In July 1998, while working on Havoc, which had been commissioned by the BBC for the 1999 Proms, I decided to use a theorbo in the score. Since my technical knowledge of the theorbo (which is also known as the chitarrone) was almost non-existent, I contacted the leading theorbo-player Dai Miller, who was booked to play in the Proms performance. He kindly showed me how the instrument worked, and I began writing Groundwork as a technical exercise for myself. Hence one meaning of the title; the other being that the piece is a set of variations over a ground bass.

Since the theorbo has eight diapason bass strings - which are in fixed tuning and played like those of a harp, and not stopped with the left hand - it seemed sensible to use these for the ground bass, which consists simply of a rising eight-note scale using all diapason strings, one after the other. This ground is stated at the beginning, and developed through sixteen variations. The first seven are fairly straightforward, except that variations three and four compress the ground, putting the second half (notes 1-4) backwards against the unmodified first half (notes 5-8). The remaining variations are in stretto - gradually overlapping each other, with the ground beginning one note earlier on each reappearance. The climax of the piece comes at variations ten and eleven; variations twelve to fourteen bring things gradually down to earth; variation fifteen is quiet, putting the decorated ground in canon with itself (in octaves, using the top and bottom strings of the instrument). The last variation strips the ground of all decoration, putting scrunchy chords above it. The piece ends with the lowest diapason string (G), a quiet ripple on the other seven diapason strings, and a final high harmonic (G again) to tell us that our journey is over. The piece lasts about six minutes.

Giles Swayne
2025