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."
Lohengrin (opera) of the vocal score with his impressions and opinions of Wagner (this was almost certainly his first exposure to Wagner's music). La Scala produced the opera for the first time on 30 March 1873, with Campanini as Lohengrin, Gabrielle Krauss as Elsa, Philippine von Edelsberg as Ortrud, Victor Maurel as Friedrich, and Gian Pietro Milesi as Heinrich. The United Kingdom premiere of "Lohengrin" took place at the Royal Opera House, Covent Garden, on 8 May 1875 using the Italian translation by Marchesi. Auguste Vianesi conducted the performance, which featured Ernesto Nicolini as Lohengrin, Emma Albani as Elsa, Anna D'Angeri as