The track everyone knows is already playing. Then a saxophone cuts across it from somewhere in the crowd, and the whole floor goes up.
A sax player layered over a DJ set is one of the most reliable lifts you can give an evening. Live improvisation over the tracks your guests already love, played roaming through the dance floor rather than from a stage, so the energy moves with them. Earlier in the day the same performer works completely differently, playing smooth and low through a drinks reception or under a meal.
Bring one in for the ceremony, the reception and the evening and you have live music running through the entire day, from one booking.