Combine “Glee,” “American Idol,” YouTube and Billboard’s hottest hits. Add in ADD energy, imaginative vocal arrangements and varied staging and you’ll understand why Pentatonix’s performance Wednesday at the sold-out State Theatre in Minneapolis was screamingly triumphant.

The five voices in Pentatonix -- winners of NBC’s a cappella “The Sing-Off” in Season 3 and a much-viewed act on YouTube -- certainly understand their core audience: primarily young people, as young as 5 and as old as college-age. And more specifically, “choir rats,” as singer Scott Hoying called them. That described 90 percent of the audience, he observed.

Even though Pentatonix lacks a knockout lead singer (that’s true of most a cappella groups), they put on a nearly flawless 90-minute show. OK, the hyperactive lights, especially the blinding ones shining directly into the crowd, were a bit annoying; the vocal mix on the opening Daft Punk medley was terribly unbalanced, and two solo numbers were quite gimmicky (more on those later). .

But Pentatonix --whose members range in age from 21 to 25 -- had a strong sense of musicality, humor, showmanship and fun.(They gave a nice shout-out to two members of Home Free, the Twin Cities winners of Season 4 of "The Sing-Off" who were in the audience.) 

Whoever is running the show is pop smart and savvy. Change the vocal approach and visual look of every number – without changing outfits – by reconfiguring the lights and repositioning the singers (behind a white scrim, in front of scrims decorated with P, T and X, on ramps and stairways, etc). Justin Timberlake could learn from whoever conceived and staged this show.

When you’re playing to an audience of mostly clean-cut if choir-nerdy kids raised on KDWB’s hit parade, you can’t go wrong with a repertoire of knockouts by Daft Punk, Macklemore & Ryan Lewis, Lorde, Beyonce, Lady Gaga and A Great Big World.

Throw in an Imogen Heap hit for hipsters and, for parents, the Buggles’ “Video Killed the Radio Star,” Marvin Gaye’s “Let’s Get It On” (delivered to a fan, Carly, who was invited onstage) and “Evolution of Music” (a medley including such oldies as “Danny Boy,” “Boogie Woogie Bugle Boy,” “Stand By Me,” “Barbara Ann,” “Respect” as well as such modern classics as “Baby.. One More Time,” “I Want It That Way,” “Baby Baby Baby” and “Hey Ya”).

Pentatonix also offered a few originals, including the catchy “Natural Disaster” and vocally lush “Run to You” (with its close harmony ensemble vocals).

Avi Kaplan showed off his sexy/cool bass voice and some Tuvan throat singing (he’s relatively new to this Mongolian style). Kevin Olusola (whom the original Pentatonix trio discovered on YouTube) did a gimmicky solo bit featuring his stellar vocal beat-boxing and live cello (the only non-vocal instrument heard all night). While neither solo turn was remarkably accomplished, each was an entertaining change of pace that was greeted by girlish screams.

That’s not surprising for what amounts to an a cappella version of a boy-band that happens to include one young woman.