Hooligans On tour!

Both acts have built 21st-century careers, working as performers, producers and songwriters, taking their time between albums, but keeping themselves on listeners’ radar through their productions and guest appearances — showing up for a chorus or rap on other stars’ singles.

The crowd at the Hollywood Bowl Saturday night — the first of two sold-out Bruno Mars/Pharrell Williams shows — was diverse, even for Los Angeles. There were boxes of stylish double-daters, gaggles of single ladies decked out for a night on the town, families who brought the kids not to save on a babysitter but because this was a rare pop concert where both generations were excited to be there. (And if how many kids are dressed like the headliner is a legitimate metric of success, Bruno Mars is doing very well; during a trip to the concession, I saw at least a dozen kids, from preschoolers to tweens, sporting black and gray houndstooth vests and Mars’s signature broad-brimmed hat rakishly perched on their heads. In comparison, Pharrell’s oversized Dudley Do-Right Stetson was nowhere to be seen.)

Pharrell took note of the audience’s age range and admitted he was trying to tone down the language because of all the kids in the house. (Gwen Stefani, who joined Pharrell on a riotous “Hollaback Girl,” apparently did not get the memo, as she retained the song’s PG-13 lyrics, reminding the crowd that “this shit is bananas! B-A-N-A-N-A-S!”)

What brought out the celeb-studded crowd (also a diverse group, including Quincy Jones, Jeffrey Katzenberg, Paul Anka, Quentin Tarantino, Howie Mandel, Jessica Alba, Kaley Cuoco, Lea Michele and Zac Efron) were the two most successful pop-soul figures working today, in a line of American music that can be traced back to Motown. But where Motown famously called its recordings “The Sound of Young America,” Mars and Pharrell do it one better: they’re making “The Sound of America.” What made the show fascinating were the different routes they take to get there.