[yummyfajitas]

There is at least one college which requires demonstrated skill (albeit not $N years of experience).

http://www.juilliard.edu/admissions/entrance/index.html

According to my mother (a musician) most music programs tend to require prior experience. The rationale is a stronger version of what forensic said: anyone serious about music would have already invested effort into learning how to play. The same could be easily said about CS.