The Idol judge says the audition process has been "different" due to Paula Abdul's absence, Extrareported Friday.
"It's like comparing a carrot to a banana," Cowell told Extra correspondent Terri Seymour when asked to elaborate on how the Idol auditions are different without Abdul.
Idol has been using a series of guest judges during auditions to fill in for Abdul -- who announced she would not be returning as a judge for the show's ninth season last month. She reportedly rejected a $5 million a year offer to continue serving on the Fox mega-hit's judging panel.
While Cowell said he doesn't want to "get in the middle" of the problems Abdul is having with Idol's executives, he did have a moment of sincerity.
"I miss her, of course," Cowell told Extra.
While Idol will not begin its semifinal performance shows until late February, a series of guest judges have replaced Abdul at the ninth-season callback auditions.
Victoria Beckham (Denver and Boston), Mary J. Blige (Atlanta), Joe Jonas and Neil Patrick Harris (Dallas), Kristin Chenoweth (Orlando), and Shania Twain (Chicago) have served as guest judges at the ninth season's previous audition locations, with Katy Perry and Avril Lavigne scheduled to do the same at the final auditions in Los Angeles over the weekend.