Related Clues:

• Musical note
• Muscular condition
• Tuning fork's output
• Instrument quality
• Coloration
• Concern of a musician or bodybuilder
• Tenor
• Literary style
• Sci-fi, for one
• What calisthenics improve
• Distinctive quality
• Strengthen, with 'up'
• Voice nuance
• Quality of voice
• Pre-dial sound