Berklee College of Music hosted a musical ribbon-cutting ceremony for its new tower on Massachusetts Avenue on Wednesday afternoon. Entertainment was provided by acts such as Berklee World Strings and the a cappella group Pitch Slapped. Speakers included the architect on the project, William Rawn. There was also an interactive light display that went with the music, courtesy of the Interdisciplinary Arts Ensemble, directed by Neil Leonard.Mark Shanahan can be reached at email@example.com. Follow him on Twitter @MarkAShanahan. Meredith Goldstein can be reached at firstname.lastname@example.org. Follow her on Twitter @MeredithGoldste.