A band is playing at the Falls Festival. The stage is 1.5m offthe ground and there is a flat wall behind them. The sound radiatesout from the band, acting like a spherical sound source, and theaudience does not reflect any of the sound. If the sound pressurelevels 45m from the band are measured at 120dBA, how far from theband do you need to be standing to have the sound loudness double?*Please note: The Directivity Index for a flat wall at the centerof a surface can be approximated as 3
