High Quality Content by WIKIPEDIA articles! James "Jim" Diamond (born 28 September 1953, Glasgow) is a Scottish singer-songwriter. Diamond is best known for his three Top 5 hits. The first was "I Won`t Let You Down" (1982), as the lead singer in the trio Ph.D., with Tony Hymas and Simon Phillips. His solo performance, "I Should Have Known Better", was a United Kingdom number one in 1984. The third track was the theme song from Boon, "Hi Ho Silver" which reached Number 5 in the UK Singles Chart in 1986. He has also featured as a vocalist on the charity No.1s "You`ll Never Walk Alone" with The Crowd and "Let It Be" with Ferry Aid.