There was something else that Swallow noticed at that Beatles concert. "I was impressed by their posture toward their public — they were extending themselves to us in a way that I admired and wanted to emulate. They were addressing us, but with a lot of dignity, without any condescension on one hand or groveling at our feet, either. They were tremendously contained and dignified." What's more, the white English band "talked openly about their debt to black American music."
Other revelations were to come. The Burton Quartet often traveled cross-country, and Swallow says he first heard Jimi Hendrix on the radio in a VW bus crossing the Golden Gate Bridge — a moment he compares to "Paul on the road to Damascus." The quartet grew their hair, donned beads and bellbottoms. Like other jazz acts, they were regular openers at Bill Graham's San Francisco Fillmore Auditorium for bands like Cream and the Electric Flag. Swallow: "It was impossible for me to deny that I was listening to music of real value and real meaning for its time. And I'd begun to question whether the jazz music I'd grown up admiring so much was still congruent, still as germane in the late 1960s as it had been in the late 1950s." As he wrote for the band, Swallow consulted its guitarists — Coryell, and later Sam Brown, John Scofield, Mick Goodrick, Metheny — to translate "guitar-neck vocabulary" into themes that could become content for jazz improvisation. Burton himself had recorded as a teenager in Nashville with country guitarist Hank Ballard and, later, Chet Atkins.
But there were still more changes in store for Swallow. At a trade show in Chicago, Burton was playing demonstrations for the Musser vibraphone company with Swallow accompanying — 20-minute sets with 40-minute breaks. Over the course of a couple of days, Swallow had visited every booth — including the Gretsch drum display — while resolutely ignoring electric guitar. Finally, having exhausted every other possibility, he snuck into the Gibson booth. "It was like going to a dirty movie or something. I didn't want anyone to see me." He picked up a Gibson EB2 semi-hollow-bodied electric. "I fell in love, the feeling hit me like a ton of bricks. It wasn't something I did, it was something that happened to me. And my immediate impression was: 'Oh, shit! I'm in deep trouble here! This could really make life difficult.' My hands and brain were in furious disagreement."
With the possible exception of Monk Montgomery, whom Swallow hadn't seen, no one was playing electric bass in jazz — his heroes were acoustic-bass masters like Wilbur Ware, Percy Heath, and Doug Watkins, and guitarists like Charlie Christian and Jim Hall. "I was really apprehensive about what this switch would mean, and deeply hopeful that the people I loved to play with would understand." Fortunately, Burton was one of them, as well as Coryell and later the drummer Bob Moses, another crucial member of the Burton bands. But the big difference was Roy Haynes — an older-generation musician who'd played with everyone from Lester Young to Charlie Parker and Thelonious Monk. Haynes "punched our ticket," says Swallow, approving the direction they were taking.