Jones was born in Pembroke, Wales. He studied at the University of Wales and the Royal Academy of Music and was awarded the Mendelssohn Travelling Scholarship, which allowed him to study abroad.
He was a friend of Dylan Thomas from childhood, and wrote music for a radio production of his Under Milk Wood. Jones' fourth symphony is dedicated to Thomas' memory, and he also wrote a biography of the poet, My Friend Dylan Thomas (London, Dent, 1977).
Jones wrote twelve numbered symphonies in all, plus a later Symphony in Memory of John Fussell. Among his other works are chamber music, including several string quartets and a sonata for three timpani, orchestral and choral works, and several operas.