How do you guide museum visitors through the unseen world of sound? That was the dilemma faced by the designers and builders of the new $125-million Musical Instrument Museum in Phoenix, scheduled to open this spring.

Featuring both historic and contemporary instruments from around the globe, the museum aims to help visitors better understand musical expression in different cultures and in various aspects of life. Bob Ulrich, former CEO of the Target Corp., is the museum’s founder and chairman; the international retailer also contributed money and services to the project.