Measuring Large Sound
In the summer of 2011, U2 played for a sold out crowd in Seattle during their long-awaited 360° Tour. CenturyLink field (formerly Qwest Field) is well known in sports circles for its amplification of crowd noise, and the band is known for their big anthems suited for large arenas, so the stage was set for a loud show.
SSA provided environmental noise monitoring and measurements for CenturyLink Field, at a major city stadium in Seattle used for NFL games, MLS games, and other large scale spectator events.
When hosting events, the Field must adhere to City of Seattle noise ordinances, or when necessary, apply for a noise variance. Major music concerts typically produce elevated noise measurements when music combines with crowd noise. The Field didn't have a representative measurement for noise for major music concerts. Without this measurement, they were unable to predict the noise impact of future music concerts and when a variance might be in order.
In order to establish a representative noise measurement for music concerts, noise levels were monitored from strategic positions inside and outside of the stadium during a sold out music concert. Noise measurements were taken by monitors set up in the north tower of the stadium, on a 60-feet high boom at a proposed property line of a future residential building, and on the rooftop of the nearest building.