Figured Bass

Overview

Figured bass, also known as thoroughbass, is a shorthand notation used primarily in the Baroque era to convey harmonic information to a continuo player. A bass line is written on the staff, and numbers (figures) are placed beneath it to indicate intervals above the bass note, thereby specifying the chord that should be realized. The system allows a single written part to imply an entire harmonic texture, which is then improvised by a keyboardist, lutenist, or other chordal instrument.

The practice of realizing figured bass was central to ensembles of the 17th and early 18th centuries, providing flexibility and a degree of improvisatory freedom while ensuring harmonic coherence. Modern scholars and performers study figured bass to understand historical performance practice and to recreate authentic Baroque sounds.

How It’s Notated

Figures are written directly below the corresponding bass note, usually aligned with the notehead. Numbers indicate the interval above the bass (e.g., “6” signals a sixth above, often implying a first‑inversion triad). Accidentals placed before a figure alter that specific interval (e.g., “♭6” lowers the sixth). When a figure is omitted, the default is a root‑position triad (a “5 3” or simply “” meaning “5 3”). Slashes may be used to indicate diminution of note values, and a horizontal line (a tie) can extend a figure over multiple notes. Placement exceptions include stacked figures for compound intervals (e.g., “4/2” for a fourth plus a second) and the use of parentheses to suggest optional or editorial additions.

How It’s Performed

A continuo player reads the bass line and its figures, then constructs the appropriate chord by adding the indicated intervals above the bass note. Realization involves choosing chord voicings, inversions, and appropriate ornamental figures (such as passing tones or suspensions) that suit the style and texture of the piece. Keyboard players typically use the left hand for the bass note and the right hand for chordal elaboration, while lute or theorbo players pluck the indicated notes. The performer must also be aware of the harmonic context, adjusting dissonances and resolutions according to Baroque conventions.

Origin

The system emerged in early 17th‑century Italy, building on earlier organum and chant accompaniment practices. Girolamo Diruta’s treatise “Il Transilvano” (1593) contains one of the first systematic explanations of the method. By the mid‑Baroque, figured bass had become standard in Italy, France, Germany, and England, appearing in the works of composers such as Corelli, Bach, and Handel.

Where You’ll See It

Figured bass is most common in Baroque scores, especially in orchestral and chamber works that include a continuo group (harpsichord, organ, lute, theorbo, or violone). It also appears in sacred music, operas, and solo sonatas of the period. The notation is less frequent after the Classical era, giving way to fully written chordal parts. For broader context, see Silo 7 (Music History & Eras) and Silo 4 (Genres).

Common Misconceptions / Confused Symbols

Because Figured Bass shares visual elements with other notational systems, learners often confuse it with related symbols.

• Misconception: A blank space means no harmony.
  Correction: In Figured Bass, a blank space usually denotes a root‑position triad (5‑3) unless the context specifies otherwise.
• Misconception: Figured bass numbers are the same as Roman‑numeral analysis.
  Correction: Figured bass numbers indicate intervals above the bass note, while Roman numerals label scale degrees relative to a tonic.
• Misconception: Accidentals before a figure affect the bass note.
  Correction: Accidentals modify the specific interval indicated by the figure, not the bass note itself.
• Misconception: Figured bass is identical to modern lead‑sheet chord symbols.
  Correction: Modern symbols name chords directly (e.g., Cmaj7); Figured bass describes the chord in relation to the written bass, allowing for inversions without changing the figure.
• Misconception: A slash after a number means a rhythmic diminution.
  Correction: A slash can indicate that the figure applies to a shorter note value, but its exact meaning depends on the context and the composer’s conventions.