In 1973, Herbie Hancock, a virtuosic jazz dissident, stomped out an entire history of sound when he walked out a bassline on a modular synthesizer. This was not someone’s upright acoustic bass played with calloused fingers, it was preprogrammed on a circuit board obscured inside a small wooden box, amplified by some hidden electrical process. And it wasn’t one bassline crawling out of the speakers, it was two, dubbed on top of each other, split across the stereo field, blasphemed onto what was ostensibly a jazz recording in post-production.

For purists, it was just another heretical element on another album of heresy from yet another jazz pioneer turned iconoclast. The afterimages of Miles Davis’ blinding turn toward the electric music a few years earlier were still being processed by audiences, players, and critics alike. Hancock, having played keys for six years with Miles Davis’ Second Great Quintet, had his own gauntlet to throw. Inspired by the power he saw in James Brown and Sly & the Family Stone, Hancock wanted to quit wafting in the rarified air of acoustic and avant-garde jazz. “I was not trying to make a jazz record,” Hancock said later. He wanted to get low, down to the floor, through the earth. He wanted to make a pure funk record. Instead, he made Head Hunters.

A year before Hancock plunked out that bassline, his woodwind player, Bennie Maupin, sat among the sold-out crowd at Los Angeles Coliseum for Wattstax, a 1972 benefit concert sometimes referred to as “Black Woodstock.” Every marquee artist from the iconic Memphis soul label Stax performed that August afternoon—from the Staple Singers to the Bar-Kays to Isaac Hayes, who closed the concert wearing a gold chainmail cape. The eight-hour show meant to “give back to the community” in the primarily black Watts neighborhood, which had been torn by riots seven years earlier. Tickets were $1, and the security force was entirely black and unarmed. With over 110,000 in attendance, it was then the largest gathering of African Americans in one place since the civil rights March on Washington in 1963.

Maupin, a 32-year-old jazz woodwindist nonpareil from Detroit, had been playing with Hancock for the previous three years on a trilogy of experimental albums known as Hancock's Mwandishi period, from the Swahili name for “composer” that he had adopted at the time. Mwandishi (1971), Crossings (1972) and Sextant (1973) were lofty, sometimes electronic excursions, all influenced deeply by jazz’s big extinction event, Miles Davis’ 1970 album Bitches Brew. The Mwandishi group would sometimes sit in the tour bus and listen to records by German electronic music pioneer Karlheinz Stockhausen at Hancock’s request. In the studio they were incorporating the vanguard production techniques of Bitches Brew, which were verboten in traditionalist jazz circles: extensive editing, amplified instruments, two drummers, overdubs, synth loops. Having played bass clarinet on Bitches Brew, Maupin served as real connective tissue from the most infamous jazz record to the second most infamous jazz record: Head Hunters. When Hancock disbanded the Mwandishi group in search of a new sound, Maupin was the only member he kept.

The heady strains of the Mwandishi era were a lot more highfalutin than the music Maupin witnessed at Wattstax, though. As the bands grooved to soul, R&B, and funk onstage, Maupin watched a group of young kids dancing the funky robot, popping and locking their joints at right angles. “I just started to hear in my mind melodies centered around that kind of movement,” Maupin later said. The melody: two little hitches, a staccato double-tap, followed by a bluesy riff down a minor pentatonic scale. Tributaries of jazz history flowed through Maupin, who had played with hard bop greats like Lee Morgan and avant-garde pioneers like Pharoah Sanders in the previous decade. But at Wattstax, he was tapping into a broader, more popular, more body-focused black experience. The music Hancock was plotting, like the melody Maupin imagined, drew from the politics of the Watts Riots and Black Nationalism and the counterculture, but also the beat, the one, the groove that made kids want to free their mind and dance.

When the concert let out, Maupin brought his riff idea based on the funky robot back to Hancock at a rehearsal space in Los Angeles, where he fed it to the newly assembled Head Hunters lineup. Maupin didn’t use the woozy timbre of the bass clarinet but rather the gritty R&B sound of the tenor sax. The upheaval of avant-garde and the donning of funk all poured into “Chameleon,” an indefatigable 15-minute track that staked a new epoch for jazz the minute Hancock plunked out its bassline. Nothing was what it seemed: the bassline was a synth; the guitar-sounding riff was a bass, played by Bay Area funk stylist Paul Jackson in the altissimo register. Hancock plays his clavinet like Hendrix comping time with a wah-wah pedal. The in-demand R&B session drummer Harvey Mason plays in a straight-eighth funk feel, like Clyde Stubblefield did behind James Brown. “Chameleon” slid in and out of the downbeat of ’70s funk, the looseness of cool jazz, the musical modes of R&B, all while drawing upon the rhythms of Anlo-Ewe and Afro-Cuban drumming, black counterculture, and the vanguard of modular synthesizers.

All this blending of traditional instruments and technology, of black American and African sound, was reflected on the album’s cover: Next to Maupin, there’s Jackson holding a Fender bass; Mason clutching a snare; a virtually unknown percussionist from the Bay Area, Bill Summers, holding gourd rattles. Front and center is Hancock, his face covered with something resembling the ritual kple kple mask worn by the Baoulé people of the Ivory Coast—the eyes, however, are radio knobs, and the mouth is a VU meter, an electronic tool for measuring loudness.

A satellite view of Head Hunters reveals a vast bazaar of cultures and genres, a complicated interchange of artistic and personal histories. Recorded in a single week and released shortly thereafter, on October 13, 1973, it spent 42 weeks on the Billboard chart, becoming the first platinum-selling jazz album, as it was being slammed by critics as a rapacious commercial move. It was an album that captured jazz as it broke out and mingled with America, appealing both to the Wattstax crowd and to white suburbia. “Sure I’m getting a bigger white audience,” Hancock said a year after the album’s release. “But I’m also getting a big black audience, which I never had...I’ve finally been able to come out with some music the general black public can relate to.”

By 1973, rock, pop, and R&B had been cannibalizing the jazz audience for over a decade. In the wake of Miles’ electric albums, jazz fusion groups like the Mahavishnu Orchestra, Weather Report, and Return to Forever tried to capture both sides of the aisle. The walls were crumbling between the haughty air of jazz and what was being played on commercial radio. Taking a cynical view, jazz historian Grover Sales put it this way: “Some bored rock artists had been gravitating towards jazz because they were bored, while jazz players dallied with rock to recapture their dwindling audience.” In the eyes of purists, fusion groups had poisoned the sanctity of jazz, for reasons ranging from crass commercialization of what was once a pure art form to something more pernicious. Head Hunters co-producer David Rubinson said that “jazz fusion meant... white people playing black music.”

But Head Hunters avoids the fussy, technical chops of those fusion groups, and instead sinks deeply into funk. In a 1985 interview, Hancock revealed his mindset going into making a pure funk record: “When I heard [Sly & the Family Stone’s] “Thank You (Falettinme Be Mice Elf Agin),” it just went to my core. I didn’t know what he was doing. I mean, I heard the chorus, but how could he think of that? I was afraid that was something I couldn’t do. And here I am, I call myself a musician. It bothered me…I decided to try my hand at funk.”

Like jazz, funk was, at its genesis, a wholly black and political genre, tempered in the Black Power movement of the ’60s and carried forth into the Nixon era by Brown, Sly, George Clinton, Curtis Mayfield, and others. For all of funk’s nastiness and ecstasy, its subversive emancipation of mind and ass, its no-pretense elemental nature, Rickey Vincent, in his 1995 book on the history of funk, lands on a long-view definition. He writes that funk is “...an aesthetic of deliberate confusion, soulful behavior that remains viable because of a faith in instinct, a joy of self, and a joy of life, particularly unassimilated black American life.” The black roots of Head Hunters create this underground communion of joy, a funky celebration of all that is modern and ancient.

Funk was psychedelic dance music, working-class rebellion, something elusive and unattainable to a mainstream white audience. And as always, mainstream America drank deep from this new well of underground black music. It made Hancock rich—and the numerous times “Chameleon” and “Watermelon Man” have been sampled in hip-hop only made him richer. But it was a sticking point for critics who called the great jazz piano player a pop sell-out. Members of the jazz cognoscenti did not want the hem of their garments sullied with the commercial slop of popular music. In conversation with famous jazz grouch Wynton Marsalis, Hancock defended Head Hunters not as an album that set out to make money, but an album that happened to make money. “Look I’d like to have a Rolls-Royce,” Hancock said, “but I’m not trying to set myself up to get a Rolls-Royce.”

It is impossible to capture the whole external life of the galactically important Head Hunters, what it touched, how it functioned, its shape in society, its place on the great cosmic map (though musicologist Steven Pond approaches totality in his peerless 2005 book on the album). Truthfully, though, Head Hunters doesn’t confer great importance by the sound of it. It doesn’t scream “cash-grab,” or signal a fissure in jazz, or really exist in any of the contexts that surrounded its release almost five decades ago. The microbial funk of the album, its living power, lies below all that.

Head Hunters states its intent in its name: The music will blow open your skull the second you press play, the instant the bassline from “Chameleon” comes out of the speakers in full stereo sound. And if that doesn’t move you, how about when Harvey Mason comes in with the funkiest drum part in the history of drumming, a groove even Hancock said he had never heard before in his life, that snare hit coming just before the two, the kick drum so dead and relaxed, are you kidding me? Head Hunters rightfully belongs to the Library of Congress as one of our nation's most treasured recordings, sitting there, smoking, untouchable, a factory of winces and hoooos.

Hancock’s idea for Head Hunters involved making a funk album with players who brought many other worlds to the table. Mason was an R&B drummer who played deep in the pocket, but he didn’t just sit on one pattern, he tugged and pulled at it throughout the song, a tailor constantly adjusting the fit and feel. Then there’s Summers’ famous solo on beer bottles, pennywhistle, shekere, handclaps, and falsetto ad-libs at the beginning of “Watermelon Man,” a tune carried over and radically reinterpreted from Hancock’s earlier career as a more traditional jazz player. This section is an adaptation of the traditional calls of Ba-Benzélé pygmies of Central Africa, an effort by Summers “to bring up the level of appreciation of the African experience.” With a fat Fender sound, Jackson plays the best bassline on the album—better even than “Chameleon”—defining the one and creating the syncopation outside of Summers’ nest of percussion.

Maupin doesn’t just riff around on the blues scale; on the vastly underappreciated “Sly,” he goes far out, squeaking and running high and low on the soprano sax, bringing his ’60s avant-gardism back into the soundscape, all on a song named after funk master Sly Stone himself. “Sly” may not have the cultural cachet of “Chameleon” or “Watermelon Man,” but it is the album’s true synthesis of funk texture and jazz feel. When the song shifts grooves around the two-minute mark, Hancock starts comping on his clavinet in stereo, Summers starts an Afro-Cuban groove on the conga, and Mason loosens his wrist on the snare to give Maupin as much room as he needs. By the time Hancock gets to his solo on his Rhodes, the song feels both impossibly free and tightly wound.

Finally, Head Hunters cools down with “Vein Melter,” the corpse pose, a psalm on death written for a friend of Hancock’s who died of a heroin overdose. With Mason’s snare rolls every measure, it sounds like a funeral march, but Hancock doesn’t put anything to rights. He delays interment with a sneaky grin while comping on the Rhodes with preternatural chill. “Vein Melter” never succumbs to meditative repetition—you can hear the heaving breath, the residual energy of the first three songs pulsing behind it.

Head Hunters is the bond that connects unnamable forces at the center of jazz and of funk, divine aspirations and base desires, head and body. It’s foolish to try to name the spark of music like this, a parlor game better left to the comedown of an acid trip or a street preacher on his last leg. Head Hunters isn’t the god, it’s just five consummate pros jamming, with a light amount of editing and production. It’s simple, really, even accidental. About six minutes and 55 seconds into “Chameleon,” as Hancock solos on his Arp Odyssey, he lands on a four-note phrase that’s about a half-step away from the key of the song. It is a phrase that pulls your shoulders up to your ears, makes you put your hands up to your face to block the punch. It is the single funkiest, unholiest, nastiest moment on the record, and it was a complete mistake. Hancock was futzing with the manual pitch bender on the synthesizer during his solo and didn’t realign it. He was playing the wrong notes, but the right notes were coming out.

Buy: Rough Trade

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