Opera house electronic libretto systems have begun to be used in some opera houses, including New York's Metropolitan Opera, Milan's La Scala, and the Crosby Theatre of The Santa Fe Opera, which provide two lines of text on individual screens attached to the backs of the seats so as to not interfere with the visual aspects of the performance. A subtle type of sound reinforcement called acoustic enhancement is used in some opera houses. Acoustic enhancement systems help give a more even sound in the hall and prevent "dead spots" in the audience seating area by "...augment[ing] a hall's intrinsic acoustic characteristics."
Central City Opera House picture theatre. The Opera House closed in 1927. The opera house was donated to the University of Denver in May 1931 by MacFarlane's heirs and restoration was organized by the newly formed Central City Opera House Association. The summer of 1932, actress Lillian Gish opened the newly restored opera house with "Camille". It began a tradition of offering summer opera and theater festivals, which have become nationally recognized. The Central City Opera company was also formed that year. It is fifth the oldest opera company in the United States. One of its popular performances is "The Ballad of Baby Doe",