Related Clues:

• Record player produces two notes, drowned by a third
• One's out of place on old hi-fi
• Matched, rivalled
• Hi-fi (system)
• Good quality sound
• In two-channel sound
• Good quality sound system
• Twin-channel sound
• If I follow Planck's constant, it should make all the right noises?
• Where to put a rock collection?
• CD-player ancestor
• Like most new TV's
• Stereo system of yore
• Prefix meaning 'having three dimensions'
• See 1 Down