Frank Zappa's Mothers of Invention co-founder Ray Collins has died after suffering a heart attack.
The 75-year-old singer died in a California hospital on Monday after doctors took him off life support.
Collins famously hired Zappa as the guitarist in his band the Soul Giants in the mid-1970s and formed the Mothers of Invention with the eccentric rocker in 1966.
He sang on classic tracks like Who Are the Brain Police? and Hungry Freaks and recorded two albums with the Mothers before quitting the group over creative differences.
Collins later retired from the music business and took on a series of odd jobs as a taxi driver and a dish washer.
For many years his only income came from songwriting royalties and Social Security, according to Rolling Stone.