Justin Bieber Concert: The kid Connected At The Prudential Center

Even before the first note was played, they were on their feet, dancing and clapping, singing and hollering, making a handsome racket for their teenaged idol.

And that was just the parents.

Say what you want about Justin Bieber, but give the kid this: He connects. His show at Prudential Center in Newark on Saturday — a house too crowded for cynicism — was an exercise in sustained ecstasy.

For 80 minutes, concertgoers at the sold-out arena did whatever the pop star asked of them: screaming on command, dancing in (and sometimes atop) seats, waggling glow sticks and cell phones, and singing back the choruses of YouTube favorites. When Bieber floated above the crowd in a heart-shaped cage, thousands of arms reached desperately in his direction.

Bieber is an upstart popster with a massive fan-base, but it can be hard to find anyone outside of the cult who will cut him any slack. For many adults, he has become the hit radio version of Barney the purple dinosaur: a crooning symbol of the disconnect between child consciousness and sophisticated tastes. Grown-ups take pride in not getting Bieber’s appeal. Indeed, Bieber seems mainframe-designed — the possessor of unearthly composure, manufactured innocence, and slightly overwhelming youthful enthusiasm.

But if Bieber comes off as an unsinkable automaton in his video clips, the problems he faced at Prudential Center were altogether human ones. His voice is changing, and he fought to recapture the silky delivery that distinguished his early hits. He strained for some high notes, and he was occasionally shrill. Bieber was also battling a cold (indeed, he cancelled the next night’s show in Syracuse) and sounded congested on quiet acoustic numbers such as “Favorite Girl.” Also, Bieber’s technical crew let him down from time to time: The pop star was handed a slightly out-of-tune guitar, and when he took a drum solo, his kit was poorly mixed.

The singer didn’t let any of that shake him. Instead, he got stronger as the show went on, hitting the finish line in full stride. The final stretch of the set — the upbeat “One Time,” a breakdancing interlude in which Bieber participated, the earnest “That Should Be Me,” the inane but oh-so-pleasurable “Eenie Meenie,” and the dramatic “Down to Earth” — was an exhilarating trip on a Ferris wheel. Adrenaline is an amazing thing; beyond that, the professional Bieber proved that he could take a hit, or several, and keep on rocking.