Possible Clues:

• Musical piece unknown in 60% of orchestras, oddly
• By the sound of it, for woman - Oh, that's it
• Players' lively passage
• Abandoned chores to digest Berlioz's last composition
• After contralto's beginning, the woman's variable in extremely lively movement
• Thus losing heart, leading man embraces unknown movement
• Fast movement, musically
• Vigorous (musical) movement
• Horse caught prancing with Zulu -- that's lively!
• Half the school get zero, unusual for music