Grade 5: Rules of Four-Part Writing (i)
There are a few rules for 4-part writing.
i) The third of a triad (the note which forms the third with the bottom note) must be included, but not doubled.
A C major triad consists of the notes C-E-G.
In the examples of C major chords above, the third chord is incorrect, because there are two Es.
However, if a chord is a minor chord, it is sometimes permissible to double the third.
In the example of the C minor scale above, the third chord is permissible, even though the third is doubled.
ii) There should not be a gap of more than one octave between parts. However, a gap of more than one octave between the tenor and bass is allowed.
iii) Parts should not overlap.
The parts marked “X” are incorrect because the alto part (lower note in treble clef) is lower than the tenor part (higher part in bass clef). This is called overlapping.
Using SATB, write chords Ic and V for the following keys:
C major
G major
A minor
