Possible Clues:

• Following fire, save old instrument
• Bag this instrument, although one comes to blows with it
• Falstaff's sherry, with reservation, for old member of wind section
• That will put an end to 15 across, although it's just an old trombone
• Bag, only one blows into it
• In fire, save antique instrument
• Dismiss reported target of humour, old music-maker
• Trombone forerunner
• Dismiss objection from the old brass
• Wine barrel trimmed to make instrument