Harmony Rules!

Here are some rules to help you write chords and cadences:

HARMONY RULES WRITING CHORDS
• Double the root or 5th, NOT the 3rd except in a minor chord (not key). Chord VI is the big exception, DO double the 3rd.
• Try to make the spacing of each chord as even as possible.
• No more than one octave between Alto & Tenor and Alto & Soprano.
• Do not leave out the 3rd
• The 5th may be left out and the root tripled
• Never double the leading note of the scale.
• It is occasionally possible to have Alto and Tenor on the same note.
• Keep the tenor part as high as possible.

WRITING CADENCES
• The leading note of a scale must rise to the tonic.
• When both chords use the same note keep it in the same part.
• Parts move to the nearest note possible.
• No part may move in parallel or consecutive 5ths or octaves.
• No part may overlap or cross another part.
• Contrary motion is desirable where possible.

PERFECT CADENCES
• The perfect cadence is chords V – I and has a very finished sound ideal for the end of piece or section of the music. Write down the available notes, in C Major the notes are GGBD and CCEG. Occasionally it may be necessary to double the 5th of chord I (CEGG) or even triple the tonic (CCCE), to keep to the basic rules.
• Always begin by writing in the bass notes.
• The leading note rises to the tonic.
• The note common to both chords remains in the same part.
• This leaves only one pair of notes which move by step.

PLAGAL CADENCES
• A plagal cadence is chords IV – I and has a finished sound bring the music to a close.
• We work these exactly as for the perfect cadence except there is no leading note.
• Write in the bass notes (the root of each chord).
• Keep the note in common to both chords in the same part (this is the tonic of the key).
• The other two parts should move as closely as possible, usually they can simply both move down a step.