In the late 1960s, Janis Joplin went on tour with a novel opening act that caused just as much buzz as her own show.
It was a rock band with a horn section, and it called itself the Chicago Transit Authority. Later, when the real transit authority objected, the name was shortened to just Chicago.
"I remember being backstage with Janis, with her bottle of Hennessy (cognac)," said Chicago trombonist and arranger Jimmy Pankow.
"She befriended us. Janis was disenchanted with her own people on the tour because they were all yes-men," Pankow said. "She hung with us on the road, because we treated her like an equal."
Still on the road after more than four decades, and fresh from an appearance on the Grammy Awards telecast in January, Chicago plays Tuesday at Santa Rosa's Wells Fargo Center for the Arts.
"This month, it's 47 years we've been doing this, and trying to get it right," Pankow said with a laugh, speaking by phone from his Nashville home.
With more than 100 million records sold, including 21 top-10 singles, Chicago clearly has done something right.
"When we were sitting at a keyboard writing these songs, and putting our personal angst on tape," Pankow said, the musicians didn't know the songs would be embraced by several generations to come.
Over time, Chicago's hits, including "If You Leave Me Now," "25 or 6 to 4" and "Does Anybody Really Know What Time It Is?," have become classics.
"We're dumbfounded at the fact that these songs, that started with these personal feelings, have become part of the fabric of so many lives," Pankow said.