82.113Mini-composition exercise

Write a 32-bar piece that begins tonally, enters symmetrical harmonic space, and returns to tonality.

Requirements:

• opening clearly establishes one major or minor key
• one C-like tonic→augmented→destination transformation
• one chromatic-mediant move with a preserved common tone
• one diminished seventh used as a genuine modulatory junction
• one dominant ♭9 whose diminished upper structure is clearly audible
• one whole-tone dominant passage
• one augmented/major-third root cycle
• one tritone-substitution event preserving the guide-tone shell
• at least four bars where tonic gravity is deliberately weakened by symmetrical material
• one motif sequenced through a symmetrical interval pattern
• symmetry must be broken by a deliberately asymmetrical tonal event
• final cadence must be simpler than the symmetrical climax

The listener should experience:

home → geometry → uncertainty → new possibilities → gravity restored.