When in Free Counterpoint the Set Style window offers you the below options for rhythm rules. You can choose any combination of the possible rules and exceptions. These principles apply to each melodic line, independent of the other voices. In the ideal polyphony each melody is of equal value and "makes sense" on its own. In practical music it is also true that some voices will in fact be more important than others.
Note values have changed over time; today's "whole note" was formerly played much faster than a whole note is today. To keep things flexible we'll call "rapid" any notes whose value is one half-beat or less. Speed of notes will always be described in its relationship to the beat. For example, in 2/2 time the half note has the beat, so a quarter note is "rapid." But in 4/4 time the quarter note has the beat so the eighth note is "rapid."
Passages should not begin with rapid notes.
Allowed if the passage begins offbeat. Examples:
Voices should not begin together. In all counterpoint exercises except for first species, it is customary to emphasize the independence of voices by letting each enter individually. An exception would be a second, third, or fourth species exercise in more than two parts. In that case all but one voice will be in first species (beginning together) and the remaining voice with the faster movement will enter after a rest.
Rapid notes should move by step only. This is partly for singability and partly for ease of comprehension
Allow leap of a 4th or less if compensated by step.
Rapid notes should begin in an unaccented position. That is, not on a downbeat, and not as the first of a pair of notes of equal value.
Anapest (short, short, long) is undesirable on a beat. This is related to the previous rule but more specific.
Avoid using rapid notes.
Allowed up to value of one beat per measure in each voice. This amounts to a method of keeping the voices relatively calm.
Allowed up to value of one half measure in each voice.
The first note of a tied pair must be the same length or double the length of the second.
The first note of a tied pair must be longer than the second. A more permissive version of the above rule.
The first note of a tie must be no less than a beat in value.
The first note of a tie must be no more than a half measure in value.
The next rules are specifically for use in species counterpoint exercises. Species counterpoint organizes study by breaking the art into arbitrary modes known as first species (each part moves together with the others; no independent rhythm), second species (one part has two notes for each note of the others), third species (one part has 4 notes for each note of the others), fourth species (one part has two notes for each of the others, but always syncopated with the second note of each pair tied ahead.) In triple meters the species are modified as follows: first species is unchanged, in second species one part has three notes for each of the others, in third species one part has six notes for each of the others, and in fourth species one part has two syncopated notes for each note of the others but the first is long and the second short. Fifth species is the simultaneous combination of the first four. When doing Second through Fifth Species exercises with more than two voices, the normal practice is to leave all but one voice in First Species.
Observe first species rhythm.
Observe second species rhythm.
Observe third species rhythm.
Observe fourth species rhythm.
Observe fifth species rhythm.
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