Kara DioGuardi says Ellen DeGeneres brings a sense of humor to American Idol this season. “I think she also knows more about music than you think she does,” the second-year judge said to a conference call of reporters Wednesday. “I felt she had a really good handle on whether a contestant had potential, had star quality. She knew if something was off in the vocals or in their performance. And I thought she delivered the message with kindness but also had criticism in there .”

Kara declined to compare Ellen with her predecessor, Paula Abdul. “They’re completely different,” she said, “and they both bring something really valuable to the table.” She did, however, think that Andrew Garcia’s re-interpretation of Paula’s hit Straight Up was “genius.”

As a rule, Kara opted not to comment on specific contestants that weren’t shown during last night’s first Hollywood show. She did say, however, that she was disappointed by one male contestant, who showed more of a country orientation during his audition then decided to go a completely different direction in Hollywood. (She didn’t name the singer or say how far he progressed in Hollywood.)

She was also pleased to hear two of her songs sung last night — Didi Benami’s Terrified and Mary Powers’ Sober. “I was absolutely shocked,” she said of Didi’s rendition. “She showed that she had a great range and a sensitivity when she sings. I was pretty impressed by her.”

One difference she notices this year, perhaps a response to Adam Lambert and Kris Allen’s performances last season: “People were interpreting songs from the get-go, in audition week. … They were taking some risks, and I like that.”

Asked about rumors of tension on the set between Ellen DeGeneres and Simon Cowell, kara said: “You need to take any rumor you hear about American Idol with a rain of salt. They’re usually not true.”

Kara also addressed the Howard Stern buzz, and she didn’t seem favorably inclined to the possibility of having him as a judge. “I don’t think he has a musical background,” she said. “If you’re going to replace Simon, you have to have that background. You have to be somebody who knows about signing great artists and being a part of their career from the very beginning to the very end, like he’s done with people like Leona Lewis.”

Kara said she’d love to see Harry Connick Jr. as a mentor for the show at some point. “I think he’d be great, especially for standards, maybe even jazz,” she said. She especially likes the way Meat Loaf brings a method-acting approach to performing. “I think he’d be fun for rock.”

She’d also love to see a girl win: “”They’re unique, they different, they have a voice. But I also think the men are very good.”