Teaching advanced undergraduate students principles of outdoor sound propagation using football game measurements

As part of a sound system evaluation at Brigham Young University’s football stadium and to assist in planning for future system design, measurements were made before and during games by an upper-level undergraduate acoustics class. The measurement experience provided significant training opportunities for the students. Teams of students used sound level meters to make recordings at numerous locations both inside and outside the stadium. These measurements were then correlated with data from stationary microphones placed near the field. From the data, the predicted slow, A-weighted equivalent levels in and around the stadium were calculated relative to an assumed 90 dBA on the sideline. Straightforward outdoor sound propagation prediction methods involving geometric spreading, atmospheric absorption, barriers, etc. were successfully used to validate the measured data within 1-2 decibels at many locations, including a location in the foothills to the southeast of the stadium at a distance of approximately 3 km. The students appreciated the hands-on experiences gained by participation in the measurements and analysis.