Chicago XI  by Chicago

Chicago XI is the ninth studio album by the American band Chicago, which was released on September 12, 1977, by Columbia Records. This album is considered historic as it marks the end of an era since it was the last work with the original guitarist and singer Terry Kath before his death, as well as the last collaboration with producer James William Guercio.

The musical style of Chicago XI is characterized as an eclectic mix that reflects the band's transition from the experimental jazz-rock of the early years to a more commercial pop orientation. The album was recorded between April and June of 1977 at Guercio's proprietary studio, Caribou Ranch in Colorado. Carl Wilson of the Beach Boys provided backing vocals on Baby, What A Big Surprise, the album's biggest hit, while Chaka Khan did the same at the end of Take Me Back To Chicago. The cover was designed by John Berg and depicts a topographic map of the greater Chicago area.

Chicago XI reached No. 6 in the U.S. It was the band's last album to enter the Top-10 until Chicago 16 in 1982. It went platinum in the U.S. - selling over 1,000,000 copies - in October 1977, and also achieved significant sales in Canada.