19. “Ostinato (Suite for Angela),” Herbie Hancock, from Mwandishi (1971)

In October of 1973, pianist Herbie Hancock became an international superstar: His album Head Hunters was a monster crossover hit, selling over a million copies. Sporting a day-glo purple, pink, and yellow cover, the album buzzed with the overdriven staccato sounds of Hancock’s electric clavinet alongside Harvey Mason’s dry, in-the-pocket drumming; Paul Jackson’s streamlined funk bass lines; and congas, chanting, and pygmy flutes courtesy of percussionist Bill Summers.
 
The album’s infectious, radio-friendly appeal was no accident. “I was beginning to feel that we were playing this heavy kind of music,” Hancock explained in 1997, “and I was tired of everything being heavy. I wanted to play something lighter.”
 
That “heavy” music had appeared over a trio of ambitious albums at the decade’s start: Mwandishi (1971), Crossings (1972), and Sextant (1973). “Ostinato,” the lead-off track for Mwandishi, was dedicated to then-imprisoned political activist Angela Davis. It sports futuristic electronic effects and dense tangles of percussion, and is anchored by a trance-inducing, unchanging bass groove—all of which superficially could describe the sound of Head Hunters, too. But it’s set in 15/8, an off-kilter time signature that defies listeners to bob their heads or tap their feet, much less get up and dance.
 
“I wanted to write a tune with an underlying rock beat, but using it in a more open way than usual,” Hancock explains in composer Bob Gluck’s 2012 book, You’ll Know When You Get There. “Having 15 beats in a bar automatically sets up a little tension, because just when you think you’ve got it figured out, it eludes you. At the end of each bar we all hit a phrase together, and that’s a release.”
 
“Ostinato,” then, was an attempt to play with rock and funk conventions yet challenge both his band and his audience—and it suggests a middle ground between music-as-artistic-gesture and music-as-unrepentant-groove. By the time he recorded Head Hunters, though, Hancock was apparently done with intellectual gamesmanship and ready for a full-throated embrace of the pop culture moment.