The House of Music, or Haus der Musik, rates among the best museums in the city. Spread over 4 floors (the 5th is a café and restaurant), it helps explain sound in an amusing and interactive way, accessible to both children and adults.
The 1st floor houses the Vienna Philharmonic's historical archives, where a shortened version of the world famous New Year's concert can be heard and you can compose your own waltz with the interactive roll of a die. The 2nd floor's "prenatal listening room" re-creates noises heard by babies in the womb. Haydn, Mozart, Beethoven, Schubert, Strauss and Mahler each have a room on one level and yet another floor deals with experimental and electronic music. Displays are very interactive.
Tram 1 & 2 will take you there, as will bus 3A.