Unfigured bass

Unfigured bass, less commonly known as under-figured bass, is a kind of musical notation used during the Baroque music era in Western Classical music (ca. 1600–1750) in which a basso continuo performer playing a chordal instrument (e.g., harpsichord, organ, or lute) improvises a chordal accompaniment from a notated bass line which lacks the guidance of figures indicating which harmonies should be played above the bass note (see figured bass). Figured bass parts have numbers or accidentals below the bass line which indicate which intervals above the bass should be played in the chord. However, not all basso continuo parts from the Baroque period were figured.

From the earliest days of thoroughbass, composers and copyists have been chastised for providing bass parts without any figures to guide performers. Despite perennial complaints, however, unfigured basses persisted right through the eighteenth century. Though it is speculated that unfigured basses would not have existed if it were not for the suggestion of harmonies in bass lines of the time.

In the early baroque period published parts were as likely to be unfigured as figured, leading to unusual clashes of harmony on a first reading. In an effort to perform a piece the first time without such harmonic clashes, various methods were devised and used to anticipate the harmonic structure and progression of a piece. Among these are:

Even in a figured bass part, not all bass notes were necessarily figured. By convention, bass notes which are the root note of a root-position chord were often left unfigured. In an otherwise figured part, an unfigured bass note was understood to be the equivalent of having 5
3 written below it, calling for a root-position triad.

Many music masters in the Baroque period educated students in the art of playing unfigured bass accompaniment fluently. Many pieces such as Partimenti were written for this purpose.

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