Imagine Dragons are a perfect blend

Imagine if you were Dr. Simon Cowell working in your top-secret laboratory trying to create the perfect rock band for 2013.

You'd probably want a taste of Mumford & Sons (folk-rock) and Coldplay (polished arena rock) for mass appeal, a little Vampire Weekend (Afrobeat pop) and Passion Pit (synth pop) for hipness, a dollop of dubstep and big beats for dancing, emotional but often vague lyrics with big choruses for singing along, a helping of the madman drumming of Blue Man Group for rhythmic showmanship, players who went to a top-notch music college and a charismatic, standout frontman.

Cowell didn't whip up Imagine Dragons. But, after four years of woodshedding and touring, the Las Vegas quartet organically found the right ingredients that have made them America's biggest rock band of 2013 — only Mumford, from the U.K., has sold more recordings.

After playing a few smaller shows in the Twin Cities at the Triple Rock, Varsity and Basilica Block Party, Imagine Dragons stepped to the throne Monday night in front of a jam-packed crowd of 5,500 at Roy Wilkins Auditorium. It was the group's final U.S. show before heading to Mexico, Australia, New Zealand and Europe.

The Dragons, augmented with a keyboardist, hit the stage looking like their moniker might be Plain Black T's, but they instantly transformed into what could be called Bang the Drum Loudly.

That's what the Dragons do best — put the organic drum beat into mainstream rock/pop. Those loud drums are what set them apart from so many rock/pop acts with similarly sounding singers with forgettable names like Matt, Philip and Dan. But the Dragon's Dan Reynolds didn't come from central casting.

He's a 26-year-old 6-foot-4 former Mormon missionary, who carried on like part punk and part earnest new dad, hammering away at one of five drum setups — from a giant taiko drum 6 feet in diameter to a small drum kit. And he has a voice with range, percussive phrasing and enough emotional nuance to get young women to swoon to his ballads and medium tempo rockers.

More typically, Imagine Dragons offered more intricately crafted music during their 90-minute set. "Underdog" was a musical mutt that melded reggae with an Eastern synthesizer line. "30 Lives" felt like a pretty Irish folk ballad while "On Top of World" was a Caribbean explosion. "Demons," the band's current radio hit, came across as sing-songy Coldplay does U2. "It's Time," took its Mumford-like mandolin and hand claps and created a giant singalong.

Then there was "Radioactive," one of the year's biggest radio smashes. Find the dubstep beat, turn up the fuzz tone on the guitars and cut Reynolds loose. Not only did he bellow like Bono but he turned into a hyperactive little drummer boy leading a full-on drum onslaught with the other Dragons. It felt like the right mix of craft, earnestness and urgency — and the most resourceful and imaginative use of drums in concert since Fleetwood Mac trotted out the University of Southern California marching band for "Tusk."

Not only would Dr. Cowell have been proud of Imagine Dragons, he would have been envious that he doesn't have a finger in rock's biggest American pie of 2013.

set lit: www.startribune.com/artcetera