Comeau was born in 1993 and grew up in Truro, Cornwall. As a child, he sang with the choir at Truro Cathedral, becoming interested in Bach and jazz music. He obtained an LRSM diploma with distinction in piano, and a Royal College of Organists diploma. In 2011, he won the first Northern Ireland International Organ Competition, playing his own arrangement of Igor Stravinsky's Firebird Suite. He studied at Girton College, Cambridge, where he was the college organ scholar, and graduated with a Bachelor of Arts in music in 2014. He gained a postgraduate degree in music from the Guildhall School of Music and Drama.
