Reflections on A7

For Peter Webster

Reflections on A7 is my first piece exploring symmetry and retrograde processes. Written for Peter Webster's birthday, the piece is based around a central chord of A7. This can be found in the middle bar of the piece (b29), everything either side of this chord is a reflection of its symmetrical bar. For example, bar 1 is bar 57 backwards, bar 2 is bar 56 backwards, bar 3 is bar 55 backwards - etc. The piece was written between the 27th-28th June, 2007.

The piece naturally falls into ternary form (again highlighting the symmetrical structure) with bars 1-17 forming the first section, bb18-40 the middle section, and bb41-57 the final section. Symmetry can be found at a deeper level too. As a result of the symmetry, the middle section (18-40) is perfectly symmetrical (around the A7 in b29). I wanted to maintain this inner symmetry in the outer section as well. Therefore the outer sections also contain symmetry/reflections. That is bar 2 is bar 16 backwards, bar 3 is bar 15 backwards etc. This is naturally mirrored in the final section. In addition, when the main motif appears (as in bar 2) the left hand is the retrograde of the right hand.

The chart below makes sense of the structure. Click to enlarge.