Listen to Y Deryn Pur online. Y Deryn Pur is a Welsh language song and is sung by Treorchy Male Voice Choir and John Haydn Davies. Y Deryn Pur, from the album Welsh Male Voice Choir Tradition: Treorchy Male Voice Choir, was released in the year 2017. The duration of the song is 2:34. Download Welsh songs online from JioSaavn.