Born in Machynlleth, Wales, Glyn is the eldest son of the late Welsh poet T. Glynne Davies.

He received his secondary education at Ysgol Maes Garmon in Mold,[1] before attending Merton College, University of Oxford, 1969–72, studying music and specialising in composition.

He has produced one symphony, and many of his recorded orchestral works are in the light music genre, including A Snowdon Overture, Legend of the Lake and Anglesey Seascapes.

In 2011, to coincide with his 60th birthday, a double CD of a selection of his orchestral works was released by Sain, including the substantial Enduring City celebrating the 300th anniversary of the founding of the city of New Bern.

[2] Glyn used to present the news and current affairs programme Post Prynhawn, broadcast on BBC Radio Cymru from Mondays to Fridays in the 5–6pm slot.