Ed Ward has been thinking about rock music for a long time. He's written about it since the 1960s, for about as long as serious rock criticism has existed. In 2016, Flatiron Books published the first volume of Ward’s "History of Rock & Roll," planned as a trilogy. It covered the years 1920 to 1963, just as the Beatles started to make an imprint on the world consciousness.


The second volume of the project — titled, as you might imagine, "The History of Rock & Roll, Vol. 2: 1964 to 1977" — moves from Paul, John, George and Ringo to the death of Elvis Presley. The old god is dead, punk rock is not yet a thing, and if you are, as Ward is, focusing on rock as popular music, rock is still a monoculture, more or less.


"The introduction of the Beatles is the moment when the modern popular music structures started getting erased, because the Beatles were so much more popular than what came before," Ward says. "They weren't people who just disappeared after a few hits. They were phenomena like Elvis, and yet so much bigger."


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Ward, for his part, was a folk music fan, which also is part and parcel of this moment.


"The folk revival was the basis of so much of the next generation's music," Ward says. "The San Francisco sound was pretty much 100% folkies. And Dylan became this thing called a singer-songwriter, which was a fairly new phenomenon and one of the streams that fed into the mainstream of popular music."


What Ward comes back to again and again in this work is the idea of the "audience-created phenomenon." Take, for example, Dick Dale, whom Ward characterizes as "phenomenally important." Dale, a stunning guitarist who all but invented surf rock, created both a band and an audience out of his fellow surfers.


"The audience would come to see Dick Dale and the Dell-Tones, and they recognize those guys," Ward says. "They were the same guys they were surfing with earlier in the day."


The Beatles had a similar effect on the audience. Ward says they were Liverpool kids playing at their neighborhood club, the Cavern: "So people went to go see them, and other bands were formed because they wanted to be Beatles. People from the audience created these new forms of popular music, and then the industry attempted to market it."


Ward's byline has appeared in such legendary publications as Crawdaddy, Rolling Stone and Creem, as well as the American-Statesman, where he was a music critic from 1979 to 1984. But he admits there were a few artists whose significance he simply missed at the time.


"The most striking example of that was David Bowie, who I had completely missed early on," Ward says. "I think that was a function of age, honestly. Bowie as a phenomenon was a generational thing, and I just missed it. The lightbulb going off was listening to ‘Ziggy Stardust’ again and hearing ‘Give me your hands ’cause you’re wonderful’ (from the song ‘Rock ’n’ Roll Suicide’). And then I heard that done live, and there was an uptick in the amount of power that was being broadcast from the stage. You could hear the audience accepting that challenge."


As for a potential third volume of "History of Rock & Roll," Ward says he would likely start with the rise of what music critic Robert Christgau called "semi-popular music," the sort of thing that, as Ward says, "everybody you knew liked and didn't chart or sell." He also would start with Eddie Wilson needing a place to put on Austin proto-psychedelic oddballs Shiva’s Headband, whom Wilson was managing at the time, which lead to Wilson founding the Armadillo World Headquarters.


"Austin was one of America's most amazing semi-popular scenes," Ward says. "If you live in Austin, it’s kind of taken for granted. You know a lot of the names associated with it, but most people don't." Ward also plans on addressing such topics as reggae, progressive country, heavy metal and punk.


And where does it end? "Napster," Ward says. "The triumph of the people who cut the gates at Woodstock. They won. They said, ‘This should be free; it’s ours.’"


And, as Ward notes with no little irony, about six hours after "The History of Rock & Roll, Volume 2: 1964–1977" hit the stores, a friend sent him a link to a site at which one could download the book for free.