Cap 8 - Canon PT2 Flashcards
Melodía del canon
Whether a melody can be treated canonically ( and if so, what interval will be successful) is determined by the nature ofthe melody itself.
Many melodies do not lend themselves at all to canonic treatment, while others may make effective canons at severa! different intervals. In any case, a certain amount of tria! and rejection is usually
required before successful results are achieved.
ESCRITURA DE CANON A DOS VOCES:
Sugerencias generales
1- begin by writing the leader only up to the point where the follower is to enter.
2-This same material is then written in the follower at whatever harmonic interval is being used,
3-The leader is continued in a manner consistent with good counterpoint.
4-This material in the leader will in turn be transferred to the follower, and so on.
Problemas y soluciones en canons a octavas o a unísono
The chief problem in writing canons at the octave or unison is that of avoiding harmonic monotony.
The problem arises beca use the notes of segment I in the leader are repeated as segment 2 in the follower.
Segment 3, which is a counterpoint for segment
2, is then repeated as segment 4 in the follower, and so on.
The solution is obviously to change the harmonic
implications of certain notes where that seems indicated for the sake of variety.
In C major for example, the note G could be the fifth of the tonic chore!, the root of the dominant, the third of the mediant, or the seventh of a submediant seventh chord. lt could even be made to sound nonharmonic
Los silencios (4 beneficios)
Do not be afraid to use rests from time to time.
1-Sirven para articular los segmentos de la línea
2-Dan un respiro a la melodía
3-Incrementan el sentimiento de independencia entre líneas
4-Agregan interés cambiando la atención de una voz a otra.
CANONS USING SPECIAL DEVICES
The devices of contrary motion (inversion), augmentation, diminution, and retrograde
motion may be applied in canonic writing.
CANONS USING SPECIAL DEVICES:
Contrary Motion
In contrary motion the upward or downward direction of the leader is reversed in the follower, but the basic melodic intervals rernain the same.
CANONS USING SPECIAL DEVICES:
Augmentation
In augmentation, the original note values are increased (most often doubled) in the follower.
For instance, in Example 1 1 the two outer voices form a canon at the octave with the bottom voice moving in values twice as long as those in the leader. The middie voice is free, but imitates the upper one at the start.
PROBLEMA:
Notice that when augmentation is involved the follower can never overtake the leader and that, in fact, it gets farther and farther behind, in terms of imitation, as the canon progresses.
SOLUCIÓN:
Bach sometimes solves this problem by stating the leader twice against one augmented statement in the follower.
NOTA:
In composing a canon in augmentation, avoid very long values or continued suggestions of the same harmony in the leader. If this is not done, the augmented imitation will tend to bog down rhythmically or harmonically.
CANONS USING SPECIAL DEVICES:
Diminution
In a canon in diminution, the follower is moving in values shorter than those of the leader and may overtake it.
If the canon is at the octave and is continuous, parallel octaves between the voices are inevitable at that point.
Another way of avoiding the overtaking process in a canon in diminution is to start both voices at the same time, at what would have been the overtaking poin. Although such an arrangement is contrary to our definition of canon in that the voices enter together rather than consecutively, the
exception seems warranted here, whereas it did not in the case ofthe “mirror.”
In writing a canon in diminution, a point to remember is this: ifthe leader contains very short values, the diminution in the follower is likely to sound unnaturally hurried, somewhat like a recording being played at too fast a speed.
CANONS USING SPECIAL DEVICES:
Retrograde Motion (crab canon)
In a retrograde canon, also called crab canon or canon cancrizans, the melody played backwards accompanies the melody in its original form.
The procedure for writing a canon in retrograde motion is to compase the first half of the leader, then write that part backwards as the last half of the follower. Next, by a process oftrial and error, find a line that will work forward as the last halfofthe leader, and backward as the first half ofthe follower.
FUGAS Y STRETTOS
The word stretto means “tight” in ltalian.
A stretto is a passage in which the musical idea in one voice is overlapped by the same idea- or, rarely, by a different one-in another voice.
In fugues, the subject is often treated in canonic fashion for short periods to form a stretto.
