Related Clues:
- Alternative to quadraphonic
- Thing with tracks for runners
- Music storage medium
- Auto installation
- Dashboard installation
- Player in a pocket
- Apple for a music teacher?
- Item clipped on a waistband, perhaps
- Most music is played in it
- New player of 2001
- Sound way to hear music
- Hi-fi setup
- Music lover's carry-along
- Many a museum audio guide
- Popular Apple, versions of which begin 17-, 25-, 41- and 54-Across