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."
La Scala orchestra pit had not yet been built. Above the boxes, La Scala has a gallery—called the "loggione"—where the less wealthy can watch the performances. The gallery is typically crowded with the most critical opera aficionados, known as the loggionisti, who can be ecstatic or merciless towards singers' perceived successes or failures. For their failures, artists receive a "baptism of fire" from these aficionados, and fiascos are long remembered. For example, in 2006, tenor Roberto Alagna was booed off the stage during a performance of "Aida". This forced his understudy, Antonello Palombi, to quickly replace him mid-scene without time to change