In the summer of 1968, Miles Davis released Miles In The Sky. Called a "transitional album" by critics, the opening track, "Stuff"—featuring Herbie Hancock on Fender Rhodes—marked Davis' first tentative step, after decades as an acoustic artist, toward going electric.
Later that year, Davis released Filles de Kilimanjaro, which went further, and showed the influence of his then-fiancé, Betty Mabry. The couple married in fall '68, but divorced a year later. Mabry—an important musician in her own right—released three epic funk albums as Betty Davis in the mid-'70s. But while they were still together, Mabry turned Davis on to contemporary artists like Jimi Hendrix and Sly & the Family Stone (she also convinced him to update his wardrobe), and the album's final track, "Mademoiselle Mabry," lifted—or maybe it's better to say, borrowed—the main theme from "The Wind Cries Mary," from Hendrix's debut, Are You Experienced.
"The music I was really listening to in 1968 was James Brown, the great guitar player Jimi Hendrix, and a new group… Sly & the Family Stone, led by Sly Stewart from San Francisco," Davis says in his autobiography. "The shit he was doing was badder than a motherfucker, had all kinds of funk shit up in it. But it was Jimi Hendrix that I first got into when Betty Mabry turned me on to him."
Davis' landmark 1970 double LP Bitches Brew, released on the heels of In A Silent Way, was his second album to fully embrace electric instruments. Bitches Brew hit the jazz world like an atomic bomb. It was groove-centric, dissonant, and unconventional. It was also something of a hit, peaking at 35 on the Billboard 200, and it would eventually go platinum.
Davis then took another cue from Hendrix, to further electrify his trumpet.
In 1971, he released Live-Evil—with Michael Henderson, poached from Stevie Wonder's band, on bass—and added a wah wah pedal to his signal chain for the first time. That effect transformed his sound and defined his tone for the rest of the decade.
"I was using the wah wah on my trumpet all the time so I could get closer to that voice Jimi had when he used a wah wah on his guitar," Davis says, also in his autobiography. "I had always played trumpet like a guitar and the wah wah just made the sound closer."
Davis' appreciation for the guitar stretched back at least as far as 1960's Sketches of Spain, which included Gil Evans' new arrangement of a classical guitar masterpiece, "Concierto de Aranjuez." Davis struggled during the recording sessions to capture the right feel, but ultimately praised Evans' flamenco-hued work: "He made that orchestra sound like one big guitar."
The electrified wah was a different beast entirely, and it brought a whole new energy to Davis' playing from Live-Evil forward.
"He was really into it," saxophonist David Liebman says about Davis' embrace of the wah. Liebman was in Davis' early-'70s band and appears on the albums On The Corner, Dark Magus, Get Up With It, and a number of others released later. "As you can see in the videos, he's hunched over so his foot could be in a certain position. Sometimes they show pictures of his feet and he wore crazy shoes, but he was really into it. It wasn't a perfect machine for the trumpet. There were times when it was a little sketchy as far as its working, but if you listen to him without any judgment, it was actually pretty interesting."
Davis' use of the wah is also somewhat ironic, as the original wahs took inspiration by the trumpet. Vox was the first company to have success selling them, and its model was named for trumpeter Clyde McCoy.
"Apparently Vox management saw lots of potential in this new gizmo, and it was subsequently introduced as the Clyde McCoy wah-wah pedal," Art Thompson wrote in a May 1992 article for Guitar Player. "Clyde was actually a trumpet player who had asked Vox for a device that could simulate the sound of a muted trumpet for use with a keyboard. These early pedals were manufactured in Italy and have a picture of Clyde on the bottom. They were distributed in the US by the Thomas Organ Company. Later variants featured Clyde's signature only."
In the late '60s, as guitarists embraced the devices, Vox dropped their association with Clyde McCoy, and created a number of variants as the company and its distributor worked to meet the growing demand.
Some Vox wahs of this era were made in Italy, others in the US, and you will find fans of each that praise particular models for their specific inductors, capacitors, and potentiometers. Geoffrey Teese, a vintage Vox expert, told Eric Kraft, a writer and guitarist that once played with Sly & The Family Stone, that there was a huge leap between the Clyde and the next model, the US-built V846, but that others that immediately followed were relatively similar to each other.
"The Vox/USA V846 changed much more than just the inductor. Everything but the very basic resistors were changed, making the V846/King Vox Wah/CryBaby virtually an entirely new pedal," Teese said. However, because manufacturing processes were not standardized, these post-Clyde US- and Italian-made models could all have audible differences between them, even if they shared a name.
Davis' wah—see a closeup in the video above at the 10:51 mark—was the King Wah. As you can hear, it imparted a quacking character to his trumpet's tone.
At their most basic level, all wahs are a kind of resonant filter, sharpening a peak of frequencies that moves through the bass-to-treble spectrum as a player swivels their foot. The abrasive guitars, electric pianos, snares, and cymbals of this new era of funk-inspired jazz were all competing for sonic space. Davis used the added attack of the King Wah to pierce through the chaotic jams and bring his voice back to the fore.
In 1972, Davis brought his wah into the studio to record On The Corner. On The Corner expands on the themes first introduced on Bitches Brew, except that the grooves are more repetitive, minimalist, and funky. It also features an expanded ensemble that includes electric sitar, tabla, and other assorted percussion.
"On The Corner, which ran a cast of thousands, was like a Cecil B. DeMille production," Liebman says about the album's recording sessions. "Herbie, Chick Corea, John McLaughlin, Don Alias, Jack DeJohnette, Billy Hart, Collin Walcott—it's amazing I remember the names—everybody had their little scene in the room where Miles recorded. Everyone was plugged in direct except the drums, congas, and tablas. Bass, piano, and the guitars—all those guys were plugged into the board and I couldn't hear anything in the studio. I couldn't hear the key. Nobody gave me headphones. But like so many things in life, it's sometimes strange the ways things happen, and I just had to guess the key, and I got it right."
But On The Corner was an anomaly, and aside from the sessions that made up the compilations Big Fun and Get Up With It, most of Davis' output from this period was live. Dark Magus, released in 1977—and only in Japan—was recorded live at Carnegie Hall in 1974. By that point, Davis had guitarists Pete Cosey and Reggie Lucas, as well as drummer Al Foster, and percussionist James Mtume in his band, who, along with Henderson, formed his core working group for the next few years. Keyboards, except when Davis played them, were out as well.
"That was definitely one of the loudest band that I ever heard," Liebman says about Davis' Dark Magus-era band. "I've played in many rock bands, but this was a very loud band. I believe I was also using effects at that point as well. I had an orange box, which was a chorus, and an Echoplex."
As the '70s wore on, Davis retreated into a dark period, usually referred to as his "retirement," of drugs and sex—compounded by numerous health issues—and didn't record new material until his comeback in the early '80s. But while he was away, his post-Bitches Brew, wah-inflected work—generally not well-received at the time of release—began to take on a life of its own. Younger players absorbed his music from that period and many cite it as a major influence. That list includes everyone from the Beastie Boys to Material (whose core of Bill Laswell, Michael Beinhorn, and Fred Maher went on to become major producers in their own right) to experimentalists like Henry Kaiser, and many others.
Davis returned in the '80s with a new, young band—Foster was the only holdover from the '70s—and began a new chapter of his ever-evolving sonic adventure. He embraced slap bass, nurtured the careers of a number of exceptional guitarists, and even reintroduced keyboards into his lineup.
However, times were changing, and by then he stopped using the wah.