Obituary (Courtesy of The Guardian Arts Pages).

Gifted harpist at home in the Irish music world of the Chieftains, and on the classical stage

Derek Bell, who has died aged 66 following minor surgery, was the harpist - and the only Ulsterman - with the Irish music group, the Chieftains. He was equally renowned as a classical performer.

Born in Belfast, he was surrounded by music from the age of two, when a misdiagnosis of imminent blindness led his parents to compensate by giving him a musical environment. He took up the piano, and wrote his first sonata at the age of 12. He graduated from the Royal College of Music, London, in 1957, took a music degree from Trinity College, Dublin, two years later, and subsequently studied in Europe and the United States. His teachers included Leon Goossens and Rosina Levine.

By this time, Bell had extended his range to include the oboe and the horn, as well as the harp. He appeared with the Royal Philharmonic and the American Wind Symphony orchestras, before taking up the positions of harpist with the BBC Northern Ireland orchestra and harp professor at the Belfast Academy of Music.

His path first crossed with the Chieftains in Belfast in 1972, when the group recorded a television performance, with the BBC orchestra, of Carolan's Concerto, by the blind, 18th-century Irish harpist Turlough O' Carolan. Captivated by Bell's playing, the Chieftains' leader, Paddy Moloney, booked him for guest appearances - Moloney said later that "the introduction of the harp completed the sound that I had always wanted to achieve".

Bell first recorded with the Chieftains in 1973, making an immediate impact on the album Chieftains IV with another Carolan composition, Morgan Magan. He officially joined the group in 1974, temporarily retaining, with some difficulty, his BBC post. On one occasion, his request for yet another spell of unpaid leave was greeted by an exasperated administrator: "Derek! When are you going to give up that tatty folk group?"

By the late 1970s, however, the tatty folk group had become an international attraction, helped by Stanley Kubrick's use of their music on the soundtrack of his film Barry Lyndon (1975), and there were tours of Europe, north America and the Far East.

Bell's harp added extra colour to the mix of flute, uillean pipes, fiddle, bodhran and tin whistles; his formal dress - crumpled suit, pullover and tie - contrasted with the casual style of his colleagues, and his bemused expression and quiet demeanour offset the animation of Moloney, the showman. Announcing the solo pieces that became a highlight of the stage shows, Moloney mischievously nicknamed the harpist "Ding Dong Bell".

Particularly on foreign tours, Bell had a reputation for eccentric behaviour. After receiving the freedom of an American city, he had to be warned by the local police chief not to wander in certain districts as he might get mugged. Later, he was stopped at Moscow airport on suspicion of carrying a lethal object, after he had stuffed an alarm clock into his pocket in the rush to catch the plane in Belfast.

As some of the Chieftains grew tired of the global touring schedule, there were personnel changes in the group, but Bell and Moloney were ever-present. Bell also seemed to relish Moloney's zest for eclectic musical combinations, from collaborations with rock artists such as Van Morrison and Sting to a joint concert with a Chinese orchestra during the Chieftains' 1985 tour. Altogether, Bell contributed to more than 30 Chieftains albums, including Over The Sea To Skye (1991), which featured the Belfast-born flautist James Galway.

Simultaneously, he maintained his career as a classical composer and harpist, writing three piano sonatas and two symphonies. The second symphony, The Violent Flame, Comte de Saint Germain, was performed at the 1991 Edinburgh festival with the Northern Ireland Symphony Orchestra. Three Images Of Ireland In Druid Times (1993), for Irish harp, strings and timpani, was premiered in Boston, and he also recorded eight solo albums, including two of Carolan's compositions and several of traditional Irish music. He was awarded the MBE in 2000.

Bell died in Phoenix, Arizona, having been recording and appearing in Nashville as part of the Chieftains' 40th anniversary celebrations. He is survived by his wife Stephanie, his mother and two sisters.

� Derek Bell, harpist, born October 21 1935; died October 17 2002