Gascoyne studied piano from the age of six and became highly accomplished on the instrument. While in school he switched to playing bass in punk and other contemporary pop bands. In the early 90s he played bass with Everything But The Girl, a jazz-tinged pop band, but also depped in various jazz bands including Jim Mullen ’s, alongside Mornington Lockett and Dave O’Higgins. Gascoyne then went with Georgie Fame, remaining for more than a decade. Meanwhile, he became a highly respected studio musician, playing bass with many leading artists in pop and jazz, among them Peter Churchill and Guy Barker, appearing on-screen in Barker’s band in The Talented Mr Ripley (1999). In 1995 Gascoyne had met and played bass with singer Trudy Kerr ; they were married in January 2002.

In the new millennium, Gascoyne continued to appear on numerous albums with a wide variety of musicians, notably Jamie Cullum, playing with him in duo, various ad hoc bands, and in the singer-pianist’s own band, a relationship that led to worldwide tours. Gascoyne also formed his own Project band, which combines jazz and chamber music groups, and includes Martin Shaw, Tim Garland, Sebastian De Krom, Cullum and Kerr.