Markus Reuter's Todmorden 513 is a complex work of algorithmic composition of an hour's duration. Given Reuter's linguistic background, one might think that the title is an exercise in existential dread in German as "Tod" means "death" and "morden" means "to murder" - forming a truly grim portmanteau. However, the title's sourcing is actually of a small town in northern England, northeast of Manchester. 513 refers to its construction: it is a continuous movement and sequence of five hundred and thirteen harmonies and triads generated by a combinatorial compositional technique of Reuter's own design. The notes of each harmony or triad is then fed back into the same algorithm, resulting in a progression of chords and note clusters of highly varied density, ranging from simple two note harmonies to dense twelve note chords spread across several octaves. Starting on an A flat, the sequences of pitches form a kind of melodic or thematic line throughout. The rhythms of the performing instrumental trios and quartets were derived from the chord sequences themselves, which were looped across the whole piece, mapped to the notes of each chord, then mixed together. From there it was split into three or four independent voices respectively. The result is a shifting set of harmonic densities -- at times quite spare -- ranging from a harmony of two instruments to other moments of thick and lush instrumentation.
Movements 4 and 5 from the world-premiere performance at the King Center Concert Hall in Denver, CO on April 18 2013.