Fischer, who was ravaged by manic depression and schizophrenia all of his life, had a brief and sometimes stormy relationship with Frank Zappa and was known around the LA hippie scene as a panhandler with a gift for improvising listenable tunes.
He succumbed to heart failure at Ronald Reagan UCLA Medical Center Thursday.
The Los Angeles Times said Saturday that Fischer released several albums and was the subject of Zappa's 1968 release "An Evening With Larry Fisher."
Zappa told an interviewer in 1970 he had no illusions about dealing with someone like Fischer, whose fits of genius were tainted by mental illness. "One thing that you must remember about Wild Man Fischer is that he actually is a wild person," Zappa warned. "And Larry is dangerous.
Fischer lost much of his edge in 2004 when his family convinced him to move into an assisted-living facility in Van Nuys and get back on the medications he had abandoned 40 years earlier.
"Sadly, the cost associated with taking the medications to control that illness was that he completely lost what he called 'the pep,'" documentary producer Jeremy Lubin told the Times Friday. "The pep stemmed from that manic energy that would compel him to just burst out into song and write and create music."