The purpose of this study was to evaluate temporary changes in auditory function associated with marching band practice among college-aged marching band participants. Each eligible musician was tested before and after two practices in the time span of one week. Sound level recordings at a location close to the center of the marching band were documented to be 85 - 105 dB(A), with peaks measured at 114 dB(A). Pure-tone thresholds and transient evoked (TEOAE) and distortion product (DPOAE) otoacoustic emissions were tested to evaluate if any changes occurred as a result of the marching band practices. If clinically significant changes were noted from pre- to post-practice testing, the band member returned the following morning to evaluate if any recovery had occurred. The principal finding was a significant effect of test time (pre versus post-practice), which was observed in the pure-tone data (3000, 4000, 6000 and 8000 Hz), DPOAE data (3000 Hz, left ear only) and TEOAE data (narrowband and broadband) in the marching band group. For those participants who showed clinically significant changes in auditory function, these changes were found to recover by the next morning. The results suggest that the measured changes in this study are temporary in nature; however, they might be an early indication of future permanent changes. Comparison of data from the marching band members and the control group participants revealed a significant difference between the groups in two measures: pure-tone thresholds at 8000 Hz and TEOAEs (broadband and narrowband). Overall, participation in the two-hour, outdoor marching band practice was not found to be more detrimental to auditory functioning than everyday noise exposure. However, there is evidence that exposure to marching band music produces subtle changes in auditory functioning, particularly as measured with pure-tone thresholds and TEOAEs.