The Pacific Amphitheatre opened in 1983 in the heart of Costa Mesa, on the grounds of the Orange County Fair and Event Center. Its arc shape was built to seat 18,765 people, with about 10,000 of them on the surrounding lawn.
Many prominent acts performed at the Pacific, including Madonna, Billy Idol, Bob Dylan, and even the reunion tour of The Rat Pack with Frank Sinatra, Sammy Davis Jr., and Dean Martin. In spite of the high profile acts, the Amphitheatre had never turned a profit since its opening due to a long and bitterly contested lawsuit by nearby residents over loud noise from rock concerts.
MLA worked with the Amphitheatre as an expert on the noise litigation during the early 1990s. Part of the work included the design of a sound system, which was used for one season of concerts. This design included detailed modeling of loudspeaker coverage and barrier shielding for the neighbors. Based on the modeling, levels were established for compliance with the city noise ordinance.