DIFFERENTIALS

for Clarinet and Piano 1968

David Hellewell

DIFFERENTIALS was a further extension of compositional procedures first used by the composer in his Piano Piece 1967.

The work is in three broad sections which are played without a break. The main features of the first section are a moderate loping rhythm and wide melodic leaps for both instruments. At the end of this section the music builds up to a climax which culminates in high trills, and then merges into the second section after a fortissimo chord cluster which is transformed into harmonics by the use of the sustaining pedal.

The second section exploits extreme contrasts of violence and tranquillity. The basic tempo is very slow and calm, but there are many sudden changes of meter throughout the movement. In this section the clarinet and piano are intricately interdependent, which demands an exceptional degree of rapport between the players; there is also some use made of piano harmonics and clusters.

The main feature of the final section is its fast tempo and complex rhythms, coupled with a more contrapuntal treatment of the parts. From the initial tempo (vivace) the music is eventually precipitated into a fast climactic section (prestissimo) which is brought to a halt with both instruments playing fortissimo in their lowest registers.

There are further outbreaks of this fast violent music, but now interspersed with pauses and calmer passages, until the music finally achieves complete abandonment and drives through to a final subsection (molto pesante) in which the clarinet screams out its highest note against fortissimo chords from the piano.

1st performance by Anthony Lamb (cl), for whom it was written, with the composer at the piano, in 1969, Bournemouth.