This opening movement is based in the organic fantasy sound world found in the early published sonatas but is much more propulsive and violent in its intensity. Unique to the movement (and the overall work) are the repetitive anchors on B throughout, the initials of the original dedicatee, Bernard Bromage. In addition, Bromage’s name is referred to in the opening chords, based around the motto G-A-B-E. Sorabji seems to have consciously discarded the method of cataloguing all the various themes he used in the Fourth Sonata, relying on a more instinctual approach to subconsciously reiterating various themes, mottos and phrases throughout the movement where he sees fit.

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