The musician's relatives have declared they are "deeply shocked" by his sudden death on Saturday (10Oct15).

A family spokesman says, "He was a devoted family man who loved his wife Chrissy and his children Sara and Lawrence, and the music that he continued to make.

"He dedicated a lot of time over recent years to the Cash for Kids charity appeal in Scotland with his friend Sir Tom Hunter and was still active and well respected on the music scene. He'll be much missed by all who knew him and everyone who loved his music and his unique voice and style."

Jim, who was born in Glasgow, Scotland, was influenced by the voices of U.S. soul and blues singers, and was branded "Scotland's answer to Ray Charles" by editors of the Scotsman newspaper in 1993.

He had hits including I Won't Let You Down with his former band Ph.D, and solo release I Should Have Known Better, which was nominated for an Ivor Novello award. Jim also wrote the theme tune for the U.K. series Boon, which starred Michael Elphick.

His last album, which was released in 2011, was a compilation of soul covers featuring an array of Scottish musicians.