Related Clues:

• Single-speaker sound
• In single-channel sound
• Old hi-fi format
• Source of some fevers
• Record will be playing in little while
• The 'kissing disease,' casually
• The "kissing disease," casually
• Less than stereo
• One quarter of tetra-
• Having only one channel
• Pre-stereo format
• Like early vinyl records
• Like 1950s LPs
• Like pre-stereo sound
• Precursor of 12-Across