UMich minimum requirements for SMTD can be found at http://www.music.umich.edu/prospective_students/admissions/ug/app_proc/acad_prep.htm
These requirements (3.0 GPA, 24 ACT, etc.) are set by SMTD and may be different for other schools, like engineering. The same page gives the average stats for the SMTD incoming 2014 students as 3.6 GPA and 28 ACT. These SMTD average stats are lower than the average stats for all UMich freshmen.