LOS ANGELES — When Pink Floyd first took its concept album "The Wall" to the concert stage more than three decades ago, even lead singer and chief songwriter Roger Waters couldn't have imagined a day when rock music might get any bigger.

LOS ANGELES — When Pink Floyd first took its concept album "The Wall" to the concert stage more than three decades ago, even lead singer and chief songwriter Roger Waters couldn't have imagined a day when rock music might get any bigger.

But 32 years later, his magnum opus about the battle between individual freedoms and authoritarian oppression has magnified beyond Waters' own expectations of yore. Now the man who once excoriated the voluminous expansion of the rock concert experience has helped institutionalize it. "I famously hated playing to large numbers of people and playing in stadiums," Waters, 68, said from a tour stop in Austin, Texas, earlier this month.

"The outdoor version, which we developed for South America and which is so much bigger than the arena shows," the British rocker said, "illuminates the piece in ways we can't and couldn't do indoors."

For instance, in the arena version, the metaphorical wall that is gradually built through the course of the evening typically spans about 200 feet. At stadiums, it stretches out to around 500 feet. "It's a new concept of how to produce rock 'n' theater on a great big football field," Waters said. "We have technology available that's so profoundly superior to what we had 30 years ago. You can be 200 yards from the show and still be completely engaged with what you're seeing."

The recent South American tour of "The Wall" broke attendance records there — nine sold-out shows at River Plate Stadium in Buenos Aires trounced the previous record of five at the same venue held by the Rolling Stones — and it's also been among the top-grossing concert draws in North America since he resurrected and updated the show in 2010.

Since bringing "The Wall" back, Waters has done 150 performances that have grossed $218 million in 27 countries. It would be tempting to think that by now "The Wall" is a well-oiled machine with every element solidly in place down to the last microsecond of music and pixel of imagery. "I take a hard drive straight home from every gig and then look at it the next day or the next night, and I write notes," he said. "I don't think there's been a single day where I haven't changed something."

Conceptually, too, the show has grown from its origins as a polemic largely about the angst of one particular rock star.

"The new incarnation of 'The Wall' is completely unlike the 1980 version," he said. "It's developed into being much more of an international polemic, and it's also much more moving," he said, referring to images, many submitted by fans around the world, of family or friends killed in various wars over the past century. "In those days it was about the internal struggle of me, when I was younger. It's now much more about everybody else, much less about me, and what's going on in politics, communication and all the stuff I care so deeply about. In consequence, lots of people in the audience weep. That makes me very happy, to be able to engage people to where they can empathize with others to the point where they weep."