This is the best museum in Arizona, and may be one of the best in the United States. Seriously, this beautifully done museum houses an extensive collection of musical instruments from around the world and across all time. It is nestled in the North Phoenix desert far away from most resorts, but close to the freeways for quick access. The building and landscaping is enough for a visit, but then the music starts.
For a steep admission price, you get access to the expansive exhibits and an audio guide that really opens up the experience. The guide plays the audio of the various video screens in each exhibit. This allows you to hear the instruments being played and really enriches your experience. It is like a long concert walking around the museum, hearing many different expressions of the musical world.
Younger kids will probably get bored easily, unless there are some special kids activities in the museum. The museum is large enough that older kids can have some roaming time without much worry. The onsite cafe is nice too.
This place can easily take most of your day, but your feet will probably give out before your ears. It is a perfect place to escape the summer heat, and the interactive exhibit will allow you to finally act on your urge to touch everything by the end. This place is just amazing, and vacations should be built around it.