Steven Tyler back on 'Idol'.

STEVEN TYLER: Here Comes the Judge Again

Steven Tyler is back for his second season as a judge on American Idol starting tonight. When asked if he will take a tougher stance on judging contestants this year, he said, "I'm not so sure if harder is what should be done... You know, how far do you go with it?"

Tyler has already been months into season two as he and his fellow judges --Jennifer Lopez and Randy Jackson -- have auditioned wannabe stars in Savannah, Georgia; Aspen, Colorado; Galveston, Texas; Pittsburgh, Portland, Oregon; San Diego and St. Louis. American Idol premieres with a two-hour episode on FOX at 8 followed by a one-hour show tomorrow at 8.

Tyler, along with Jackson and Aerosmith guitarist Joe Perry will perform on NBC's Tonight Show Friday.