"Gran Partita" translates to "Great Party" in English. However, it is also the title of a famous serenade composed by Wolfgang Amadeus Mozart, so it may refer specifically to that in a musical context.

Vienna in the 1780s: The city pulses 24/7 with music, concerts, fairs, operas, balls, and outdoor entertainments. Mozart is right in the middle of it all. Those who can afford it hire a live band for the evening festivities, known as "Harmoniemusik." This consists of a changing ensemble of wind instruments. Emperor Joseph II maintains his own Harmoniemusik at court. The nobility follows suit, and this trend trickles down through the social classes to the unemployed street musicians, who band together and offer their Harmoniemusik to passersby. And Mozart? He breaks the mold of the genre. The Serenade KV 361 lasts almost an hour and features seven movements that showcase not only compositional craftsmanship of the highest order but also an emotional rollercoaster like no other—beautiful enough to make one cry and funny enough to make one fall over, with everything in between. It’s no wonder that Peter Shaffer, in his play "Amadeus," chooses a passage from this work that leaves the competitor Antonio Salieri marveling at what he calls "the voice of God." Mozart composes for 13 instruments, including the then-new basset horns for the first time. He will use them again and again, even in his Requiem.