ostinati or riffs Harmonic accompaniment is music played to accompany a melody line; it is usually chordal and played by such instruments as (acoustic or electric) guitar, piano, organ and bass guitar, but it can also be played by instruments that ordinarily play the melody, such as the violin. In most tonal music the melody and accompaniment are written from and share the same group of pitches, while in much atonal music the melody and accompaniment are chosen from entirely separate groups of pitches, often from different hexachords. See also: chord-based.
An accompanist is one who plays an accompaniment. A number of classical pianists have become famous as accompanists rather than soloists; the best known example is probably Gerald Moore, well known as a Lieder accompanist.
Notated accompaniment may be indicated obbligato (obliged) or ad libitum (at one's pleasure).
Dialogue accompaniment is a form of call and response in which the lead and accompaniment alternate, the accompaniment playing during the rests of the lead and providing a drone or silence during the main melody or vocal. (van der Merwe 1989, p.320)
Basso continuo is a form of notation used especially in Baroque music accompaniment parts.
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