Ed Cassidy, the drummer for the classic rock band Spirit, died in San Jose, Calif. on Thursday (Dec. 6) of undisclosed causes. Notable for his shaved head (which inspired the nickname "Mr. Skin"), head-to-toe black wardrobe and massive drum kit, Cassidy was considered very influential on other drummers of the '60s rock era. He was 89 years old at the time of his death.

Born on May 4, 1923 in a rural town outside of Chicago, Cassidy began his career at an early age in 1937, after his family moved to Bakersfield, Calif. He served in the Navy during World War II and thereafter held a series of jobs before returning to music full-time in the '40s, working steadily in a succession of show bands, country and western acts, and big bands. He also worked on film soundtracks and played briefly with the San Francisco Opera.

Cassidy spent the '50s working primarily in jazz in California, playing with such historically important performers as Art Pepper, Roland Kirk and Gerry Mulligan. He played with Taj Mahal and Ry Cooder briefly in a band called Rising Sons before forming a new group, the Red Roosters, in 1965. That group comprised Cassidy, his stepson Randy California on guitar, Mark Andes on bass, and singer Jay Ferguson.

Changing their name to Spirit with the addition of keyboardist John Locke, that ensemble created a sound that was an amalgam of jazz, hard rock, and psychedelic influences. Signed by '60s L.A. music impresario Lou Adler, the group released their self-titled debut album in 1968. They followed it up with 'The Family That Plays Together' later that year, which featured their highest-charting single, 'I Got a Line on You.'

In 1969 they toured successfully with a then-little-known band called Led Zeppelin as their opening act. Many fans and critics have noted the similarities between Spirit's song 'Taurus' and the intro to Zeppelin's 'Stairway to Heaven,' which appeared several years after.

After the release of their landmark fourth album, 1970's 'Twelve Dreams of Dr. Sardonicus,' the original lineup of Spirit fell apart. Cassidy would continue with the group through various lineups over the course of decades until Randy California's untimely drowning death in Hawaii in 1997. After that he continued to play with surf musician Merrell Fankhauser until he retired from performing. In later years he was also involved in acting, appearing in '2010' and 'The Escape Artist' on the big screen, and twice in minor roles on the television soap opera 'General Hospital.'

Spirit bassist Mark Andes paid tribute to Cassidy in a Facebook post Thursday, writing, "RIP Ed Cassidy, one the worlds greatest drummers...loved you cass..." and posting a picture of the pair together.

Bob Irwin produced a series of Spirit re-masters, starting at Sony in the '80s and eventually carrying over into vinyl re-issues on his own label, Sundazed Records. He recalls his friend and colleague fondly. "What can I say, other than Ed was a friend, a consummate professional and mighty-ass drummer," he tells Ultimate Classic Rock in an email. "He was close - and stayed close -  to his entire body of work, and certainly took great pride in the band's recordings and accomplishments."

Hear Spirit Perform 'I Got A Line on You'

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