454. A CHORD AS A GROUP OF MODULATION-VARIATIONS OF MELODIC THEMES OVER THE CHORD.

  A CHORD AS A GROUP OF MODULATION-VARIATIONS OF MELODIC THEMES OVER THE CHORD. 

The elements of  the group are modulations-variations, and the generators of the group are defined by the intervals of the chord. The exact definition of the variation of a chord-fitting melodic theme is such that it holds group closure to the operation of composition of variations. E.g. idempotent  a^2=1, where repeating a shift by an interval is with its complementary interval .

The most relevant layers of the melody is the 1st layer of simplicial submelody, and  the 2nd layer of the arpeggios over the chord. 

The part of a poetic measure corresponding to a chord, is of course a guide too.

453. WRITTING A MELODY OVER A CHORD PROGRESSION AS IF WRITING A POEM WITH SYLLABIC METER.

 

This idea is mainly the one described in 8-bars blocks songs in previeous  posts .

The first 4 bars, have 2 chords one per 2 bars, and the  chords and melodic themes as well

have the pattern of the 8 bars 

Chords          A  A   B  B

                      A  A   C  C

Now each line of 4  bars (AABB, or AACC) may be conceive as a poetic line

e.g. of 15-sylables poetry .