LONDON, Ont. - The most petite Idol proved to have the biggest voice at the John Labatt Centre last night.

American Idol winner Kelly Clarkson, looking great as a classy blond and sounding more alive than she ever did on the hit TV show, needed to be that loud.

Even if Clarkson had come out ready to shout her hit Since U Been Gone with the hurricane force of her idol and fellow Texan Janis Joplin, she still might have been drowned out by the yells and screams of the hundreds of little Kellys.

The sold-out crowd of 3,200 fans in the centre's RBC Theatre format was mostly young and very female -- and totally tuned in to Clarkson.

"I don't know how I hit that last note," she said after trading increasingly piercing sonic thrills with one of her guitarists during A Moment Like This, the first number in her encore.

But Clarkson might have talking about the whole 70-minute show when she tracked down big sound after big sound.

One exception was the last number, a twin fiddles and acoustic guitar version of her big hit Breakaway, the encore finale. The unplugged version had huge singalongs from the Clarkson crowd and the Idol was beaming.

"Y'all have been awesome, y'all have been so awesome," she said before leaving for the night.

Dancing around her much taller band members, the singer was barefoot, with hip-hugging black jeans and a cute, Aerosmith top when she started. It was a complete change from her Idol wear, when she had a pop sound and look. So was the technicoloured ruffled skirt she wore later in the set.

The only Idol hangover was the set. For some reason, Clarkson was positioned under some hanging Arabian Nights lamps with flowing curtains and puffy pillows strewn about her. Maybe someone is trying to lull her back in to Idolville.

Clarkson is obviously happy to be a rocker. With her fine band blasting away behind her big voice, she moved into the tough Walk Away, from her new CD. Written in part by the Canadian rock team of Chantal Kreviazuk and her husband, Raine Maida, it had an Alanis meets Joplin feel -- a grownup greeting for all Clarkson's little sisters.

Later, she introduced the girls in the crowd -- maybe their moms knew about the blues already -- to Joplin's Piece of My Heart and B. B. King's The Thrill is Gone. Clarkson's take on Joplin is full of admiration and raw hurting power. But anyone who just heard King sing his signature tune at the downtown London arena a couple of weeks ago will know, too, that Clarkson will just have to learn it isn't always about raw power. That goes for her guitar player with the Ramones T-shirt -- always a good look -- as well.

There are songs that mean less is more and The Thrill is one of them. Clarkson deserves applause for saluting her idols and giving them a shot with an audience that doesn't know the blues.

A more thrilling cover than the King classic was the Eurythmics' Sweet Dreams.

"Did you like that?" Clarkson asked. "It is one of my favourite songs in the show. I love Miss Annie Lennox."

Clarkson won the American Idol competition in 2002. Her first album, 2003's Thankful, went double-platinum and yielded such hits as Miss Independent and A Moment Like This.

One of the second CD's hits is Behind These Hazel Eyes, a tough tune of Clarkson's she said was about a guy "she didn't like much." The audience loved hearing that.

Opening for Clarkson last night was the Texas-based Graham Colton Band. The crowd stood up when Colton, who writes songs about college dorms and rock bands said it was a good way to prepare for Clarkson's arrival.