Greg Kot has been the Chicago Tribune's rock music critic since 1990. He co-hosts the nationally syndicated rock 'n' roll talk show Sound Opinions (soundopinions.org) on public radio and is the author of Wilco: Learning How to Die and Ripped: The Digital Music Revolution. Jim DeRogatis is the former pop music critic at the Chicago Sun-Times, co-host of Sound Opinions, and the author of several books about music and culture, including Velvet Underground (Voyageur Press) and Let It Blurt: The Life and Times of Lester Bangs. Jim DeRogatis is the pop music critic at the Chicago Sun-Times, co-host of Sound Opinions, and the author of several books about music and culture, including Velvet Underground (Voyageur Press) and Let It Blurt: The Life and Times of Lester Bangs .