FIGURED BASS
FIGURED BASS
Introduction to figured bass
This video introduces the central concepts behind figured bass. As mentioned in the previous lesson, Figured Bass is an archaic shorthand method for writing chords that was popular in the 17th and 18th centuries.
COMMON CHORDS IN FIGURED BASS
5-3 Chords
5-3 means root position chord.
Look at the bass note (B). Add a note which is a fifth higher (F#) and another which is a third higher (D). This makes a root position chord: B-D-F#.
The F# and D can occur in any octave, and because this is four-part harmony, one of the notes will need to be repeated.
In this example chord, the B (root) is repeated in the tenor part, and the F# and D are on the treble stave, built as compound intervals (more than an octave) from the bass note.
The bass = the root of the triad
The tenor = the root of the triad (doubled bass note)
The alto = the fifth of the triad AND the five of the figure
The soprano = the third of the triad AND the three of the figure
Here is another example of the same figure interpreted in a different way. This time the root B is doubled in the soprano part, and the F# and D occur in the middle parts, the alto and tenor.
Because root position chords are so common, the "5-3" figuring is usually left out. If you see a bass note without any numbers at all, it means it's a 5-3 or root position chord. (It does not mean that you can write any chord you want!)
6-3 Chords
A 6-3 chord is a first inversion chord.
The notes we need to write are a third and a sixth above the bass note.
Here is a bass note C. We need to add a note a sixth higher (A) and another a third higher than the bass (E).
This gives us the chord notes C-A-E, with C in the bass. It is an A minor chord in first inversion, with a doubled root.
Bass = third of triad (A-C-E)
Tenor = root of triad (A-C-E), or six of the figure (a 6th above the bass)
Alto = fifth of triad (A-C-E), three of the figure (a third above the bass)
Soprano = root of triad or six of the figure
Here is a different interpretation of the same figured bass. This time the third of the triad has been doubled (A-C-E)
Because 6-3 chords are also very common, they are usually just written as a lone 6 instead of 6-3. The figure 6 means first inversion.
6-4 Chords
A 6-4 chord is a second inversion chord.
The notes we need to write are a fourth and a sixth higher than the bass note.
Here the bass note is C. The figured bass tells us to add F (a fourth above C) and A (a sixth above C). The chord notes are C-F-A, which is F major in second inversion.
Bass = fifth of triad (F-A-C)
Tenor = third of triad (F-A-C) or six of the figure (a 6th above the bass)
Alto = root of triad (F-A-C) or four of the figure (a 4th above the bass)
Soprano = fifth of triad (doubled bass note)
Here is another interpretation of the same figured bass note.
6-4 chords are always figured in full - they are not missed out or abbreviated like the 5-3 and 6-3 figures.
Chromatic Alteration
Figured bass sometimes includes sharps, flats or naturals. The accidental is written next to the figure which it affects.
If the accidental is not next to a figure, but just appears on its own, then it always refers to the 3rd above the bass.
For example:
= sharpen the 3rd.
The chord notes will be F# (key sig), A# (accidental) and C# (key sig). This is an F# Triad in root position.
= sharpen the 6th. The chord notes will be C#, F# and A#.
Again, the notes are The chord notes will be F# (key sig), A# (accidental) and C# (key sig). This is an F# triad second inversion.
Chromatic alteration is very common in minor keys, where the dominant chord has a sharpened third which does not appear in the key signature. For example in A minor, the dominant chord is E major, with a G sharp accidental.
Often a sharpened note in figured bass will be expressed as a line or slash through the number, rather than using an accidental.
Lines
Horizontal lines in figured bass mean that the same harmony applies to two or more notes. It means "don't change the chord!".
