Check Harmony Rules

Check Harmony Rules - check Soprano, Alto, Tenor, Bass for conformance to good harmony writing rules.

Installation instructions:

1. Download locations:
   • Download for MuseScore 4.4 or later (updated by Marc Sabatella)
   • Download for MuseScore versions 4.0 - 4.3 or 3.x (created by Louis Cloete and updated by Marc Sabatella)
   • Download for MuseScore version 2.x (created by heuchi)
   • Download for MuseScore version 1.x
2. Save in the Plugins directory of MuseScore (unzip if necessary when using an older version)
3. Restart or start MuseScore
4. Activate the plugin using the Plugin Manager

Current feature list:

Please note that current versions of the plugin might behave slightly differently since it's not a direct port but has been rewritten.

Checks are based on pp. 5, 6 & 7 of the textbook, "First Year Harmony," by William Lovelock. Note: This plugin does NOT check whether the leading note rises to tonic in the progression V-I (p.6, 11.f). The other checks on these pages, 11.a to 11.e, 11.g, 12.a & 12.b are checked.

Multi-voice Checks:

1. Checks for parallel perfect 5ths and octaves, including consecutive 5ths and octaves in contrary motion, and unison to octave and octave to unison. (Note: different intervals that are enharmonically equivalent to a perfect 5th or octave are NOT detected).
2. Checks for exposed 5ths and octaves. Note: an exposed 5th between II and V is allowed by Lovelock's textbook, but this plugin will still mark it as a problem. It is up to the composer to recognize such exposed 5ths as being acceptable.

Single-voice Checks:

The following errors are detected for each voice selected (or all voices if nothing was selected):

1. All augmented intervals between one note and the next
2. Diminished 5ths, when they are not followed by a note within the interval
3. Leaps of a diminished 4th and 7th (if you, unlike me, are not a novice composer, you may know how to use these intervals correctly; use your discretion).
4. Leaps of a 6th are better avoided, but should be followed by a note within the interval
5. Octaves, when they are not preceeded and followed by a note within the interval
6. Leaps of a 7th, 9th or larger, even with one note intervening

Text is written to the score above any such intervals detected to notify the user of their existence, and the notes themselves are changed to red colour. Using the undo button will easily undo all changes.

Currently, there are no plans to add any further checks.

Assumptions made about the score:

1. Each voice should only have one note at a time (i.e. one note per museScore "chord"). If a voice contains a chord of two or more notes, it is annotated as an error on the score.
   To check your chords properly, each voice should play only one note at a time, as only the top note of each museScore chord in a single voice is checked.
2. If there is a selection, only the selected notes are checked. If nothing is selected, the entire score is checked.
3. Any number of voices may be checked at once, but if there are more than four voices, consecutive octaves may be more likely.
4. For the purposes of MULTI-VOICE analysis, if different voices contain simultaneous notes of different lengths, the longer note(s) are treated as if they were split into shorter notes of the same length as the shortest simultaneous note. No notes on the score itself are changed (apart from the colour of the notes).
5. For the purposes of analysis for the SINGLE-VOICE checks, no notes are split. Consecutive notes of the same pitch ARE TREATED AS ONE NOTE for the analysis (the score itself is not changed). I am only a novice composer. If you think consecutive notes of the same pitch should not be treated as one, please raise this as an issue.