Delme Jones was born on 29 March 1934 in Brynamman, a colliery village straddling the Carmarthenshire/Neath Port Talbot border in South Wales. He left school to work as a coal miner and was good enough on the rugby field to be capped for Wales at under-21 level, but singing was his real passion, and he eventually gave up both mining and the prospect of a rugby career to train as a professional singer, first under the Welsh baritone Redvers Llewellyn and then at the Guildhall School of Music and Drama in London, followed by further study at the Vienna Music Academy.
Performing under the stage name Delme Bryn-Jones — taking "Bryn" from his home village — he made his professional operatic debut in 1959 at Sadler's Wells Theatre. His breakthrough came at Glyndebourne Festival Opera, where, engaged as an understudy, he stepped in to sing the role of Nick Shadow in Stravinsky's The Rake's Progress and won wide notice. He went on to sing at Covent Garden and became a leading soloist for Welsh National Opera through the 1960s and 1970s, most notably in the title role of Macbeth and as Rigoletto, appearing opposite Gwyneth Jones during one of WNO's most significant periods of growth as a full-time company.
Critics generally praised the richness of his voice, especially in its lower register, though some felt his stage characterisations lacked polish. Away from the stage, Bryn-Jones battled alcoholism for years before overcoming it, and he spent much of his later life supporting others facing the same struggle. He died on 25 May 2001, aged 67, and is remembered as one of the finest baritone voices to come out of Wales in the twentieth century.