Conant most recently played with the Lyric Opera Orchestra during the 'Stars of Lyric Opera at Millennium Park' free concert on September 10. The performance included his viola solo during The Tales of Hoffman, and was heard by more than 15,000 people in the park.
"I am shocked and deeply saddened by the news of Keith's death," said Sir Andrew Davis, Lyric's music director. "He was a wonderful musician and colleague whose kind and gentle spirit shone through in the musical gift he shared with us all."
Conant had been the principal violist since the 1997-98 season. He joined the orchestra for the 1987-88 season.
"From both an artistic and a human point of view it is a great loss," said Bruno Bartoletti, Lyric's artistic director emeritus, who hired Mr. Conant in 1987. "He was a splendid first viola and we will miss him a great deal."
Conant also held positions during his career with the Chicago Philharmonic, American Philharmonic Orchestra, the New York Youth Symphony, the Tanglewood Young Artists Orchestra, and the Seattle Symphony Orchestra. He was a founding member of the Rembrandt Chamber Players and performed with the ensemble for 18 of its 22 years. The ensemble is dedicating its 2011-12 season to his memory
"I can't think of another person who cared more for those around him and took the time to listen and support their needs if he could in any way," said violist Patrick Brennan, a longtime member of the Lyric Opera Orchestra. "We truly lost a good friend and brother."
Conant taught viola privately and served as an adjunct professor at Valparaiso University. He was born in Rockville Centre, New York, and grew up in Westport, Connecticut. He studied viola at the Juilliard School of Music with Paul Doktor, graduating in 1986.
Conant is survived by his partner Daniel Goss; by his sister Katherine O'Shea (Don O'Shea) of California, his brothers Scott Conant (Joanne Conant) and Jim Conant, both of Connecticut, and seven nieces and nephews.
Visitation for Conant will be 2 - 8 p.m. on Thurs., Sept. 22, Olson-Burke-Sullivan Funeral Home, 6467 N. Northwest Highway, Chicago.