There are a number of guidelines that you should bear in mind when you are writing four-part cadences in the style of a Bach chorale. Some of these guidelines can be considered as rules, but most concern part-writing that is characteristic and the various considerations have to be weighed against each other.

The last two chords of a cadence are almost always in root position. You should only use inversions if you are following a standard cadential formula (e.g. ascending quavers in the bass at an imperfect cadence)

Texture

• all three notes of the triad should be present in each chord
• it is best to double the root
• it is fine to double the third in first inversion chords
• it is good to double the fifth in a cadential six-four
• never double the seventh
• the largest gap should between the tenor and the bass

Motion between the voices

• never move to a fifth or octave in parallel motion
• avoid motion to a fifth or octave in similar motion
• it is best to have some contrary motion between the voices although cadences are the places where this guideline is least often followed
• parts should rarely (if ever) cross over

Individual parts

• parts should usually move by as small an interval as possible (except for the bass)
• it is therefore best to keep notes in common between the two chords in the same voice
• a fifth is the absolute maximum leap
• the voices should mostly stay within the following ranges:
  soprano - c1 to g2; alto - g to d2; tenor - c to f1; bass - E to c1 [this system of note-labelling is explained in basics]

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