Way back when rock 'n' roll was countercultural -- before the members of the Rolling Stones were anywhere close to 50 years old, much less celebrating their 50th anniversary together -- the genre tended to emphasize rather than bridge generational divides.
So when the experimental group Spirit formed in the late 1960s, it was different not just for the way it fused jazz and rock, or the way it mixed psychedelia with a particularly tight backbeat. It was also different because its drummer was the 44-year-old stepfather of its 16-year-old guitarist.
That drummer, Ed Cassidy, died Dec. 6 in San Jose, Calif. He was 89. The cause was cancer, his former wife, Beverley Cassidy, said.
By the time Spirit formed in 1967, Mr. Cassidy had already had a notable and diverse musical career. He had played with jazz musicians including Dexter Gordon, Chet Baker, Gerry Mulligan and Cannonball Adderly and had formed a folk-blues group with Taj Mahal and Ry Cooder called the Rising Sons.
Spirit released more than a dozen albums from 1968 to 1996, but it was the first work that was the most influential and critically praised.
Its biggest hit and only Top 40 single, "I Got a Line on You," was released in 1968; the band was also celebrated for its adventurous 1970 album, "Twelve Dreams of Dr. Sardonicus."
That record included the song "Mr. Skin," which was the nickname Mr. Cassidy's fellow band members had given him in honor of his shaved head.
Bob Irwin, the president and owner of Sundazed Records, which has reissued many Spirit albums and also released previously unissued tracks, said the band's early recording sessions were "kind of like a jazz history lesson" in which Mr. Cassidy nurtured his much younger colleagues.
"Ed always encouraged them to color outside the box, to take chances onstage, to play to the best of and beyond their abilities," Mr. Irwin said.
Edward Claude Cassidy was born May 4, 1923, in Harvey, Ill.
His family moved to Bakersfield, Calif., when he was a young boy. He took interest in the drums after listening to musicians who played clubs in the area in the 1930s.