Global Musical Tempo Transformations using Case Based ... - OFAI

Differentiation Rules that help the listener to identify pitch and duration
categories.
Grouping Rules that help the listener to perceive contiguous sets of tones
as a group, or melodic Gestalt.
Ensemble Rules that specify the synchronization and tuning between different
voices.
The effects of the differentiation and grouping rules are additive and each
rule processes the score in a sequential order, from the start to the end. The
status of the ensemble rules is somewhat different: they only apply in the case
of polyphonic music, and they do not process the score sequentially, but as
a whole. When the ensemble rules are to be applied, the differentiation and
grouping rules that affect the timing and duration of the notes are applied to
a voice that is extracted from the score by certain guidelines, and the other
voices are synchronized to this voice, to avoid contradicting expressive effects
within different voices.
Examples of differentiation rules are:
Duration contrast Shorten the short notes and lengthen the long notes.
High sharp Increase the pitch of the notes; the higher the note the sharper
it is played.
Melodic charge Emphasize melodically charged notes (relatively dissonant
notes given a particular harmonic context). Emphasis is given by increasing
amplitude, duration and vibrato depth.
Examples of grouping rules are:
Leap articulation Insert micro pauses between two tones forming a leap
(a large interval) and create overlap between two tones forming a step
(a small interval).
Phrase marking Insert micro pauses between tones that separate two phrases;
in addition, increase the duration of the phrase-final tone.
Faster uphill Shorten the durations (i.e. increase tempo) of tones initiating
an ascending interval.
Examples of ensemble rules are:
Melodic synchronization extract an appropriate voice from the piece and
after applying the timing and duration varying rules to that voice,
synchronize the other voices to the notes of that voice.
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