He participated in the Blackpool musical scene, with most of the musicians that would become Jethro Tull, including Barrie Barlow, Jeffrey Hammond, Glenn Cornick and Ian Anderson.

In addition to his many distinctive contributions to the group's overall musical sound and stage personality, it is also notable that Evan composed the memorable piano introduction to "Locomotive Breath", having achieved this task in studio while some of the other band members were out to lunch.

Whilst with Jethro Tull, Evan had a penchant for wearing his trademark white suit, along with a yellow shirt underneath and a pink-and-yellow polka-dot tie.

During concerts, Evan's wildly rendered pantomime gestures would conjure visions for audiences of a cross between Harpo Marx and The Hatter from Alice's Adventures in Wonderland (sans the hat).

Because of the familiar white suit, Anderson was known to jokingly refer to Evan (during band member introductions) as "everyone's favourite ice cream salesman".