In 1994, singer-songwriter Jeff Tweedy formed Wilco with three of his band mates following the break-up o  alt-country pioneers Uncle Tupelo. A.M., Wilco's debut, represents his first step into increasingly adventurous territory.  Tweedy shows an undeniable feel for melody, a gift for the resonant rhyme and an unhurried voice that reeks of cigarettes and charisma,  declared the Chicago Sun-Times.