[4] He then studied the trumpet under George Eskdale for a year at the Royal Academy of Music, where he was awarded the Certificate of Merit for Conducting in 1957.
[6] After this training, in 1960, he was appointed Bandmaster with the Royal Marines, where he served for three years as Director of Music to the Commander-in-Chief, Mediterranean, and also conducting the Malta Choral Society.
[3] He conducted a section of the Royal Marines Band at Sadler's Wells Theatre during a first-act performance of H.M.S.
[2][4] He was in charge of the centenary season at the Savoy Theatre in 1975, where all the Gilbert and Sullivan operas from Trial by Jury to The Grand Duke were presented in chronological order.
[2] In 1977, during Queen Elizabeth II's Jubilee Year, the company gave a Royal Command Performance at Windsor Castle, conducted by Nash.
[9] Nash moved to North America in 1979, and in 1980 he became musical director of both the Nashua Symphony Orchestra in Nashua, New Hampshire, ending with the 2006–07 season, and of the Cape Cod Symphony Orchestra in Massachusetts for 27 years until 2007, where he was then Music Director Laureate for life.
He had two sons, Adrian Wesley (1953–1993) and Kelvin Howard Nash (born 1960),[3] from his first marriage to Joyce Gladys (née Murdoch) in 1952.