Possible Clues:

• Improvised performance is fast, with sound turned up about start of show
• Musical get-together
• Jerusalem supports king hosting small gathering of musicians
• Preserve hearing in jazz performance
• Crowd sitting for improvised performance
• Professional development for a Smucker's employee?
• Musical soirée? WI enjoy this when they're not singing?
• *Musicians’ improvisational get-together
• Join masses dancing for music performance
• Improvisational playing