LOS ANGELES (AP) – 'American Idol' semifinalist Lilly Scott is right where she belongs.

The 20-year-old singer from Denver was among a handful of unique crooners who impressed the Fox singing contest's judges on Tuesday. The platinum-haired street musician played the guitar during her original take on The Beatles' 'Fixing a Hole' during the ninth season's first semifinal round, which featured performances from the top 12 female semifinalists.

"You come from the heart," said Kara DioGuardi, wearing a blue dress almost the same shade as the 'Idol' set.

Originality was key to dazzling the judges. Other standouts included earthy 24-year-old mother Crystal Bowersox from Toledo, Ohio, and quirky 19-year-old glass blower Siobhan Magnus from Marstons Mills, Massachusetts. A subdued Magnus transformed Chris Isaak's 'Wicked Game' while dreadlocked Bowersox pleased the panel with Alanis Morissette's 'Hand in My Pocket'.

"I think we are lucky you decided to audition for 'Idol' and be here," beamed Ellen DeGeneres.

The wisecracking talk show host, who took her place on the panel during 'Hollywood Week', was mostly serious during her first performance episode as judge, only unleashing a few barbs.

Unlike previous episodes, DeGeneres was seated at the opposite end from Simon Cowell, a move that DeGeneres mocked was prompted by the "wandering hands" of the touchy judge.

"I felt like it's safer over here," she teased.

Song selection, however, proved riskier on Tuesday's episode. The judges were particularly turned off by the uninspired renditions of Fleetwood Mac's 'Landslide' from spunky 24-year-old event coordinator Lacey Brown, of Amarillo, Texas, and Leona Lewis' 'Happy' from intrepid 22-year-old college student Ashley Rodriguez from Chelsea, Massachusetts.

"I think you're going backward," Cowell informed Rodriguez.

The judges were split on several singers, including twangy 16-year-old high school student Haeley Vaughn from Fort Collins, Colorado. Randy Jackson praised the guitar-strumming Vaughn's "unpredictability" and DeGeneres told Vaughn "you just shine", but Cowell proclaimed that her version of The Beatles' 'I Want to Hold Your Hand' was "verging on terrible".

"You're very pure," DioGuardi soothed a smiling Vaughn.

The top 12 male semifinalists – including last-minute semifinalist replacement 20-year-old college student Tim Urban from Duncanville, Texas – took the stage for last night's episode. The two female contestants and two male contestants with the lowest viewer votes are slated to be eliminated live tonight.