can produce a continuous range of frequencies rather than being limited to the chromatic or diatonic scale, and impossible on a fixed-pitch instrument like the piano. The trombone also produces quite effective portamento (referred to as a "smear"), as would any instrument with a slide, such as the slide whistle. Other wind instruments have a very limited capability to produce this effect, and can portamento through only as wide a pitch range as can be affected by embouchure alone, which is often not more than a step. Machine timpani are unusual among percussion instruments in being able to be played whilst being tuned, allowing for portamento effects (often wrongly called "glissando" in this context).

The human voice is easily capable of portamento: however, this is often regarded as a defect in singing style ("missing the note"), rather than a deliberate feature of vocal music (a "vocal swoop").

Portamento can often be generated automatically on synthesizers, where a parameter setting can be used to control the speed at which an oscillator moves to a new pitch. Often this parameter is called glide. Alternatively, portamento effects can be produced manually by a skilled player by the use of the pitch wheel at the side of most synthesizer keyboards. Synth lines with lots of portamento defined West Coast G funk of the mid 1990s, and continue to be a distinctive part of electronic music today.

In MIDI sequencing, portamento can be generated by using a channel message that creates a sliding effect by smoothly changing pitch from the last note played to the pitch of the currently playing note.

Ornamentation

In 16th century style, portamento is an anticipation figure, occurring on the off-beat of strong beats in the music (beats 1 and 3). The portamento resolves stepwise, almost always downward. It may occur either once or multiple times in succession.

In multi-voice polyphony, the portamento figure is normally consonant. This embellishment is frequently found ornamenting suspensions, though almost never at the final cadence.

See also

• A glissando is a similar effect to portamento which moves in discrete steps; for example, dragging a finger over the keys of the piano.
• Vibrato is a repetitive smooth change in pitch that occurs in rapid cycles.

Citations

• Gauldin, Robert (1985). A Practical Approach to Sixteenth-Century Counterpoint. Long Grove, IL: Waveland Press