There is also a Medium version, which we regard as musically preferable, and in some cases an Inverted , where the rule is producing the opposite effect, for instance shortenings instead of lengthenings. Differentiation Rules enhance the differences between scale tones such as Do Sol, La, etc, and between note values such as quarter notes, eighth notes etc. Grouping Rules show which tones belong together and which do not. Tones constituting melodic gestures, such as belong together, as do tones constituting phrases. The rules mark, by means of micropauses and lengthening of tones, the boundaries between all these tone groups.
Ensemble Rules keep the order in ensembles.
They achieve sychronization by lengthening and shortening the individual tones in the various voices according to a common overall strategy and they achieve fine tuning of successive and simultaneous intervals. Most of them are implemented in the program Director Musices. Its manual has references to the relevant papers for each rule, also found in the publication list.