Sustained tone
A long-held, sustained note.
What it means
A sustained tone is a note that is held over a longer stretch of time while the other voices move. It thereby forms a fixed point within a changing texture. Depending on register and function it carries different names: if it lies in the bass and stays put through changing harmonies, one speaks of a pedal point; if it lies in a middle or upper voice, one speaks rather of the sustained tone or held note.
In the notation
It is written as a long note value or as a sequence of tied notes, often spanning several bars. In scores it is easily overlooked, because little notation stands at that point; precisely for that reason it rewards attention when reading — what does not move holds the texture together.
Musical use
The effect rests on the contrast between standstill and movement. If a note stays held while the harmony changes, shifting frictions arise: the same note is at one moment a chord tone, then a dissonance, then a chord tone again. On this principle rest the pedal point, which builds up tension before a close, and the drone, which gives a whole piece of music an immovable foundation. The suspension, too, is at its core a sustained tone: one voice stays while the others move on, and resolves belatedly.
In the polyphonic writing of older periods, the cantus firmus fulfils a similar role by leading a given melody in large values beneath moving voices.
Sustained tones occur in many genres: as a drone in folk music, as a pedal point in the bass, as a held middle voice in orchestral movements, or as a pad sound in electronic music. They create a calm background against which other voices move. A sustained tone in an upper voice is also called a pedal point in the upper voice.
Performance practice
Keep a sustained tone alive: a note that simply stands still loses tension and intonation. For wind and string players, even leading decides it; for singers, breath support. Listen to what happens around you, and adjust your intonation to the changing harmonies — the same note requires slightly different pitch in different sonorities. And pull back dynamically when the movement lies with others.