Duncan is a composer and sound artist whose practice utilises acoustic and digital forces. His output encompasses audio augmented reality, concert music, creative technologies, digital storytelling, performance, social practice, sound installations, soundwalks, and interdisciplinary practice that engages a variety of sources that include acoustic ecology, ethnography, folklore, science, and social and political issues. His work is commissioned, exhibited, performed and broadcast internationally by, amongst others, the Arditti Quartet, duoDorT, Fretwork, Galvanize Ensemble, Goldberg Ensemble, Jane Chapman, Juice, London Sinfonietta, Ensemble Okeanos, Making Music, Piano Circus, Tate Modern, and Whitechapel Gallery. Awards include two Sound & Music Shortlisted Composer awards, Handel House Composer in Residence, and in 2023 nominated for an Ivor Novello Award.

Duncan is also an active performer (voice/electronics) and founding member of SounDKard with Sarah Dacey (voice) and Kate Halsall (keyboards).

Duncan is Associate Professor in Music Composition and Sound Art at the University of Nottingham, UK.