Tetraedrum

The starting point for this polygon is a series of dyads in natural harmonics on the cello. This material is developed in symmetrical projections onto a four-note and later eight-note harmony. In the meantime, the opposition between the faces of the polygon comes to the fore, be it in sudden changes on right-hand technique on the whole group, or in the alternation of homophonic and polyphonic textures. The overall direction of the symmetrical projections reaches from the dyads to the open chords (heard at the beginning of the piece), and ultimately to the closure of the pitch space into the smallest possible cluster in semitones.