Warren Trevelyan-Jones Warren Trevelyan-Jones is the co-founder of the UK’s Ensemble Plus Ultra, which has recorded the Gradualia of William Byrd for Musica Omnia. Warren Trevelyan-Jones was last modified: August 26th, 2014 by moadmin Performed in: William Byrd – Gradualia (1607) Performed compositions by: William Byrd Warren Trevelyan-Jones was last modified: August 26th, 2014 by moadmin