English oversaw a tumultuous period at the BSO. Last year, the orchestra named Marin Alsop as music director, despite musicians' public objections to the appointment. In January, James Glicker, the orchestra's CEO since mid 2004, stepped down. And earlier this spring, after posting a series of deficits, the orchestra cashed in part of its endowment.
In a letter to the BSO board, English said that he was leaving in order to devote more of his time to his venture capital business, Broventure. He said that he would remain involved with the orchestra.
Vice president and general manager Karen Swanson also announced that she would step down, according to the Sun. Officials said the two resignations were not related to each other.