1) Vocal duet 
A block party or street party is a crowded party in which many members of a single community congregate, either to observe an event of some importance or simply for mutual enjoyment. The name comes from the form of the party, which often involves closing an entire city block to vehicle traffic. Many times, there will be a celebration in the form o...
a free party on the streets of a city block - Are you going to the block party on Saturday?
an outdoor festival, usually held in a closed-off city street, often to raise money for a local organization or for a block association.